wip

* Fixed typo in message

* Fixed typo in message

.gitignore

@@ -1,7 +1,7 @@
 .idea/*
 .idea/codeStyleSettings.xml
 .temp/*
-composer.lock
+/composer.lock
 /vendor/
 coverage.xml
 .phpunit.result.cache

CLAUDE.md

@@ -0,0 +1,34 @@
+# CLAUDE.md
+
+**Do not edit this file.** Agents must never add, remove, or reword anything here. If a change seems needed, say so and let a human do it.
+
+## Ask before testing
+
+When asked to review code or build a feature, do not run the test suite and do not write new tests. Make the change, report it, then ask the user whether tests should be added — describing the tests you have in mind — and wait for the user to confirm.
+
+Two reasons this matters here: the suite takes minutes, and `tests/.snapshots/success.txt` plus the tally in `tests/Visual/Parallel.php` encode the whole suite's result, so a single added test breaks both.
+
+Once the user confirms:
+
+```bash
+composer test:unit         # fast, excludes the visual group
+composer test:integration  # visual and snapshot tests
+composer test              # everything CI runs, in CI's order
+composer update:snapshots  # only when a test was added or removed
+```
+
+## TIA scenario tests
+
+`tests/Features/Tia/*` scaffold a throwaway git project, run a real `pest` subprocess against it, and diff the TIA graph it wrote. They exist because TIA's contract is about what a run *writes* — replay, branch keys, and the COMPLETE / RESULTS-ONLY / HARD-SUPPRESSED tiers are invisible to ordinary assertions, and every case used to be measured by hand against a playground app.
+
+Add one whenever a change touches branch resolution, replay, filtered mode, or the write tiers. How:
+
+- `Project::make('master')` scaffolds; `seed('master')` writes a graph and sentinels every cached result (`time=9.999`, `assertions=42`) so any rewrite shows up.
+- `$project->pest('--tia', …)` runs it; `$project->delta()` compares against that snapshot. `writtenCount()` is the discriminator — `0` means "replayed", not "wrote the same values". `mutateGraph()` bends one entry; overlays in `tests/Fixtures/Tia/overlays/<name>/` supply a different `tests/Pest.php`.
+- Keep expectations driver-independent: a cold recording run needs pcov/xdebug and behaves differently without one. Seed a graph instead of recording one.
+
+Run them by file (a directory argument finds nothing) or by `--filter`:
+
+```bash
+php bin/pest tests/Features/Tia/PartialRunWriteTier.php
+```

README.md

@@ -12,7 +12,7 @@
 
 ------
 
-> Pest v5 Now Available: **[Read the announcement »](https://pestphp.com/docs/pest-v5-is-here)**.
+> Pest v5 Now Available: **[Read the announcement »](https://pestphp.com/docs/pest5-now-available)**.
 
 **Pest** is an elegant testing framework for PHP developers and AI agents.
 
@@ -35,6 +35,7 @@ We cannot thank our sponsors enough for their incredible support in funding Pest
 - **[SerpApi](https://serpapi.com/?ref=nunomaduro)**
 - **[Typesense](https://typesense.org/?ref=nunomaduro)**
 - **[Bento](https://bentonow.com/?ref=nunomaduro)**
-- **[Redberry](https://redberry.international/laravel-development/)**
+- **[Pixel](https://wearepixel.com.au/?ref=nunomaduro)**
+- **[Redberry](https://redberry.international/laravel-development/?ref=nunomaduro)**
 
 Pest is an open-sourced software licensed under the **[MIT license](https://opensource.org/licenses/MIT)**.

composer.json

@@ -18,19 +18,19 @@
     ],
     "require": {
         "php": "^8.4",
-        "brianium/paratest": "^7.23.0",
+        "brianium/paratest": "^7.23.1",
         "nunomaduro/collision": "^8.9.5",
         "nunomaduro/termwind": "^2.4.0",
         "pestphp/pest-plugin": "^5.0.0",
         "pestphp/pest-plugin-arch": "^5.0.0",
-        "pestphp/pest-plugin-mutate": "^5.0.0",
+        "pestphp/pest-plugin-mutate": "^5.0.1",
         "pestphp/pest-plugin-profanity": "^5.0.0",
-        "phpunit/phpunit": "^13.2.4",
+        "phpunit/phpunit": "^13.2.6",
         "symfony/process": "^8.1.0"
     },
     "conflict": {
         "filp/whoops": "<2.18.3",
-        "phpunit/phpunit": ">13.2.4",
+        "phpunit/phpunit": ">13.2.6",
         "sebastian/exporter": "<7.0.0",
         "webmozart/assert": "<1.11.0"
     },
@@ -48,6 +48,7 @@
             "Tests\\Fixtures\\Covers\\": "tests/Fixtures/Covers",
             "Tests\\Fixtures\\Inheritance\\": "tests/Fixtures/Inheritance",
             "Tests\\Fixtures\\Arch\\": "tests/Fixtures/Arch",
+            "Tests\\Fixtures\\Tia\\": "tests/Fixtures/Tia",
             "Tests\\": "tests/PHPUnit/"
         },
         "classmap": [
@@ -58,12 +59,11 @@
         ]
     },
     "require-dev": {
-        "laravel/pao": "^1.1.2",
         "pestphp/pest-dev-tools": "^5.0.0",
         "pestphp/pest-plugin-browser": "^5.0.0",
         "pestphp/pest-plugin-phpstan": "^5.0.0",
-        "pestphp/pest-plugin-rector": "^5.0.0",
+        "pestphp/pest-plugin-rector": "^5.0.2",
-        "pestphp/pest-plugin-type-coverage": "^5.0.0",
+        "pestphp/pest-plugin-type-coverage": "^5.0.2",
         "psy/psysh": "^0.12.24"
     },
     "minimum-stability": "dev",
@@ -94,6 +94,7 @@
         "test:inline": "php bin/pest --configuration=phpunit.inline.xml",
         "test:parallel": "php bin/pest --exclude-group=integration --parallel --processes=3",
         "test:integration": "php bin/pest --group=integration -v",
+        "test:tia": "php bin/pest --group=tia -v",
         "update:snapshots": "REBUILD_SNAPSHOTS=true php bin/pest --update-snapshots",
         "test": [
             "@test:lint",

overrides/Runner/TestSuiteLoader.php

@@ -90,11 +90,11 @@ final class TestSuiteLoader
         (static function () use ($suiteClassFile) {
             try {
                 include_once $suiteClassFile;
+
+                TestSuite::getInstance()->tests->makeIfNeeded($suiteClassFile);
             } catch (Throwable $e) {
                 Panic::with($e);
             }
-
-            TestSuite::getInstance()->tests->makeIfNeeded($suiteClassFile);
         })();
 
         $loadedClasses = array_values(

phpunit.xml

@@ -18,8 +18,9 @@
       <directory suffix=".php">./tests</directory>
       <directory suffix=".php">./tests-external</directory>
       <exclude>./tests/.snapshots</exclude>
-      <exclude>./tests/.tests</exclude>
       <exclude>./tests/Fixtures/Inheritance</exclude>
+      <exclude>./tests/Fixtures/Suites</exclude>
+      <exclude>./tests/Fixtures/Tia</exclude>
     </testsuite>
   </testsuites>
   <source>

pint.json

@@ -0,0 +1,5 @@
+{
+    "exclude": [
+        "tests/Fixtures/Suites"
+    ]
+}

rector.php

@@ -28,6 +28,7 @@ return RectorConfig::configure()
     ->withSkip([
         __DIR__.'/src/Plugins/Parallel/Paratest/WrapperRunner.php',
         __DIR__.'/tests/Fixtures/Arch',
+        __DIR__.'/tests/Fixtures/Suites',
         ReturnNeverTypeRector::class,
         ArrowFunctionDelegatingCallToFirstClassCallableRector::class,
         NarrowObjectReturnTypeRector::class,

resources/boost/skills/pest-testing/SKILL.blade.php

@@ -0,0 +1,196 @@
+---
+name: pest-testing
+description: "Use this skill for Pest PHP testing in Laravel projects only. Trigger whenever any test is being written, edited, fixed, or refactored — including fixing tests that broke after a code change, adding assertions, converting PHPUnit to Pest, adding datasets, and TDD workflows. Always activate when the user asks how to write something in Pest, mentions test files or directories (tests/Feature, tests/Unit, tests/Browser), or needs browser testing, smoke testing multiple pages for JS errors, architecture tests, or faster test runs with Test Impact Analysis. Covers: test()/it()/expect() syntax, datasets, mocking, browser testing (visit/click/fill), smoke testing, arch(), Livewire component tests, RefreshDatabase, Tia (--tia), sharding, and all Pest 5 features. Do not use for factories, seeders, migrations, controllers, models, or non-test PHP code."
+license: MIT
+metadata:
+  author: laravel
+---
+@php
+/** @var \Laravel\Boost\Install\GuidelineAssist $assist */
+@endphp
+# Pest Testing 5
+
+## Documentation
+
+Use `search-docs` for detailed Pest 5 patterns and documentation.
+
+## Basic Usage
+
+### Creating Tests
+
+All tests must be written using Pest. Use `{{ $assist->artisanCommand('make:test --pest {name}') }}`.
+
+The `{name}` argument should include only the path and test name, but should not include the test suite.
+- Incorrect: `{{ $assist->artisanCommand('make:test --pest Feature/SomeFeatureTest') }}` will generate `tests/Feature/Feature/SomeFeatureTest.php`
+- Correct: `{{ $assist->artisanCommand('make:test --pest SomeControllerTest') }}` will generate `tests/Feature/SomeControllerTest.php`
+- Incorrect: `{{ $assist->artisanCommand('make:test --pest --unit Unit/SomeServiceTest') }}` will generate `tests/Unit/Unit/SomeServiceTest.php`
+- Correct: `{{ $assist->artisanCommand('make:test --pest --unit SomeServiceTest') }}` will generate `tests/Unit/SomeServiceTest.php`
+
+### Test Organization
+
+- Unit/Feature tests: `tests/Feature` and `tests/Unit` directories.
+- Browser tests: `tests/Browser/` directory.
+- Do NOT remove tests without approval - these are core application code.
+
+### Basic Test Structure
+
+Pest supports both `test()` and `it()` functions. Before writing new tests, check existing test files in the same directory to match the project's convention. Use `test()` if existing tests use `test()`, or `it()` if they use `it()`.
+
+@boostsnippet("Basic Pest Test Example", "php")
+it('is true', function () {
+    expect(true)->toBeTrue();
+});
+@endboostsnippet
+
+### Running Tests
+
+- Run minimal tests with filter before finalizing: `{{ $assist->artisanCommand('test --compact --filter=testName') }}`.
+- Run all tests: `{{ $assist->artisanCommand('test --compact') }}`.
+- Run file: `{{ $assist->artisanCommand('test --compact tests/Feature/ExampleTest.php') }}`.
+- Run only tests affected by recent changes (Tia): `./vendor/bin/pest --parallel --tia`.
+
+## Assertions
+
+Use specific assertions (`assertSuccessful()`, `assertNotFound()`) instead of `assertStatus()`:
+
+@boostsnippet("Pest Response Assertion", "php")
+it('returns all', function () {
+    $this->postJson('/api/docs', [])->assertSuccessful();
+});
+@endboostsnippet
+
+| Use | Instead of |
+|-----|------------|
+| `assertSuccessful()` | `assertStatus(200)` |
+| `assertNotFound()` | `assertStatus(404)` |
+| `assertForbidden()` | `assertStatus(403)` |
+
+## Mocking
+
+Import mock function before use: `use function Pest\Laravel\mock;`
+
+## Datasets
+
+Use datasets for repetitive tests (validation rules, etc.):
+
+@boostsnippet("Pest Dataset Example", "php")
+it('has emails', function (string $email) {
+    expect($email)->not->toBeEmpty();
+})->with([
+    'james' => 'james@laravel.com',
+    'taylor' => 'taylor@laravel.com',
+]);
+@endboostsnippet
+
+## Pest 5 Features
+
+| Feature | Purpose |
+|---------|---------|
+| Tia (Test Impact Analysis) | Rerun only tests affected by recent changes |
+| Time-Balanced Sharding | Split tests across CI shards by execution time |
+| New Validation Expectations | `toBeEmail()`, `toBeUlid()`, `toBeIpAddress()`, and more |
+| Browser Testing | Full integration tests in real browsers |
+| Smoke Testing | Validate multiple pages quickly |
+| Visual Regression | Compare screenshots for visual changes |
+| Architecture Testing | Enforce code conventions |
+
+### Tia (Test Impact Analysis)
+
+Tia reruns only tests affected by recent changes and replays cached results for the rest, dramatically reducing suite duration:
+
+@boostsnippet("Tia Example", "shell")
+./vendor/bin/pest --parallel --tia
+@endboostsnippet
+
+- Replayed tests are not skipped — cached tests store everything they produced, including covered lines and branches.
+- Detects Laravel, Symfony, Livewire, and Inertia automatically.
+
+### New Validation Expectations
+
+Pest 5 ships eight new validation matchers, all supporting `.not` negation:
+
+@boostsnippet("Pest 5 Validation Expectations", "php")
+expect('nuno@pestphp.com')->toBeEmail();
+expect('01ARZ3NDEKTSV4RRFFQ69G5FAV')->toBeUlid();
+expect('192.168.1.1')->toBeIpAddress();
+expect('00:1a:2b:3c:4d:5e')->toBeMacAddress();
+expect('example.com')->toBeHostname();
+expect('example.co.uk')->toBeDomain();
+expect('Zm9vYmFy')->toBeBase64();
+expect('deadbeef')->toBeHexadecimal();
+@endboostsnippet
+
+### Time-Balanced Sharding
+
+Distribute tests across CI shards by execution time rather than count:
+
+@boostsnippet("Pest Sharding Example", "shell")
+./vendor/bin/pest --update-shards
+./vendor/bin/pest --shard=1/4
+@endboostsnippet
+
+Commit `tests/.pest/shards.json` to the repository so CI shards stay consistent.
+
+### Browser Test Example
+
+Browser tests run in real browsers for full integration testing:
+
+- Browser tests live in `tests/Browser/`.
+- Use Laravel features like `Event::fake()`, `assertAuthenticated()`, and model factories.
+- Use `RefreshDatabase` for clean state per test.
+- Interact with page: click, type, scroll, select, submit, drag-and-drop, touch gestures.
+- Test on multiple browsers (Chrome, Firefox, Safari) if requested.
+- Test on different devices/viewports (iPhone 14 Pro, tablets) if requested.
+- Switch color schemes (light/dark mode) when appropriate.
+- Take screenshots or pause tests for debugging.
+
+@boostsnippet("Pest Browser Test Example", "php")
+it('may reset the password', function () {
+    Notification::fake();
+
+    $this->actingAs(User::factory()->create());
+
+    $page = visit('/sign-in');
+
+    $page->assertSee('Sign In')
+        ->assertNoJavaScriptErrors()
+        ->click('Forgot Password?')
+        ->fill('email', 'nuno@laravel.com')
+        ->click('Send Reset Link')
+        ->assertSee('We have emailed your password reset link!');
+
+    Notification::assertSent(ResetPassword::class);
+});
+@endboostsnippet
+
+### Smoke Testing
+
+Quickly validate multiple pages have no JavaScript errors:
+
+@boostsnippet("Pest Smoke Testing Example", "php")
+$pages = visit(['/', '/about', '/contact']);
+
+$pages->assertNoJavaScriptErrors()->assertNoConsoleLogs();
+@endboostsnippet
+
+### Visual Regression Testing
+
+Capture and compare screenshots to detect visual changes.
+
+### Architecture Testing
+
+@boostsnippet("Architecture Test Example", "php")
+arch('controllers')
+    ->expect('App\Http\Controllers')
+    ->toExtendNothing()
+    ->toHaveSuffix('Controller');
+@endboostsnippet
+
+## Common Pitfalls
+
+- Not importing `use function Pest\Laravel\mock;` before using mock
+- Using `assertStatus(200)` instead of `assertSuccessful()`
+- Forgetting datasets for repetitive validation tests
+- Deleting tests without approval
+- Forgetting `assertNoJavaScriptErrors()` in browser tests
+- Prefixing `Feature/` or `Unit/` in `{name}` when using `make:test`

src/Bootstrappers/BootSubscribers.php

@@ -35,6 +35,12 @@ final readonly class BootSubscribers implements Bootstrapper
         Subscribers\EnsureTiaResultIsRecordedOnSkipped::class,
         Subscribers\EnsureTiaResultIsRecordedOnIncomplete::class,
         Subscribers\EnsureTiaResultIsRecordedOnRisky::class,
+        Subscribers\EnsureTiaResultIsRecordedOnNoticeTriggered::class,
+        Subscribers\EnsureTiaResultIsRecordedOnPhpNoticeTriggered::class,
+        Subscribers\EnsureTiaResultIsRecordedOnDeprecationTriggered::class,
+        Subscribers\EnsureTiaResultIsRecordedOnPhpDeprecationTriggered::class,
+        Subscribers\EnsureTiaResultIsRecordedOnWarningTriggered::class,
+        Subscribers\EnsureTiaResultIsRecordedOnPhpWarningTriggered::class,
         Subscribers\EnsureTiaAssertionsAreRecordedOnFinished::class,
     ];
 

src/Concerns/Testable.php

@@ -280,12 +280,14 @@ trait Testable
 
         /** @var Tia $tia */
         $tia = Container::getInstance()->get(Tia::class);
-        $status = $tia->getStatus(self::$__filename, $this::class.'::'.$this->name());
+        $status = $tia->getStatus(self::$__filename, $this->valueObjectForEvents()->id());
         $replay = ReplayType::fromStatus($status);
 
         if ($replay !== ReplayType::None) {
             assert($status !== null);
 
+            $this->__replay = $replay;
+
             match ($replay) {
                 ReplayType::Pass, ReplayType::Risky => $this->__beginReplay($replay, $tia),
                 ReplayType::Skipped => $this->markTestSkipped($status->message()),
@@ -319,7 +321,7 @@ trait Testable
     private function __beginReplay(ReplayType $replay, Tia $tia): void
     {
         $this->__replay = $replay;
-        $this->__replayAssertions = $tia->getAssertionCount($this::class.'::'.$this->name());
+        $this->__replayAssertions = $tia->getAssertionCount($this->valueObjectForEvents()->id());
         $this->__ran = true;
     }
 

src/Exceptions/AfterAllAlreadyExist.php

@@ -19,6 +19,6 @@ final class AfterAllAlreadyExist extends InvalidArgumentException implements Exc
      */
     public function __construct(string $filename)
     {
-        parent::__construct(sprintf('The afterAll already exists in the filename `%s`.', $filename));
+        parent::__construct(sprintf('The afterAll already exists in the filename [%s].', $filename));
     }
 }

src/Exceptions/AfterAllWithinDescribe.php

@@ -19,6 +19,6 @@ final class AfterAllWithinDescribe extends InvalidArgumentException implements E
      */
     public function __construct(string $filename)
     {
-        parent::__construct(sprintf('The afterAll method can not be used within describe functions. Filename `%s`.', $filename));
+        parent::__construct(sprintf('The afterAll method can not be used within describe functions. Filename [%s].', $filename));
     }
 }

src/Exceptions/AfterBeforeTestFunction.php

@@ -19,6 +19,6 @@ final class AfterBeforeTestFunction extends InvalidArgumentException implements
      */
     public function __construct(string $filename)
     {
-        parent::__construct('After method cannot be used with before the [test|it] functions in the filename `['.$filename.']`.');
+        parent::__construct('After method cannot be used with before the [test|it] functions in the filename ['.$filename.'].');
     }
 }

src/Exceptions/BeforeAllAlreadyExist.php

@@ -19,6 +19,6 @@ final class BeforeAllAlreadyExist extends InvalidArgumentException implements Ex
      */
     public function __construct(string $filename)
     {
-        parent::__construct(sprintf('The beforeAll already exists in the filename `%s`.', $filename));
+        parent::__construct(sprintf('The beforeAll already exists in the filename [%s].', $filename));
     }
 }

src/Exceptions/BeforeAllWithinDescribe.php

@@ -19,6 +19,6 @@ final class BeforeAllWithinDescribe extends InvalidArgumentException implements
      */
     public function __construct(string $filename)
     {
-        parent::__construct(sprintf('The beforeAll method can not be used within describe functions. Filename `%s`.', $filename));
+        parent::__construct(sprintf('The beforeAll method can not be used within describe functions. Filename [%s].', $filename));
     }
 }

src/Exceptions/DatasetAlreadyExists.php

@@ -19,6 +19,6 @@ final class DatasetAlreadyExists extends InvalidArgumentException implements Exc
      */
     public function __construct(string $name, string $scope)
     {
-        parent::__construct(sprintf('A dataset with the name `%s` already exists in scope [%s].', $name, $scope));
+        parent::__construct(sprintf('A dataset with the name [%s] already exists in scope [%s].', $name, $scope));
     }
 }

src/Exceptions/DatasetDoesNotExist.php

@@ -19,6 +19,6 @@ final class DatasetDoesNotExist extends InvalidArgumentException implements Exce
      */
     public function __construct(string $name)
     {
-        parent::__construct(sprintf("A dataset with the name `%s` does not exist. You can create it using `dataset('%s', ['a', 'b']);`.", $name, $name));
+        parent::__construct(sprintf("A dataset with the name [%s] does not exist. You can create it using `dataset('%s', ['a', 'b']);`.", $name, $name));
     }
 }

src/Exceptions/FileOrFolderNotFound.php

@@ -19,6 +19,6 @@ final class FileOrFolderNotFound extends InvalidArgumentException implements Exc
      */
     public function __construct(string $filename)
     {
-        parent::__construct(sprintf('The file or folder with the name `%s` could not be found.', $filename));
+        parent::__construct(sprintf('The file or folder with the name [%s] could not be found.', $filename));
     }
 }

src/Exceptions/InvalidTestClassName.php

@@ -0,0 +1,41 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Pest\Exceptions;
+
+use InvalidArgumentException;
+use NunoMaduro\Collision\Contracts\RenderlessEditor;
+use NunoMaduro\Collision\Contracts\RenderlessTrace;
+use Symfony\Component\Console\Exception\ExceptionInterface;
+
+/**
+ * @internal
+ */
+final class InvalidTestClassName extends InvalidArgumentException implements ExceptionInterface, RenderlessEditor, RenderlessTrace
+{
+    /**
+     * Creates a new Exception instance for the given class name.
+     */
+    public static function fromClassName(string $filename, string $className): self
+    {
+        return new self(sprintf(
+            'The test file [%s] would create the class [%s], which is not a valid PHP class name. Please rename the test file.',
+            $filename,
+            $className,
+        ));
+    }
+
+    /**
+     * Creates a new Exception instance for the given namespace.
+     */
+    public static function fromNamespace(string $filename, string $namespace, string $part): self
+    {
+        return new self(sprintf(
+            'The test file [%s] would create the namespace [%s], which is not a valid PHP namespace, as [%s] may not be used as a namespace name. Please rename the folder in question.',
+            $filename,
+            $namespace,
+            $part,
+        ));
+    }
+}

src/Exceptions/MissingDependency.php

@@ -19,6 +19,6 @@ final class MissingDependency extends InvalidArgumentException implements Except
      */
     public function __construct(string $feature, string $dependency)
     {
-        parent::__construct(sprintf('The feature "%s" requires "%s".', $feature, $dependency));
+        parent::__construct(sprintf('The feature [%s] requires [%s].', $feature, $dependency));
     }
 }

src/Exceptions/TestAlreadyExist.php

@@ -19,6 +19,6 @@ final class TestAlreadyExist extends InvalidArgumentException implements Excepti
      */
     public function __construct(string $fileName, string $description)
     {
-        parent::__construct(sprintf('A test with the description `%s` already exists in the filename `%s`.', $description, $fileName));
+        parent::__construct(sprintf('A test with the description [%s] already exists in the filename [%s].', $description, $fileName));
     }
 }

src/Exceptions/TestCaseClassOrTraitNotFound.php

@@ -19,6 +19,6 @@ final class TestCaseClassOrTraitNotFound extends InvalidArgumentException implem
      */
     public function __construct(string $testCaseClass)
     {
-        parent::__construct(sprintf('The class `%s` was not found.', $testCaseClass));
+        parent::__construct(sprintf('The class [%s] was not found.', $testCaseClass));
     }
 }

src/Exceptions/TestDescriptionMissing.php

@@ -19,6 +19,6 @@ final class TestDescriptionMissing extends InvalidArgumentException implements E
      */
     public function __construct(string $fileName)
     {
-        parent::__construct(sprintf('Test description is missing in the filename `%s`.', $fileName));
+        parent::__construct(sprintf('Test description is missing in the filename [%s].', $fileName));
     }
 }

src/Exceptions/TiaRequiresCommit.php

@@ -0,0 +1,49 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Pest\Exceptions;
+
+use NunoMaduro\Collision\Contracts\RenderlessEditor;
+use NunoMaduro\Collision\Contracts\RenderlessTrace;
+use Pest\Contracts\Panicable;
+use RuntimeException;
+use Symfony\Component\Console\Exception\ExceptionInterface;
+use Symfony\Component\Console\Output\OutputInterface;
+
+/**
+ * @internal
+ */
+final class TiaRequiresCommit extends RuntimeException implements ExceptionInterface, Panicable, RenderlessEditor, RenderlessTrace
+{
+    public function __construct()
+    {
+        parent::__construct(
+            'Tia mode requires a repository with at least one commit, so the baseline it records can be anchored to a revision.',
+        );
+    }
+
+    public function render(OutputInterface $output): void
+    {
+        $output->writeln([
+            '',
+            '  <fg=white;options=bold;bg=red> ERROR </> Tia mode requires at least one commit.',
+            '',
+            '  A baseline is anchored to the revision it was recorded at, and this repository',
+            '  has none yet, so there is nothing to record against and nothing to compare a',
+            '  later run to.',
+            '',
+            '  Commit once, then run again:',
+            '',
+            '    <fg=yellow>git add . && git commit -m "Initial commit"</>',
+            '',
+            '  Runs without <fg=yellow>--tia</> are unaffected.',
+            '',
+        ]);
+    }
+
+    public function exitCode(): int
+    {
+        return 1;
+    }
+}

src/Exceptions/TiaRequiresDefaultBranch.php

@@ -0,0 +1,52 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Pest\Exceptions;
+
+use NunoMaduro\Collision\Contracts\RenderlessEditor;
+use NunoMaduro\Collision\Contracts\RenderlessTrace;
+use Pest\Contracts\Panicable;
+use RuntimeException;
+use Symfony\Component\Console\Exception\ExceptionInterface;
+use Symfony\Component\Console\Output\OutputInterface;
+
+/**
+ * @internal
+ */
+final class TiaRequiresDefaultBranch extends RuntimeException implements ExceptionInterface, Panicable, RenderlessEditor, RenderlessTrace
+{
+    public function __construct()
+    {
+        parent::__construct(
+            'Tia mode could not determine the default branch every other branch falls back to reading.',
+        );
+    }
+
+    public function render(OutputInterface $output): void
+    {
+        $output->writeln([
+            '',
+            '  <fg=white;options=bold;bg=red> ERROR </> Tia mode could not determine the default branch.',
+            '',
+            '  It is the branch whose baseline every other branch falls back to reading, and',
+            '  nothing in this checkout names it: the repository has a remote, but no',
+            '  <fg=yellow>origin/HEAD</>, and no CI provider stated it either. Guessing would re-run the',
+            '  whole suite on every new branch while reporting it as a cache hit.',
+            '',
+            '  Name the branch in <fg=yellow>tests/Pest.php</>:',
+            '',
+            '    <fg=yellow>pest()->tia()->defaultBranch(\'master\');</>',
+            '',
+            '  Or let git answer, once per clone:',
+            '',
+            '    <fg=yellow>git remote set-head origin --auto</>',
+            '',
+        ]);
+    }
+
+    public function exitCode(): int
+    {
+        return 1;
+    }
+}

src/Exceptions/TiaRequiresRemote.php

@@ -0,0 +1,47 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Pest\Exceptions;
+
+use NunoMaduro\Collision\Contracts\RenderlessEditor;
+use NunoMaduro\Collision\Contracts\RenderlessTrace;
+use Pest\Contracts\Panicable;
+use RuntimeException;
+use Symfony\Component\Console\Exception\ExceptionInterface;
+use Symfony\Component\Console\Output\OutputInterface;
+
+/**
+ * @internal
+ */
+final class TiaRequiresRemote extends RuntimeException implements ExceptionInterface, Panicable, RenderlessEditor, RenderlessTrace
+{
+    public function __construct()
+    {
+        parent::__construct(
+            'Tia mode requires a repository with a remote, so the default branch every other branch falls back to reading can be resolved.',
+        );
+    }
+
+    public function render(OutputInterface $output): void
+    {
+        $output->writeln([
+            '',
+            '  <fg=white;options=bold;bg=red> ERROR </> Tia mode requires a repository with a remote.',
+            '',
+            '  Without one there is no way to tell which branch is the default — the branch',
+            '  whose baseline every other branch falls back to reading — so the first run on',
+            '  each new branch would silently re-run the whole suite.',
+            '',
+            '  Add a remote, or name the branch yourself in <fg=yellow>tests/Pest.php</>:',
+            '',
+            '    <fg=yellow>pest()->tia()->defaultBranch(\'master\');</>',
+            '',
+        ]);
+    }
+
+    public function exitCode(): int
+    {
+        return 1;
+    }
+}

src/Factories/TestCaseFactory.php

@@ -9,6 +9,7 @@ use Pest\Concerns;
 use Pest\Contracts\HasPrintableTestCaseName;
 use Pest\Evaluators\Attributes;
 use Pest\Exceptions\DatasetMissing;
+use Pest\Exceptions\InvalidTestClassName;
 use Pest\Exceptions\ShouldNotHappen;
 use Pest\Exceptions\TestAlreadyExist;
 use Pest\Exceptions\TestClosureMustNotBeStatic;
@@ -138,6 +139,16 @@ final class TestCaseFactory
 
         if (trim($className) === '') {
             $className = 'InvalidTestName'.Str::random();
+        } elseif (! Str::isValidClassName($className)) {
+            throw InvalidTestClassName::fromClassName($this->filename, $className);
+        }
+
+        if ($this->namespace === null) {
+            foreach ($partsFQN as $partFQN) {
+                if (! Str::isValidIdentifier($partFQN)) {
+                    throw InvalidTestClassName::fromNamespace($this->filename, $namespace, $partFQN);
+                }
+            }
         }
 
         $this->attributes = [

src/Pest.php

@@ -6,7 +6,7 @@ namespace Pest;
 
 function version(): string
 {
-    return '5.0.0-beta.1';
+    return '5.0.3';
 }
 
 function testDirectory(string $file = ''): string

src/Plugins/Help.php

@@ -114,6 +114,41 @@ final readonly class Help implements HandlesArguments
             ],
         ];
 
+        $content['Tia'] = [
+            [
+                'arg' => '--tia',
+                'desc' => 'Re-run only the tests affected by your changes, replaying the rest from cache',
+            ],
+            [
+                'arg' => '--no-tia',
+                'desc' => 'Disable test impact analysis for this run',
+            ],
+            [
+                'arg' => '--tia --fresh',
+                'desc' => 'Discard the recorded dependency graph and record it again',
+            ],
+            [
+                'arg' => '--tia --filtered',
+                'desc' => 'Narrow the run to the affected test files only',
+            ],
+            [
+                'arg' => '--tia --locally',
+                'desc' => 'Enable test impact analysis on local machines only',
+            ],
+            [
+                'arg' => '--tia --baselined',
+                'desc' => 'Fetch the shared dependency graph recorded by the CI baseline',
+            ],
+            [
+                'arg' => '--tia --refetch',
+                'desc' => 'Force a fresh fetch of the shared dependency graph',
+            ],
+            [
+                'arg' => '--baseline',
+                'desc' => 'Output to standard output the test impact analysis storage directory',
+            ],
+        ];
+
         $content['Execution'] = [...[
             [
                 'arg' => '--parallel',

src/Plugins/Parallel/Paratest/WrapperRunner.php

@@ -14,6 +14,7 @@ use ParaTest\RunnerInterface;
 use ParaTest\WrapperRunner\MissingResultsException;
 use ParaTest\WrapperRunner\SuiteLoader;
 use ParaTest\WrapperRunner\WrapperWorker;
+use Pest\Plugins\Tia;
 use Pest\Result;
 use Pest\TestSuite;
 use PHPUnit\Event\Facade as EventFacade;
@@ -155,6 +156,7 @@ final class WrapperRunner implements RunnerInterface
 
         /** @var array<int, non-empty-string> $parameters */
         $parameters = $this->handleLaravelHerd($parameters);
+        $parameters = $this->handleTia($parameters);
 
         $parameters[] = $wrapper;
         $parameters[] = '--test-directory='.TestSuite::getInstance()->testPath;
@@ -202,6 +204,19 @@ final class WrapperRunner implements RunnerInterface
         return $parameters;
     }
 
+    /**
+     * @param  array<int, non-empty-string>  $parameters
+     * @return array<int, non-empty-string>
+     */
+    private function handleTia(array $parameters): array
+    {
+        if (! Tia::recordsEdgesInWorkers()) {
+            return $parameters;
+        }
+
+        return array_merge($parameters, ['-d', 'pcov.directory='.TestSuite::getInstance()->rootPath]);
+    }
+
     private function startWorkers(): void
     {
         for ($token = 1; $token <= $this->options->processes; $token++) {

src/Plugins/Tia.php

@@ -7,13 +7,20 @@ namespace Pest\Plugins;
 use NunoMaduro\Collision\Adapters\Phpunit\Printers\DefaultPrinter;
 use Pest\Contracts\Plugins\AddsOutput;
 use Pest\Contracts\Plugins\HandlesArguments;
+use Pest\Contracts\Plugins\HandlesOriginalArguments;
 use Pest\Contracts\Plugins\Terminable;
+use Pest\Exceptions\InvalidOption;
+use Pest\Exceptions\MissingDependency;
 use Pest\Exceptions\NoAffectedTestsFound;
+use Pest\Exceptions\TiaRequiresCommit;
+use Pest\Exceptions\TiaRequiresDefaultBranch;
+use Pest\Exceptions\TiaRequiresRemote;
 use Pest\Exceptions\TiaRequiresRepositoryRoot;
 use Pest\Panic;
 use Pest\Plugins\Concerns\HandleArguments;
 use Pest\Plugins\Tia\BaselineSync;
 use Pest\Plugins\Tia\ChangedFiles;
+use Pest\Plugins\Tia\CiDefaultBranch;
 use Pest\Plugins\Tia\Contracts\State;
 use Pest\Plugins\Tia\CoverageCollector;
 use Pest\Plugins\Tia\Fingerprint;
@@ -26,17 +33,18 @@ use Pest\Plugins\Tia\Storage;
 use Pest\Plugins\Tia\TableExtractor;
 use Pest\Plugins\Tia\WatchPatterns;
 use Pest\Support\Container;
+use Pest\Support\Git;
 use Pest\Support\View;
 use Pest\TestCaseFilters\TiaTestCaseFilter;
 use Pest\TestSuite;
 use PHPUnit\Framework\TestStatus\TestStatus;
+use PHPUnit\TestRunner\TestResult\Facade as TestResultFacade;
 use Symfony\Component\Console\Output\OutputInterface;
-use Symfony\Component\Process\Process;
 
 /**
  * @internal
  */
-final class Tia implements AddsOutput, HandlesArguments, Terminable
+final class Tia implements AddsOutput, HandlesArguments, HandlesOriginalArguments, Terminable
 {
     use HandleArguments;
 
@@ -56,6 +64,8 @@ final class Tia implements AddsOutput, HandlesArguments, Terminable
 
     private const string BASELINE_PATH_OPTION = '--baseline';
 
+    private const string ENV_MUTATION_TESTING = 'PEST_MUTATION_TESTING';
+
     private const string ENV_TIA = 'PEST_TIA';
 
     private const string ENV_FILTERED = 'PEST_TIA_FILTERED';
@@ -86,8 +96,14 @@ final class Tia implements AddsOutput, HandlesArguments, Terminable
 
     private const string FILTERED_GLOBAL = 'TIA_FILTERED';
 
+    private const string WORKER_RESULTS_GLOBAL = 'TIA_WORKER_RESULTS';
+
     private const string PIGGYBACK_COVERAGE_GLOBAL = 'TIA_PIGGYBACK_COVERAGE';
 
+    private const string FALLBACK_BRANCH_GLOBAL = 'TIA_FALLBACK_BRANCH';
+
+    private const string DEFAULT_BRANCH = 'main';
+
     /**
      * PHPUnit/Pest CLI flags whose subsequent argument is a value, not a path.
      *
@@ -101,12 +117,32 @@ final class Tia implements AddsOutput, HandlesArguments, Terminable
         '--include-path', '--whitelist',
         '--log-junit', '--log-teamcity', '--testdox-html', '--testdox-text',
         '--coverage-clover', '--coverage-cobertura', '--coverage-crap4j',
-        '--coverage-html', '--coverage-php', '--coverage-text', '--coverage-xml',
+        '--coverage-html', '--coverage-openclover', '--coverage-php',
+        '--coverage-text', '--coverage-xml',
         '--coverage-filter', '--path-coverage',
         '--repeat', '--retry-times', '--memory-limit', '--seed',
         '--compact', '--ci-build-id', '--min',
     ];
 
+    /** @var list<string> */
+    private const array COVERAGE_REPORT_FLAGS = [
+        '--coverage-clover', '--coverage-cobertura', '--coverage-crap4j',
+        '--coverage-html', '--coverage-openclover', '--coverage-php',
+        '--coverage-text', '--coverage-xml',
+    ];
+
+    /** @var list<string> */
+    private const array PARTIAL_SELECTION_FLAGS = [
+        '--filter', '--exclude-filter', '--group', '--exclude-group',
+        '--covers', '--uses', '--testsuite', '--exclude-testsuite', '--test-suffix',
+        '--dirty', '--todo', '--todos', '--flaky', '--notes',
+        '--assignee', '--issue', '--ticket', '--pr', '--pull-request',
+    ];
+
+    private const array UNSUPPORTED_OPTIONS = [
+        '--covers', '--uses', '--random-order-seed',
+    ];
+
     private bool $graphWritten = false;
 
     private bool $replayRan = false;
@@ -120,9 +156,21 @@ final class Tia implements AddsOutput, HandlesArguments, Terminable
     /** @var array<string, int> */
     private array $cachedAssertionsByTestId = [];
 
+    /** @var array<string, array{status: int, message: string}> */
+    private array $cachedStatusByTestId = [];
+
+    /** @var array<string, float> */
+    private array $cachedTimeByTestId = [];
+
     private ?Graph $replayGraph = null;
 
-    private string $branch = 'main';
+    private string $branch = self::DEFAULT_BRANCH;
+
+    private string $fallbackBranch = self::DEFAULT_BRANCH;
+
+    private bool $fallbackBranchResolved = false;
+
+    private bool $branchResolved = false;
 
     /** @var array<string, true> */
     private array $affectedFiles = [];
@@ -138,10 +186,23 @@ final class Tia implements AddsOutput, HandlesArguments, Terminable
 
     private bool $baselineFetchAttemptedForDrift = false;
 
-    private bool $freshRebuild = false;
-
     private bool $filteredMode = false;
 
+    private bool $writesSuppressed = false;
+
+    private bool $resultsOnlyWrites = false;
+
+    private bool $flushesWorkerResults = false;
+
+    private bool $unreadableGraphReported = false;
+
+    private bool $detachedHead = false;
+
+    private bool $graphUnreachable = false;
+
+    /** @var array<int, string> */
+    private array $originalArguments = [];
+
     private ?string $driftLabel = null;
 
     private ?string $driftDetails = null;
@@ -185,11 +246,54 @@ final class Tia implements AddsOutput, HandlesArguments, Terminable
             return null;
         }
 
-        return Graph::decode($json, $projectRoot);
+        $graph = Graph::decode($json, $projectRoot);
+
+        if (! $graph instanceof Graph) {
+            $this->discardUnreadableGraph();
+
+            return null;
+        }
+
+        $graph->setFallbackBranch($this->fallbackBranch);
+
+        return $graph;
+    }
+
+    private function discardUnreadableGraph(): void
+    {
+        if (Parallel::isWorker()) {
+            return;
+        }
+
+        if (! $this->deleteState(self::KEY_GRAPH)) {
+            return;
+        }
+
+        if ($this->unreadableGraphReported) {
+            return;
+        }
+
+        $this->unreadableGraphReported = true;
+
+        $this->output->writeln('');
+        $this->renderBadge('WARN', 'The dependency graph could not be read — it will be rebuilt.');
+    }
+
+    private function deleteState(string $key): bool
+    {
+        if ($this->detachedHead) {
+            return false;
+        }
+
+        return $this->state->delete($key);
     }
 
     private function saveGraph(Graph $graph): bool
     {
+        if ($this->detachedHead) {
+            return true;
+        }
+
         $json = $graph->encode();
 
         if ($json === null) {
@@ -227,6 +331,12 @@ final class Tia implements AddsOutput, HandlesArguments, Terminable
         return ! self::argumentPresent('--ci', $arguments);
     }
 
+    public static function recordsEdgesInWorkers(): bool
+    {
+        return (string) Parallel::getGlobal(self::RECORDING_GLOBAL) === '1'
+            && (string) Parallel::getGlobal(self::PIGGYBACK_COVERAGE_GLOBAL) !== '1';
+    }
+
     /**
      * @param  array<int, string>  $arguments
      */
@@ -303,8 +413,18 @@ final class Tia implements AddsOutput, HandlesArguments, Terminable
             }
 
             $this->replayedCount++;
+            $this->cachedStatusByTestId[$testId] = [
+                'status' => $result->asInt(),
+                'message' => $result->message(),
+            ];
             $assertions = $this->replayGraph->getAssertions($this->branch, $testId);
             $this->cachedAssertionsByTestId[$testId] = $assertions ?? 0;
+
+            $time = $this->replayGraph->getTime($this->branch, $testId);
+
+            if ($time !== null) {
+                $this->cachedTimeByTestId[$testId] = $time;
+            }
         } else {
             $this->executedCount++;
         }
@@ -317,6 +437,14 @@ final class Tia implements AddsOutput, HandlesArguments, Terminable
         return $this->cachedAssertionsByTestId[$testId] ?? 0;
     }
 
+    /**
+     * {@inheritDoc}
+     */
+    public function handleOriginalArguments(array $arguments): void
+    {
+        $this->originalArguments = $arguments;
+    }
+
     /**
      * {@inheritDoc}
      */
@@ -339,9 +467,20 @@ final class Tia implements AddsOutput, HandlesArguments, Terminable
         $cliEnabled = $this->hasArgument(self::OPTION, $arguments) || self::envFlagEnabled(self::ENV_TIA);
         $alwaysEnabled = $watchPatterns->isEnabled()
             && (! $watchPatterns->isLocally() || Environment::name() === Environment::LOCAL);
+        if (! $isWorker && ! $disabled && ($cliEnabled || $alwaysEnabled)) {
+            $this->guardUnsupportedOptions($arguments);
+        }
+
+        $hasExplicitPath = $this->hasExplicitPathArgument($arguments);
+        $partial = ! $isWorker && ($hasExplicitPath || $this->hasPartialSelection($arguments));
+        $disabled = $disabled || $partial;
+
+        if (getenv(self::ENV_MUTATION_TESTING) !== false) {
+            $this->writesSuppressed = true;
+        }
         $enabled = ! $disabled && ($cliEnabled || $alwaysEnabled);
         $this->filteredMode = ($this->hasArgument(self::FILTERED_OPTION, $arguments) || self::envFlagEnabled(self::ENV_FILTERED) || $watchPatterns->isFiltered())
-            && ! $this->hasExplicitPathArgument($arguments)
+            && ! $hasExplicitPath
             && ! $this->coverageReportActive();
         $freshRequested = $this->hasArgument(self::FRESH_OPTION, $arguments);
         $this->forceRefetch = $this->hasArgument(self::REFETCH_OPTION, $arguments);
@@ -355,17 +494,35 @@ final class Tia implements AddsOutput, HandlesArguments, Terminable
         $arguments = $this->popArgument(self::BASELINED_OPTION, $arguments);
 
         if ($disabled) {
+            $this->requestWorkerResults();
+
+            if ($partial) {
+                $this->resultsOnlyWrites = true;
+
+                if ($cliEnabled || $freshRequested || $this->forceRefetch || $this->filteredMode) {
+                    $this->output->writeln('');
+                    $this->renderChild('TIA does not apply to partial runs — running the selected tests directly.');
+                }
+            }
+
             $this->forceRefetch = false;
             $this->filteredMode = false;
-            $this->freshRebuild = false;
+
+            return $arguments;
+        }
+
+        if ($isWorker && (string) Parallel::getGlobal(self::WORKER_RESULTS_GLOBAL) === '1') {
+            $this->flushesWorkerResults = true;
+            $this->resultsOnlyWrites = true;
 
             return $arguments;
         }
 
         $forceRebuild = $freshRequested && ($enabled || $recordingGlobal || $replayingGlobal);
-        $this->freshRebuild = $forceRebuild;
 
         if (! $enabled && ! $this->forceRefetch && ! $recordingGlobal && ! $replayingGlobal) {
+            $this->requestWorkerResults();
+
             return $arguments;
         }
 
@@ -388,10 +545,17 @@ final class Tia implements AddsOutput, HandlesArguments, Terminable
             return;
         }
 
-        if (Parallel::isWorker() && ($this->replayGraph instanceof Graph || $this->recordingActive)) {
+        if (Parallel::isWorker() && ($this->replayGraph instanceof Graph || $this->recordingActive || $this->flushesWorkerResults)) {
             $this->flushWorkerReplay();
         }
 
+        if ($this->writesSuppressed || $this->resultsOnlyWrites || $this->hasUnfinishedTest()) {
+            $this->recorder->reset();
+            $this->coverageCollector->reset();
+
+            return;
+        }
+
         $recorder = $this->recorder;
 
         if (! $this->recordingActive && ! $recorder->isActive()) {
@@ -453,15 +617,11 @@ final class Tia implements AddsOutput, HandlesArguments, Terminable
             $this->branch,
             $changedFiles->snapshotTree($changedFiles->since($currentSha) ?? []),
         );
-        $graph->replaceEdges($perTest);
+        $graph->replaceEdges($perTest, keepExisting: $this->piggybackCoverage);
         $graph->replaceTestTables($perTestTables);
         $graph->replaceTestInertiaComponents($perTestInertia);
         $graph->replaceJsFileToComponents(JsModuleGraph::build($projectRoot));
 
-        if ($this->freshRebuild) {
-            $graph->pruneMissingTests();
-        }
-
         $this->seedResultsInto($graph);
 
         if (! $this->saveGraph($graph)) {
@@ -481,13 +641,27 @@ final class Tia implements AddsOutput, HandlesArguments, Terminable
             return $exitCode;
         }
 
+        if (Only::isEnabled() || $this->stoppedEarly() || $this->hasUnfinishedTest()) {
+            $this->resultsOnlyWrites = true;
+        }
+
         $this->reportMissingWorkerDrivers();
 
         if (Parallel::isEnabled()) {
             $this->mergeWorkerReplayPartials();
         }
 
-        if ($this->replayRan) {
+        if ($this->writesSuppressed) {
+            return $exitCode;
+        }
+
+        if ($this->resultsOnlyWrites) {
+            $this->snapshotTestResults(complete: false);
+
+            return $exitCode;
+        }
+
+        if ($this->replayRan || $this->graphUnreachable) {
             $this->bumpRecordedSha();
         }
 
@@ -547,15 +721,11 @@ final class Tia implements AddsOutput, HandlesArguments, Terminable
             return $exitCode;
         }
 
-        $graph->replaceEdges($finalised);
+        $graph->replaceEdges($finalised, keepExisting: $this->piggybackCoverage);
         $graph->replaceTestTables($finalisedTables);
         $graph->replaceTestInertiaComponents($finalisedInertia);
         $graph->replaceJsFileToComponents(JsModuleGraph::build($projectRoot));
 
-        if ($this->freshRebuild) {
-            $graph->pruneMissingTests();
-        }
-
         if (! $this->saveGraph($graph)) {
             $this->renderBadge('ERROR', 'Could not write the dependency graph.');
 
@@ -598,8 +768,8 @@ final class Tia implements AddsOutput, HandlesArguments, Terminable
                 return $this->reconcileFingerprint($rebuilt, $current);
             }
 
-            $this->state->delete(self::KEY_GRAPH);
+            $this->deleteState(self::KEY_GRAPH);
-            $this->state->delete(self::KEY_COVERAGE_CACHE);
+            $this->deleteState(self::KEY_COVERAGE_CACHE);
 
             return null;
         }
@@ -615,7 +785,7 @@ final class Tia implements AddsOutput, HandlesArguments, Terminable
             $graph->clearResults($this->branch);
             $graph->setFingerprint($current);
             $this->saveGraph($graph);
-            $this->state->delete(self::KEY_COVERAGE_CACHE);
+            $this->deleteState(self::KEY_COVERAGE_CACHE);
         }
 
         return $graph;
@@ -635,12 +805,28 @@ final class Tia implements AddsOutput, HandlesArguments, Terminable
             Panic::with(new TiaRequiresRepositoryRoot($subdirectoryPrefix));
         }
 
-        $this->branch = new ChangedFiles($projectRoot)->currentBranch() ?? 'main';
+        try {
+            $this->resolveBranch($projectRoot);
+        } catch (MissingDependency $missingGit) {
+            $repository = new ChangedFiles($projectRoot);
+
+            if ($repository->isRepository() && ! $repository->hasCommits()) {
+                Panic::with(new TiaRequiresCommit);
+            }
+
+            throw $missingGit;
+        }
+
+        if (! $this->fallbackBranchResolved) {
+            Panic::with(new ChangedFiles($projectRoot)->hasRemote()
+                ? new TiaRequiresDefaultBranch
+                : new TiaRequiresRemote);
+        }
 
         $fingerprint = Fingerprint::compute($projectRoot);
         $this->startFingerprint = $fingerprint;
 
-        if ($forceRebuild) {
+        if ($forceRebuild && ! $this->detachedHead) {
             Storage::purge($projectRoot);
         }
 
@@ -658,6 +844,7 @@ final class Tia implements AddsOutput, HandlesArguments, Terminable
                 && $changedFiles->since($branchSha) === null) {
                 $this->renderBadge('WARN', 'Recorded commit is no longer reachable — graph will be rebuilt.');
                 $graph = null;
+                $this->graphUnreachable = true;
             }
         }
 
@@ -673,13 +860,21 @@ final class Tia implements AddsOutput, HandlesArguments, Terminable
             }
         }
 
-        if ($this->piggybackCoverage) {
+        $coverageCacheOwned = $this->piggybackCoverage && $this->pestCoverageActive();
+
+        if ($coverageCacheOwned) {
             $this->state->write(self::KEY_COVERAGE_MARKER, '');
         }
 
-        if ($this->piggybackCoverage && ! $this->state->exists(self::KEY_COVERAGE_CACHE)) {
+        if (! $graph instanceof Graph && $this->piggybackCoverage) {
-            if ($graph instanceof Graph && $this->driftLabel === null) {
+            $this->emitCoverageScopedRecordSkipped();
-                $this->freshGraphReason = 'recording coverage baseline';
+
+            return $arguments;
+        }
+
+        if ($coverageCacheOwned && ! $this->state->exists(self::KEY_COVERAGE_CACHE)) {
+            if ($this->driftLabel === null) {
+                $this->freshGraphReason = 'recording a coverage baseline';
             }
 
             return $this->enterRecordMode($arguments);
@@ -698,7 +893,7 @@ final class Tia implements AddsOutput, HandlesArguments, Terminable
      */
     private function handleWorker(array $arguments, string $projectRoot, bool $recordingGlobal, bool $replayingGlobal): array
     {
-        $this->branch = new ChangedFiles($projectRoot)->currentBranch() ?? 'main';
+        $this->resolveBranch($projectRoot);
 
         if ($replayingGlobal) {
             $this->installWorkerReplay($projectRoot);
@@ -833,7 +1028,7 @@ final class Tia implements AddsOutput, HandlesArguments, Terminable
             return $arguments;
         }
 
-        $affectedFromChanges = $changed === [] ? [] : $graph->affected($changed);
+        $affectedFromChanges = $changed === [] ? [] : $graph->testFilesOnDisk($graph->affected($changed));
         $rerunFromCache = [];
 
         if ($this->filteredMode && $graph->hasUnlocatedTestsToRerun($this->branch)) {
@@ -875,7 +1070,12 @@ final class Tia implements AddsOutput, HandlesArguments, Terminable
 
         if (! Parallel::isEnabled()) {
             if ($canRefreshReplayEdges) {
-                $this->recorder->activate();
+                if ($this->piggybackCoverage) {
+                    $this->recorder->activateLinkTracking();
+                } else {
+                    $this->recorder->activate();
+                }
+
                 $this->recordingActive = true;
             }
 
@@ -894,6 +1094,10 @@ final class Tia implements AddsOutput, HandlesArguments, Terminable
 
         if ($canRefreshReplayEdges) {
             Parallel::setGlobal(self::RECORDING_GLOBAL, '1');
+
+            if ($this->piggybackCoverage) {
+                Parallel::setGlobal(self::PIGGYBACK_COVERAGE_GLOBAL, '1');
+            }
         }
 
         if ($this->filteredMode) {
@@ -1035,6 +1239,13 @@ final class Tia implements AddsOutput, HandlesArguments, Terminable
         $recorder->activate();
         $this->recordingActive = true;
 
+        if ($this->driftLabel !== null || $this->freshGraphReason !== null) {
+            $this->output->writeln('');
+            $this->renderFreshGraph();
+
+            return $arguments;
+        }
+
         $this->renderChild('Running in TIA mode.');
 
         return $arguments;
@@ -1042,14 +1253,16 @@ final class Tia implements AddsOutput, HandlesArguments, Terminable
 
     private function renderFreshGraph(): void
     {
-        $headline = 'Experimental TIA mode enabled / fresh graph';
+        if ($this->driftLabel === null && $this->freshGraphReason !== null) {
-
+            $headline = sprintf('Experimental TIA mode enabled / %s.', $this->freshGraphReason);
-        if ($this->driftLabel !== null) {
-            $headline .= sprintf(' (%s changed)', $this->driftLabel);
-        } elseif ($this->freshGraphReason !== null) {
-            $headline .= sprintf(' (%s)', $this->freshGraphReason);
         } else {
-            $headline .= '.';
+            $headline = 'Experimental TIA mode enabled / fresh graph';
+
+            if ($this->driftLabel !== null) {
+                $headline .= sprintf(' (%s changed)', $this->driftLabel);
+            } else {
+                $headline .= '.';
+            }
         }
 
         $this->renderChild($headline);
@@ -1065,7 +1278,15 @@ final class Tia implements AddsOutput, HandlesArguments, Terminable
     {
         $this->output->writeln('');
 
-        $this->renderChild('Running in TIA mode, however TIA as skipped as it needs Needs ext-pcov or Xdebug.');
+        $this->renderChild('Running in TIA mode, however TIA is skipped as it needs ext-pcov or Xdebug.');
+    }
+
+    private function emitCoverageScopedRecordSkipped(): void
+    {
+        $this->output->writeln('');
+
+        $this->renderChild('Running in TIA mode, however TIA is skipped as an active coverage report narrows the edges it could record.');
+        $this->renderChild('Record the baseline with a plain --tia run first; coverage runs then reuse it.');
     }
 
     /**
@@ -1115,6 +1336,21 @@ final class Tia implements AddsOutput, HandlesArguments, Terminable
         $this->renderChild('Install / enable pcov or xdebug (mode: coverage) in the worker PHP and rerun.');
     }
 
+    private function requestWorkerResults(): void
+    {
+        if (Parallel::isWorker() || ! Parallel::isEnabled() || $this->writesSuppressed) {
+            return;
+        }
+
+        if ($this->state->read(self::KEY_GRAPH) === null) {
+            return;
+        }
+
+        $this->purgeWorkerPartials();
+
+        Parallel::setGlobal(self::WORKER_RESULTS_GLOBAL, '1');
+    }
+
     private function purgeWorkerPartials(): void
     {
         foreach ($this->collectWorkerEdgesPartials() as $key) {
@@ -1136,11 +1372,16 @@ final class Tia implements AddsOutput, HandlesArguments, Terminable
             return;
         }
 
+        foreach ($results as $testId => $result) {
+            $results[$testId] = $this->replayedAsRecorded($testId, $result);
+        }
+
         $json = json_encode([
             'results' => $results,
             'replayed' => $this->replayedCount,
             'affected' => $this->affectedCount,
             'executed' => $this->executedCount,
+            'truncated' => $this->stoppedEarly() || $collector->hasUnfinishedTest(),
         ], JSON_UNESCAPED_SLASHES);
 
         if ($json === false) {
@@ -1177,6 +1418,10 @@ final class Tia implements AddsOutput, HandlesArguments, Terminable
                 continue;
             }
 
+            if (($decoded['truncated'] ?? false) === true) {
+                $this->resultsOnlyWrites = true;
+            }
+
             if (isset($decoded['replayed']) && is_int($decoded['replayed'])) {
                 $this->replayedCount += $decoded['replayed'];
             }
@@ -1400,6 +1645,29 @@ final class Tia implements AddsOutput, HandlesArguments, Terminable
         return $coverage;
     }
 
+    private function resultTime(string $testId, float $time): float
+    {
+        return $this->cachedTimeByTestId[$testId] ?? $time;
+    }
+
+    /**
+     * @param  array{status: int, message: string, time: float, assertions: int, file?: string}  $result
+     * @return array{status: int, message: string, time: float, assertions: int, file?: string}
+     */
+    private function replayedAsRecorded(string $testId, array $result): array
+    {
+        $result['time'] = $this->resultTime($testId, $result['time']);
+
+        $cached = $this->cachedStatusByTestId[$testId] ?? null;
+
+        if ($cached !== null) {
+            $result['status'] = $cached['status'];
+            $result['message'] = $cached['message'];
+        }
+
+        return $result;
+    }
+
     private function seedResultsInto(Graph $graph): void
     {
         /** @var ResultCollector $collector */
@@ -1419,6 +1687,8 @@ final class Tia implements AddsOutput, HandlesArguments, Terminable
                 $touchedFiles[$file] = true;
             }
 
+            $result = $this->replayedAsRecorded($testId, $result);
+
             $graph->setResult(
                 $this->branch,
                 $testId,
@@ -1432,11 +1702,34 @@ final class Tia implements AddsOutput, HandlesArguments, Terminable
 
         $graph->markKnownTestFiles(array_keys($touchedFiles));
         $graph->pruneStaleResults($this->branch, array_keys($touchedFiles), array_keys($results));
+        $this->reclaim($graph);
 
         $collector->reset();
     }
 
-    private function snapshotTestResults(bool $markKnownTestFiles = false): void
+    private function reclaim(Graph $graph): void
+    {
+        if ($this->branch !== $this->fallbackBranch) {
+            $graph->markBaselineComplete($this->branch);
+        }
+
+        $graph->pruneMissingTests();
+        $graph->pruneResultsForMissingFiles($this->branch);
+
+        $branches = new ChangedFiles(TestSuite::getInstance()->rootPath)->branchNames();
+
+        if ($branches === null) {
+            return;
+        }
+
+        if (! in_array($this->fallbackBranch, $branches, true)) {
+            return;
+        }
+
+        $graph->pruneMissingBranches([...$branches, $this->branch, $this->fallbackBranch]);
+    }
+
+    private function snapshotTestResults(bool $markKnownTestFiles = false, bool $complete = true): void
     {
         /** @var ResultCollector $collector */
         $collector = Container::getInstance()->get(ResultCollector::class);
@@ -1455,8 +1748,17 @@ final class Tia implements AddsOutput, HandlesArguments, Terminable
             return;
         }
 
+        try {
+            $this->resolveBranch($projectRoot);
+        } catch (MissingDependency) {
+        }
+
+        $graph->setFallbackBranch($this->fallbackBranch);
+
         $touchedFiles = [];
 
+        $recordsEdges = $complete && ($markKnownTestFiles || $this->recordingActive);
+
         foreach ($results as $testId => $result) {
             $file = $result['file'] ?? null;
 
@@ -1468,6 +1770,12 @@ final class Tia implements AddsOutput, HandlesArguments, Terminable
                 $touchedFiles[$file] = true;
             }
 
+            if (! $recordsEdges && (! is_string($file) || ! $graph->knowsTest($file))) {
+                continue;
+            }
+
+            $result = $this->replayedAsRecorded($testId, $result);
+
             $graph->setResult(
                 $this->branch,
                 $testId,
@@ -1483,7 +1791,10 @@ final class Tia implements AddsOutput, HandlesArguments, Terminable
             $graph->markKnownTestFiles(array_keys($touchedFiles));
         }
 
-        $graph->pruneStaleResults($this->branch, array_keys($touchedFiles), array_keys($results));
+        if ($complete) {
+            $graph->pruneStaleResults($this->branch, array_keys($touchedFiles), array_keys($results));
+            $this->reclaim($graph);
+        }
 
         $this->saveGraph($graph);
         $collector->reset();
@@ -1521,6 +1832,15 @@ final class Tia implements AddsOutput, HandlesArguments, Terminable
     }
 
     private function coverageReportActive(): bool
+    {
+        if ($this->pestCoverageActive()) {
+            return true;
+        }
+
+        return array_any(self::COVERAGE_REPORT_FLAGS, fn (string $flag): bool => $this->hasArgument($flag, $this->originalArguments));
+    }
+
+    private function pestCoverageActive(): bool
     {
         $coverage = Container::getInstance()->get(Coverage::class);
         assert($coverage instanceof Coverage);
@@ -1528,6 +1848,105 @@ final class Tia implements AddsOutput, HandlesArguments, Terminable
         return $coverage->coverage;
     }
 
+    /**
+     * @param  array<int, string>  $arguments
+     */
+    private function guardUnsupportedOptions(array $arguments): void
+    {
+        foreach (self::UNSUPPORTED_OPTIONS as $option) {
+            if (! $this->hasArgument($option, $arguments) && ! $this->hasArgument($option, $this->originalArguments)) {
+                continue;
+            }
+
+            Panic::with(new InvalidOption(sprintf(
+                'The [%s] option cannot be combined with [%s].',
+                $option,
+                self::OPTION,
+            )));
+        }
+    }
+
+    /**
+     * @param  array<int, string>  $arguments
+     */
+    private function hasPartialSelection(array $arguments): bool
+    {
+        foreach (self::PARTIAL_SELECTION_FLAGS as $flag) {
+            if ($this->hasArgument($flag, $arguments)) {
+                return true;
+            }
+
+            if ($this->hasArgument($flag, $this->originalArguments)) {
+                return true;
+            }
+        }
+
+        return false;
+    }
+
+    private function stoppedEarly(): bool
+    {
+        return TestResultFacade::shouldStop();
+    }
+
+    private function hasUnfinishedTest(): bool
+    {
+        $collector = Container::getInstance()->get(ResultCollector::class);
+        assert($collector instanceof ResultCollector);
+
+        return $collector->hasUnfinishedTest();
+    }
+
+    private function resolveBranch(string $projectRoot): void
+    {
+        if ($this->branchResolved) {
+            return;
+        }
+
+        $this->branchResolved = true;
+
+        $changedFiles = new ChangedFiles($projectRoot);
+
+        $resolved = $this->resolveFallbackBranch($changedFiles);
+
+        $this->fallbackBranchResolved = $resolved !== null;
+        $this->fallbackBranch = $resolved ?? self::DEFAULT_BRANCH;
+
+        Parallel::setGlobal(self::FALLBACK_BRANCH_GLOBAL, $this->fallbackBranch);
+
+        $currentBranch = $changedFiles->currentBranch();
+
+        $this->detachedHead = $currentBranch === null;
+        $this->branch = $currentBranch ?? $this->fallbackBranch;
+    }
+
+    private function resolveFallbackBranch(ChangedFiles $changedFiles): ?string
+    {
+        $inherited = Parallel::getGlobal(self::FALLBACK_BRANCH_GLOBAL);
+
+        if (is_string($inherited) && $inherited !== '') {
+            return $inherited;
+        }
+
+        return $this->watchPatterns->defaultBranch()
+            ?? CiDefaultBranch::detect()
+            ?? $changedFiles->defaultBranch()
+            ?? $this->soleRecordedBranch();
+    }
+
+    private function soleRecordedBranch(): ?string
+    {
+        $json = $this->state->read(self::KEY_GRAPH);
+
+        if ($json === null) {
+            return null;
+        }
+
+        $branches = Graph::branchesIn($json);
+
+        return count($branches) === 1 ? $branches[0] : null;
+    }
+
     /**
      * @param  array<int, string>  $arguments
      */
@@ -1549,11 +1968,15 @@ final class Tia implements AddsOutput, HandlesArguments, Terminable
             if (str_starts_with($arg, '-')) {
                 continue;
             }
-            if ($index > 0) {
+
-                $previous = $arguments[$index - 1] ?? '';
+            if ($index === 0) {
-                if (in_array($previous, self::VALUE_TAKING_FLAGS, true)) {
+                continue;
-                    continue;
+            }
-                }
+
+            $previous = $arguments[$index - 1] ?? '';
+
+            if (in_array($previous, self::VALUE_TAKING_FLAGS, true)) {
+                continue;
             }
 
             $candidate = $this->resolveArgumentPath($arg, $projectRoot);
@@ -1562,16 +1985,28 @@ final class Tia implements AddsOutput, HandlesArguments, Terminable
                 continue;
             }
 
-            foreach ($testPaths as $testPath) {
+            if ($this->narrowsSuite($candidate, $testPaths)) {
-                if ($candidate === $testPath || str_starts_with($candidate, $testPath.DIRECTORY_SEPARATOR)) {
+                return true;
-                    return true;
-                }
             }
         }
 
         return false;
     }
 
+    /**
+     * @param  array<int, string>  $testPaths
+     */
+    private function narrowsSuite(string $candidate, array $testPaths): bool
+    {
+        foreach ($testPaths as $testPath) {
+            if ($candidate === $testPath || str_starts_with($candidate, $testPath.DIRECTORY_SEPARATOR)) {
+                return true;
+            }
+        }
+
+        return array_all($testPaths, fn (string $testPath): bool => ! str_starts_with($testPath, $candidate.DIRECTORY_SEPARATOR));
+    }
+
     private function resolveArgumentPath(string $arg, string $projectRoot): ?string
     {
         $candidates = [$arg, rtrim($projectRoot, DIRECTORY_SEPARATOR).DIRECTORY_SEPARATOR.ltrim($arg, DIRECTORY_SEPARATOR)];
@@ -1701,16 +2136,7 @@ final class Tia implements AddsOutput, HandlesArguments, Terminable
      */
     private function gitSubdirectoryPrefix(string $projectRoot): ?string
     {
-        $process = new Process(['git', 'rev-parse', '--show-prefix'], $projectRoot);
+        return new Git($projectRoot)->subdirectoryPrefix();
-        $process->run();
-
-        if (! $process->isSuccessful()) {
-            return null;
-        }
-
-        $prefix = trim($process->getOutput());
-
-        return $prefix === '' ? null : rtrim(str_replace(DIRECTORY_SEPARATOR, '/', $prefix), '/');
     }
 
     private function composerLockDelta(string $projectRoot, string $sha): string
@@ -1720,15 +2146,13 @@ final class Tia implements AddsOutput, HandlesArguments, Terminable
             return '';
         }
 
-        $process = new Process(['git', 'show', $sha.':composer.lock'], $projectRoot);
+        $baseline = new Git($projectRoot)->show($sha, 'composer.lock');
-        $process->setTimeout(5.0);
-        $process->run();
 
-        if (! $process->isSuccessful()) {
+        if ($baseline === null) {
             return '';
         }
 
-        $oldVersions = $this->lockVersions($process->getOutput());
+        $oldVersions = $this->lockVersions($baseline);
         $newVersions = $this->lockVersions($current);
 
         if ($oldVersions === [] && $newVersions === []) {

src/Plugins/Tia/ChangedFiles.php

@@ -5,14 +5,19 @@ declare(strict_types=1);
 namespace Pest\Plugins\Tia;
 
 use Pest\Exceptions\MissingDependency;
-use Symfony\Component\Process\Process;
+use Pest\Support\Git;
 
 /**
  * @internal
  */
 final readonly class ChangedFiles
 {
-    public function __construct(private string $projectRoot) {}
+    private Git $git;
+
+    public function __construct(private string $projectRoot)
+    {
+        $this->git = new Git($projectRoot);
+    }
 
     /**
      * @param  array<int, string>  $files  project-relative paths.
@@ -155,15 +160,7 @@ final readonly class ChangedFiles
 
     private function contentAtSha(string $sha, string $path): ?string
     {
-        $process = new Process(['git', 'show', $sha.':'.$path], $this->projectRoot);
+        return $this->git->show($sha, $path);
-        $process->setTimeout(5.0);
-        $process->run();
-
-        if (! $process->isSuccessful()) {
-            return null;
-        }
-
-        return $process->getOutput();
     }
 
     /**
@@ -176,21 +173,17 @@ final readonly class ChangedFiles
             return $candidates;
         }
 
-        $process = new Process(
+        $result = $this->git->result(
-            ['git', 'check-ignore', '--no-index', '-z', '--stdin'],
+            ['check-ignore', '--no-index', '-z', '--stdin'],
-            $this->projectRoot,
+            implode("\x00", array_keys($candidates)),
         );
-        $process->setTimeout(5.0);
-        $process->setInput(implode("\x00", array_keys($candidates)));
-        $process->run();
 
-        $exitCode = $process->getExitCode();
+        // `check-ignore` exits 1 when nothing matched — that is not a failure.
-
+        if ($result['exitCode'] !== 0 && $result['exitCode'] !== 1) {
-        if ($exitCode !== 0 && $exitCode !== 1) {
             throw new MissingDependency('Tia mode', 'git');
         }
 
-        $output = $process->getOutput();
+        $output = $result['output'];
 
         if ($output === '') {
             return $candidates;
@@ -207,27 +200,109 @@ final readonly class ChangedFiles
 
     public function currentBranch(): ?string
     {
-        $process = new Process(['git', 'rev-parse', '--abbrev-ref', 'HEAD'], $this->projectRoot);
+        $output = $this->git->raw(['rev-parse', '--abbrev-ref', 'HEAD']);
-        $process->run();
 
-        if (! $process->isSuccessful()) {
+        if ($output === null) {
             throw new MissingDependency('Tia mode', 'git');
         }
 
-        $branch = trim($process->getOutput());
+        $branch = trim($output);
 
         return $branch === '' || $branch === 'HEAD' ? null : $branch;
     }
 
+    public function defaultBranch(): ?string
+    {
+        $head = $this->git->output(['symbolic-ref', '--short', 'refs/remotes/origin/HEAD']);
+
+        if ($head !== null) {
+            $branch = preg_replace('#^origin/#', '', $head);
+
+            if (is_string($branch) && $branch !== '') {
+                return $branch;
+            }
+        }
+
+        $configured = $this->git->output(['config', '--get', 'init.defaultBranch']);
+
+        if ($configured === null) {
+            return null;
+        }
+
+        $exists = $this->git->hasRef('refs/heads/'.$configured)
+            || $this->git->hasRef('refs/remotes/origin/'.$configured);
+
+        return $exists ? $configured : null;
+    }
+
+    /**
+     * @return list<string>|null
+     */
+    public function branchNames(): ?array
+    {
+        $output = $this->git->raw(['for-each-ref', '--format=%(refname)', 'refs/heads', 'refs/remotes']);
+
+        if ($output === null) {
+            return null;
+        }
+
+        $names = [];
+
+        foreach ($this->splitLines($output) as $ref) {
+            if (str_starts_with($ref, 'refs/heads/')) {
+                $names[substr($ref, strlen('refs/heads/'))] = true;
+
+                continue;
+            }
+
+            if (! str_starts_with($ref, 'refs/remotes/')) {
+                continue;
+            }
+
+            $tail = substr($ref, strlen('refs/remotes/'));
+            $slash = strpos($tail, '/');
+
+            if ($slash === false) {
+                continue;
+            }
+
+            $branch = substr($tail, $slash + 1);
+
+            if ($branch !== '' && $branch !== 'HEAD') {
+                $names[$branch] = true;
+            }
+        }
+
+        return array_keys($names);
+    }
+
+    public function hasRemote(): bool
+    {
+        return $this->git->hasRemote();
+    }
+
+    public function isRepository(): bool
+    {
+        return $this->git->isRepository();
+    }
+
+    public function hasCommits(): bool
+    {
+        return $this->git->hasCommits();
+    }
+
+    /**
+     * Working-tree scans get a longer leash than metadata queries — on a large
+     * repository with a cold cache, `status` and `diff` are not instant.
+     */
+    private function scan(): Git
+    {
+        return $this->git->withTimeout(60.0);
+    }
+
     private function shaIsReachable(string $sha): bool
     {
-        $process = new Process(
+        return $this->git->succeeds(['merge-base', '--is-ancestor', $sha, 'HEAD']);
-            ['git', 'merge-base', '--is-ancestor', $sha, 'HEAD'],
-            $this->projectRoot,
-        );
-        $process->run();
-
-        return $process->getExitCode() === 0;
     }
 
     /**
@@ -235,17 +310,13 @@ final readonly class ChangedFiles
      */
     private function diffSinceSha(string $sha): array
     {
-        $process = new Process(
+        $output = $this->scan()->raw(['diff', '--name-only', '--no-renames', $sha.'..HEAD']);
-            ['git', 'diff', '--name-only', $sha.'..HEAD'],
-            $this->projectRoot,
-        );
-        $process->run();
 
-        if (! $process->isSuccessful()) {
+        if ($output === null) {
             throw new MissingDependency('Tia mode', 'git');
         }
 
-        return $this->splitLines($process->getOutput());
+        return $this->splitLines($output);
     }
 
     /**
@@ -253,18 +324,12 @@ final readonly class ChangedFiles
      */
     private function workingTreeChanges(): array
     {
-        $process = new Process(
+        $output = $this->scan()->raw(['status', '--porcelain', '-z', '--untracked-files=all']);
-            ['git', 'status', '--porcelain', '-z', '--untracked-files=all'],
-            $this->projectRoot,
-        );
-        $process->run();
 
-        if (! $process->isSuccessful()) {
+        if ($output === null) {
             throw new MissingDependency('Tia mode', 'git');
         }
 
-        $output = $process->getOutput();
-
         if ($output === '') {
             return [];
         }
@@ -302,14 +367,13 @@ final readonly class ChangedFiles
 
     public function currentSha(): ?string
     {
-        $process = new Process(['git', 'rev-parse', 'HEAD'], $this->projectRoot);
+        $output = $this->git->raw(['rev-parse', 'HEAD']);
-        $process->run();
 
-        if (! $process->isSuccessful()) {
+        if ($output === null) {
             throw new MissingDependency('Tia mode', 'git');
         }
 
-        $sha = trim($process->getOutput());
+        $sha = trim($output);
 
         return $sha === '' ? null : $sha;
     }

src/Plugins/Tia/CiDefaultBranch.php

@@ -0,0 +1,34 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Pest\Plugins\Tia;
+
+use Pest\Plugins\Tia\Contracts\Ci;
+
+/**
+ * @internal
+ */
+final class CiDefaultBranch
+{
+    /**
+     * @var array<int, class-string<Ci>>
+     */
+    private const array CIS = [
+        Cis\GitLab::class,
+        Cis\GitHub::class,
+    ];
+
+    public static function detect(): ?string
+    {
+        foreach (self::CIS as $class) {
+            $branch = (new $class)->defaultBranch();
+
+            if ($branch !== null) {
+                return $branch;
+            }
+        }
+
+        return null;
+    }
+}

src/Plugins/Tia/Cis/Concerns/ReadsEnvironment.php

@@ -0,0 +1,24 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Pest\Plugins\Tia\Cis\Concerns;
+
+/**
+ * @internal
+ */
+trait ReadsEnvironment
+{
+    private function environment(string $name): ?string
+    {
+        $value = getenv($name);
+
+        if (! is_string($value)) {
+            return null;
+        }
+
+        $value = trim($value);
+
+        return $value === '' ? null : $value;
+    }
+}

src/Plugins/Tia/Cis/GitHub.php

@@ -0,0 +1,41 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Pest\Plugins\Tia\Cis;
+
+use Pest\Plugins\Tia\Cis\Concerns\ReadsEnvironment;
+use Pest\Plugins\Tia\Contracts\Ci;
+
+/**
+ * @internal
+ */
+final readonly class GitHub implements Ci
+{
+    use ReadsEnvironment;
+
+    public function defaultBranch(): ?string
+    {
+        $path = $this->environment('GITHUB_EVENT_PATH');
+
+        if ($path === null || ! is_file($path) || ! is_readable($path)) {
+            return null;
+        }
+
+        $contents = @file_get_contents($path);
+
+        if ($contents === false) {
+            return null;
+        }
+
+        $payload = json_decode($contents, true);
+
+        if (! is_array($payload) || ! is_array($payload['repository'] ?? null)) {
+            return null;
+        }
+
+        $branch = $payload['repository']['default_branch'] ?? null;
+
+        return is_string($branch) && $branch !== '' ? $branch : null;
+    }
+}

src/Plugins/Tia/Cis/GitLab.php

@@ -0,0 +1,21 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Pest\Plugins\Tia\Cis;
+
+use Pest\Plugins\Tia\Cis\Concerns\ReadsEnvironment;
+use Pest\Plugins\Tia\Contracts\Ci;
+
+/**
+ * @internal
+ */
+final readonly class GitLab implements Ci
+{
+    use ReadsEnvironment;
+
+    public function defaultBranch(): ?string
+    {
+        return $this->environment('CI_DEFAULT_BRANCH');
+    }
+}

src/Plugins/Tia/Configuration.php

@@ -60,6 +60,18 @@ final class Configuration
         return $this;
     }
 
+    /**
+     * @return $this
+     */
+    public function defaultBranch(string $branch): self
+    {
+        /** @var WatchPatterns $watchPatterns */
+        $watchPatterns = Container::getInstance()->get(WatchPatterns::class);
+        $watchPatterns->setDefaultBranch($branch);
+
+        return $this;
+    }
+
     /**
      * @param  array<string, string>  $patterns  glob → project-relative test dir
      * @return $this

src/Plugins/Tia/Contracts/Ci.php

@@ -0,0 +1,17 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Pest\Plugins\Tia\Contracts;
+
+/**
+ * @internal
+ */
+interface Ci
+{
+    /**
+     * The default branch advertised by this CI, or `null` when the run
+     * does not happen on it — or when it exposes no such information.
+     */
+    public function defaultBranch(): ?string;
+}

src/Plugins/Tia/Enums/ReplayType.php

@@ -29,7 +29,9 @@ enum ReplayType
             $status->isRisky() => self::Risky,
             $status->isSkipped() => self::Skipped,
             $status->isIncomplete() => self::Incomplete,
-            default => self::Failure,
+            $status->isNotice(), $status->isDeprecation(), $status->isWarning() => self::Pass,
+            $status->isFailure(), $status->isError() => self::Failure,
+            default => self::None,
         };
     }
 }

src/Plugins/Tia/Graph.php

@@ -43,11 +43,14 @@ final class Graph
      * @var array<string, array{
      *     sha: ?string,
      *     tree: array<string, string>,
+     *     complete?: bool,
      *     results: array<string, array{status: int, message: string, time: float, assertions?: int, file?: string}>
      * }>
      */
     private array $baselines = [];
 
+    private string $fallbackBranch = 'main';
+
     private readonly string $projectRoot;
 
     /** @var array<string, true>|null */
@@ -116,6 +119,24 @@ final class Graph
         return array_keys($affectedSet);
     }
 
+    /**
+     * @param  array<int, string>  $testFiles  Project-relative paths.
+     * @return list<string>
+     */
+    public function testFilesOnDisk(array $testFiles): array
+    {
+        $root = rtrim($this->projectRoot, DIRECTORY_SEPARATOR).DIRECTORY_SEPARATOR;
+        $onDisk = [];
+
+        foreach ($testFiles as $testFile) {
+            if (is_file($root.$testFile)) {
+                $onDisk[] = $testFile;
+            }
+        }
+
+        return $onDisk;
+    }
+
     /**
      * @param  array<int, string>  $changedFiles
      * @return array{0: list<string>, 1: list<string>}
@@ -576,7 +597,12 @@ final class Graph
         return $this->fingerprint;
     }
 
-    public function recordedAtSha(string $branch, string $fallbackBranch = 'main'): ?string
+    public function setFallbackBranch(string $branch): void
+    {
+        $this->fallbackBranch = $branch;
+    }
+
+    public function recordedAtSha(string $branch, ?string $fallbackBranch = null): ?string
     {
         $baseline = $this->baselineFor($branch, $fallbackBranch);
 
@@ -611,7 +637,7 @@ final class Graph
         $this->baselines[$branch]['results'][$testId] = $entry;
     }
 
-    public function getAssertions(string $branch, string $testId, string $fallbackBranch = 'main'): ?int
+    public function getAssertions(string $branch, string $testId, ?string $fallbackBranch = null): ?int
     {
         $baseline = $this->baselineFor($branch, $fallbackBranch);
 
@@ -622,7 +648,18 @@ final class Graph
         return $baseline['results'][$testId]['assertions'];
     }
 
-    public function getResult(string $branch, string $testId, string $fallbackBranch = 'main'): ?TestStatus
+    public function getTime(string $branch, string $testId, ?string $fallbackBranch = null): ?float
+    {
+        $baseline = $this->baselineFor($branch, $fallbackBranch);
+
+        if (! isset($baseline['results'][$testId]['time'])) {
+            return null;
+        }
+
+        return $baseline['results'][$testId]['time'];
+    }
+
+    public function getResult(string $branch, string $testId, ?string $fallbackBranch = null): ?TestStatus
     {
         $baseline = $this->baselineFor($branch, $fallbackBranch);
 
@@ -642,14 +679,14 @@ final class Graph
             6 => TestStatus::warning($r['message']),
             7 => TestStatus::failure($r['message']),
             8 => TestStatus::error($r['message']),
-            default => TestStatus::unknown(),
+            default => null,
         };
     }
 
     /**
      * @return array<int, string>
      */
-    public function testFilesToRerun(string $branch, string $fallbackBranch = 'main'): array
+    public function testFilesToRerun(string $branch, ?string $fallbackBranch = null): array
     {
         $baseline = $this->baselineFor($branch, $fallbackBranch);
         $files = [];
@@ -669,7 +706,7 @@ final class Graph
 
             $rel = $this->relative($file);
 
-            if ($rel !== null) {
+            if ($rel !== null && is_file($this->projectRoot.'/'.$rel)) {
                 $files[$rel] = true;
             }
         }
@@ -677,7 +714,7 @@ final class Graph
         return array_keys($files);
     }
 
-    public function hasUnlocatedTestsToRerun(string $branch, string $fallbackBranch = 'main'): bool
+    public function hasUnlocatedTestsToRerun(string $branch, ?string $fallbackBranch = null): bool
     {
         $baseline = $this->baselineFor($branch, $fallbackBranch);
 
@@ -688,7 +725,11 @@ final class Graph
 
             $file = $result['file'] ?? null;
 
-            if ($file === null || $file === '' || $this->relative($file) === null) {
+            if ($file === null || $file === '') {
+                return true;
+            }
+
+            if ($this->relative($file) === null) {
                 return true;
             }
         }
@@ -712,6 +753,10 @@ final class Graph
             return true;
         }
 
+        if ($testStatus->isUnknown()) {
+            return true;
+        }
+
         $configuration = Registry::get();
 
         if ($testStatus->isRisky()) {
@@ -779,25 +824,70 @@ final class Graph
     /**
      * @return array<string, string>
      */
-    public function lastRunTree(string $branch, string $fallbackBranch = 'main'): array
+    public function lastRunTree(string $branch, ?string $fallbackBranch = null): array
     {
         return $this->baselineFor($branch, $fallbackBranch)['tree'];
     }
 
     /**
-     * @return array{sha: ?string, tree: array<string, string>, results: array<string, array{status: int, message: string, time: float, assertions?: int, file?: string}>}
+     * @return array{sha: ?string, tree: array<string, string>, complete?: bool, results: array<string, array{status: int, message: string, time: float, assertions?: int, file?: string}>}
      */
-    private function baselineFor(string $branch, string $fallbackBranch): array
+    private function baselineFor(string $branch, ?string $fallbackBranch): array
     {
-        if (isset($this->baselines[$branch])) {
+        $fallbackBranch ??= $this->fallbackBranch;
-            return $this->baselines[$branch];
+
+        $fallback = $branch !== $fallbackBranch ? ($this->baselines[$fallbackBranch] ?? null) : null;
+        $own = $this->baselines[$branch] ?? null;
+
+        if ($own === null) {
+            return $fallback ?? ['sha' => null, 'tree' => [], 'results' => []];
         }
 
-        if ($branch !== $fallbackBranch && isset($this->baselines[$fallbackBranch])) {
+        if ($fallback === null) {
-            return $this->baselines[$fallbackBranch];
+            return $own;
         }
 
-        return ['sha' => null, 'tree' => [], 'results' => []];
+        $under = ($own['complete'] ?? false) === true
+            ? $this->withoutFilesCoveredBy($fallback['results'], $own['results'])
+            : $fallback['results'];
+
+        return [
+            'sha' => $own['sha'] ?? $fallback['sha'],
+            'tree' => $own['tree'] !== [] ? $own['tree'] : $fallback['tree'],
+            'results' => array_replace($under, $own['results']),
+        ];
+    }
+
+    /**
+     * @param  array<string, array{status: int, message: string, time: float, assertions?: int, file?: string}>  $results
+     * @param  array<string, array{status: int, message: string, time: float, assertions?: int, file?: string}>  $authoritative
+     * @return array<string, array{status: int, message: string, time: float, assertions?: int, file?: string}>
+     */
+    private function withoutFilesCoveredBy(array $results, array $authoritative): array
+    {
+        $covered = [];
+
+        foreach ($authoritative as $entry) {
+            $file = $entry['file'] ?? null;
+
+            if (is_string($file) && $file !== '') {
+                $covered[$file] = true;
+            }
+        }
+
+        if ($covered === []) {
+            return $results;
+        }
+
+        foreach ($results as $testId => $entry) {
+            $file = $entry['file'] ?? null;
+
+            if (is_string($file) && isset($covered[$file])) {
+                unset($results[$testId]);
+            }
+        }
+
+        return $results;
     }
 
     private function ensureBaseline(string $branch): void
@@ -809,8 +899,9 @@ final class Graph
 
     /**
      * @param  array<string, array<int, string>>  $testToFiles
+     * @param  bool  $keepExisting  Leave already-recorded edge sets alone.
      */
-    public function replaceEdges(array $testToFiles): void
+    public function replaceEdges(array $testToFiles, bool $keepExisting = false): void
     {
         foreach ($testToFiles as $testFile => $sources) {
             $testRel = $this->relative($testFile);
@@ -819,6 +910,10 @@ final class Graph
                 continue;
             }
 
+            if ($keepExisting && ($this->edges[$testRel] ?? []) !== []) {
+                continue;
+            }
+
             $this->edges[$testRel] = [];
 
             foreach ($sources as $source) {
@@ -1377,6 +1472,56 @@ final class Graph
         }
     }
 
+    public function markBaselineComplete(string $branch): void
+    {
+        if (isset($this->baselines[$branch])) {
+            $this->baselines[$branch]['complete'] = true;
+        }
+    }
+
+    public function pruneResultsForMissingFiles(string $branch): void
+    {
+        if (! isset($this->baselines[$branch]['results'])) {
+            return;
+        }
+
+        $root = rtrim($this->projectRoot, DIRECTORY_SEPARATOR).DIRECTORY_SEPARATOR;
+
+        foreach ($this->baselines[$branch]['results'] as $testId => $result) {
+            $file = $result['file'] ?? null;
+            if (! is_string($file)) {
+                continue;
+            }
+            if ($file === '') {
+                continue;
+            }
+
+            $rel = $this->relative($file);
+            if ($rel === null) {
+                continue;
+            }
+            if (is_file($root.$rel)) {
+                continue;
+            }
+
+            unset($this->baselines[$branch]['results'][$testId]);
+        }
+    }
+
+    /**
+     * @param  array<int, string>  $keep
+     */
+    public function pruneMissingBranches(array $keep): void
+    {
+        $survivors = array_fill_keys($keep, true);
+
+        foreach (array_keys($this->baselines) as $branch) {
+            if (! isset($survivors[$branch])) {
+                unset($this->baselines[$branch]);
+            }
+        }
+    }
+
     /**
      * Prune baseline result entries whose test files were just executed but whose
      * test IDs are no longer present (e.g. the test method was removed or renamed).
@@ -1422,6 +1567,28 @@ final class Graph
         }
     }
 
+    /**
+     * @return list<string>
+     */
+    public static function branchesIn(string $json): array
+    {
+        $data = json_decode($json, true);
+
+        if (! is_array($data) || ! is_array($data['baselines'] ?? null)) {
+            return [];
+        }
+
+        $branches = [];
+
+        foreach (array_keys($data['baselines']) as $branch) {
+            if (is_string($branch) && $branch !== '') {
+                $branches[] = $branch;
+            }
+        }
+
+        return $branches;
+    }
+
     public static function decode(string $json, string $projectRoot): ?self
     {
         $data = json_decode($json, true);
@@ -1432,10 +1599,10 @@ final class Graph
 
         $graph = new self($projectRoot);
         $graph->fingerprint = is_array($data['fingerprint'] ?? null) ? $data['fingerprint'] : [];
-        $graph->files = is_array($data['files'] ?? null) ? array_values($data['files']) : [];
+        $graph->files = self::decodeFiles($data['files'] ?? null);
         $graph->fileIds = array_flip($graph->files);
-        $graph->edges = is_array($data['edges'] ?? null) ? $data['edges'] : [];
+        $graph->edges = self::decodeEdges($data['edges'] ?? null);
-        $graph->baselines = is_array($data['baselines'] ?? null) ? $data['baselines'] : [];
+        $graph->baselines = self::decodeBaselines($data['baselines'] ?? null);
 
         $graph->testTables = self::decodeStringMap($data['test_tables'] ?? null);
         $graph->testInertiaComponents = self::decodeStringMap($data['test_inertia_components'] ?? null);
@@ -1444,6 +1611,153 @@ final class Graph
         return $graph;
     }
 
+    /**
+     * @return array<int, string>
+     */
+    private static function decodeFiles(mixed $section): array
+    {
+        if (! is_array($section)) {
+            return [];
+        }
+
+        $files = [];
+
+        foreach ($section as $path) {
+            if (is_string($path) && $path !== '') {
+                $files[] = $path;
+            }
+        }
+
+        return $files;
+    }
+
+    /**
+     * @return array<string, array<int, int>>
+     */
+    private static function decodeEdges(mixed $section): array
+    {
+        if (! is_array($section)) {
+            return [];
+        }
+
+        $edges = [];
+
+        foreach ($section as $key => $ids) {
+            $testFile = (string) $key;
+
+            if ($testFile === '') {
+                continue;
+            }
+            if (! is_array($ids)) {
+                continue;
+            }
+
+            $clean = [];
+
+            foreach ($ids as $id) {
+                if (is_int($id)) {
+                    $clean[] = $id;
+                }
+            }
+
+            $edges[$testFile] = $clean;
+        }
+
+        return $edges;
+    }
+
+    /**
+     * @return array<string, array{sha: ?string, tree: array<string, string>, complete?: bool, results: array<string, array{status: int, message: string, time: float, assertions?: int, file?: string}>}>
+     */
+    private static function decodeBaselines(mixed $section): array
+    {
+        if (! is_array($section)) {
+            return [];
+        }
+
+        $baselines = [];
+
+        foreach ($section as $key => $baseline) {
+            $branch = (string) $key;
+
+            if ($branch === '') {
+                continue;
+            }
+            if (! is_array($baseline)) {
+                continue;
+            }
+
+            $sha = $baseline['sha'] ?? null;
+            $tree = [];
+
+            if (is_array($baseline['tree'] ?? null)) {
+                foreach ($baseline['tree'] as $path => $hash) {
+                    if (is_string($path) && is_string($hash)) {
+                        $tree[$path] = $hash;
+                    }
+                }
+            }
+
+            $baselines[$branch] = [
+                'sha' => is_string($sha) ? $sha : null,
+                'tree' => $tree,
+                'results' => self::decodeResults($baseline['results'] ?? null),
+            ];
+
+            if (($baseline['complete'] ?? null) === true) {
+                $baselines[$branch]['complete'] = true;
+            }
+        }
+
+        return $baselines;
+    }
+
+    /**
+     * @return array<string, array{status: int, message: string, time: float, assertions?: int, file?: string}>
+     */
+    private static function decodeResults(mixed $section): array
+    {
+        if (! is_array($section)) {
+            return [];
+        }
+
+        $results = [];
+
+        foreach ($section as $key => $entry) {
+            $testId = (string) $key;
+
+            if ($testId === '') {
+                continue;
+            }
+            if (! is_array($entry)) {
+                continue;
+            }
+            if (! is_int($entry['status'] ?? null)) {
+                continue;
+            }
+
+            $time = $entry['time'] ?? null;
+
+            $result = [
+                'status' => $entry['status'],
+                'message' => is_string($entry['message'] ?? null) ? $entry['message'] : '',
+                'time' => is_int($time) || is_float($time) ? (float) $time : 0.0,
+            ];
+
+            if (is_int($entry['assertions'] ?? null)) {
+                $result['assertions'] = $entry['assertions'];
+            }
+
+            if (is_string($entry['file'] ?? null) && $entry['file'] !== '') {
+                $result['file'] = $entry['file'];
+            }
+
+            $results[$testId] = $result;
+        }
+
+        return $results;
+    }
+
     /**
      * @return array<string, list<string>>
      */

src/Plugins/Tia/Recorder.php

@@ -68,7 +68,7 @@ final class Recorder
     public function driverAvailable(): bool
     {
         if (! $this->driverChecked) {
-            if (function_exists('pcov\\start')) {
+            if (function_exists('pcov\\start') && filter_var((string) ini_get('pcov.enabled'), FILTER_VALIDATE_BOOL)) {
                 $this->driver = 'pcov';
                 $this->driverAvailable = true;
             } elseif (function_exists('xdebug_start_code_coverage') && function_exists('xdebug_info')) {
@@ -360,7 +360,9 @@ final class Recorder
             }
 
             $lineKeys = array_keys($lines);
-            if ($lineKeys !== [] && count($covered) === 1 && $covered[0] === max($lineKeys)) {
+            $reportsUnexecutedLines = count($covered) < count($lines);
+
+            if ($reportsUnexecutedLines && $lineKeys !== [] && count($covered) === 1 && $covered[0] === max($lineKeys)) {
                 continue;
             }
 

src/Plugins/Tia/ResultCollector.php

@@ -16,6 +16,9 @@ final class ResultCollector
      */
     private array $results = [];
 
+    /** @var array<string, true> */
+    private array $triggered = [];
+
     private ?string $currentTestId = null;
 
     private ?string $currentTestFile = null;
@@ -35,9 +38,30 @@ final class ResultCollector
             return;
         }
 
+        if (isset($this->triggered[$this->currentTestId])) {
+            $this->refreshTime();
+
+            return;
+        }
+
         $this->record(TestStatus::success());
     }
 
+    public function testTriggeredNotice(string $message): void
+    {
+        $this->recordIssue(TestStatus::notice($message));
+    }
+
+    public function testTriggeredDeprecation(string $message): void
+    {
+        $this->recordIssue(TestStatus::deprecation($message));
+    }
+
+    public function testTriggeredWarning(string $message): void
+    {
+        $this->recordIssue(TestStatus::warning($message));
+    }
+
     public function testFailed(string $message): void
     {
         if ($this->currentTestId === null) {
@@ -91,6 +115,11 @@ final class ResultCollector
         return $this->results;
     }
 
+    public function hasUnfinishedTest(): bool
+    {
+        return $this->currentTestId !== null;
+    }
+
     public function recordAssertions(string $testId, int $assertions): void
     {
         if (isset($this->results[$testId])) {
@@ -111,6 +140,7 @@ final class ResultCollector
     public function reset(): void
     {
         $this->results = [];
+        $this->triggered = [];
         $this->currentTestId = null;
         $this->currentTestFile = null;
         $this->startTime = null;
@@ -123,6 +153,38 @@ final class ResultCollector
         $this->startTime = null;
     }
 
+    private function recordIssue(TestStatus $status): void
+    {
+        if ($this->currentTestId === null) {
+            return;
+        }
+
+        $existing = $this->results[$this->currentTestId]['status'] ?? null;
+
+        if (is_int($existing) && $existing >= $status->asInt()) {
+            return;
+        }
+
+        $this->triggered[$this->currentTestId] = true;
+
+        $this->record($status);
+    }
+
+    private function refreshTime(): void
+    {
+        if ($this->currentTestId === null) {
+            return;
+        }
+        if (! isset($this->results[$this->currentTestId])) {
+            return;
+        }
+        if ($this->startTime === null) {
+            return;
+        }
+
+        $this->results[$this->currentTestId]['time'] = round(microtime(true) - $this->startTime, 3);
+    }
+
     private function record(TestStatus $status): void
     {
         if ($this->currentTestId === null) {

src/Plugins/Tia/TableExtractor.php

@@ -56,7 +56,7 @@ final class TableExtractor
             $tables[strtolower($name)] = true;
         }
 
-        $out = array_keys($tables);
+        $out = array_map(strval(...), array_keys($tables));
         sort($out);
 
         return $out;
@@ -112,7 +112,7 @@ final class TableExtractor
             }
         }
 
-        $out = array_keys($tables);
+        $out = array_map(strval(...), array_keys($tables));
         sort($out);
 
         return $out;

src/Plugins/Tia/WatchPatterns.php

@@ -44,6 +44,8 @@ final class WatchPatterns
 
     private bool $baselined = false;
 
+    private ?string $defaultBranch = null;
+
     public function useDefaults(string $projectRoot): void
     {
         $testPath = TestSuite::getInstance()->testPath;
@@ -177,6 +179,16 @@ final class WatchPatterns
         return $this->baselined;
     }
 
+    public function setDefaultBranch(string $branch): void
+    {
+        $this->defaultBranch = $branch;
+    }
+
+    public function defaultBranch(): ?string
+    {
+        return $this->defaultBranch;
+    }
+
     public function reset(): void
     {
         $this->patterns = [];
@@ -185,6 +197,7 @@ final class WatchPatterns
         $this->locally = false;
         $this->filtered = false;
         $this->baselined = false;
+        $this->defaultBranch = null;
     }
 
     private function keyMatches(string $key, string $file): bool

src/Subscribers/EnsureTiaAssertionsAreRecordedOnFinished.php

@@ -22,7 +22,7 @@ final readonly class EnsureTiaAssertionsAreRecordedOnFinished implements Finishe
 
         if ($test instanceof TestMethod) {
             $this->collector->recordAssertions(
-                $test->className().'::'.$test->methodName(),
+                $test->id(),
                 $event->numberOfAssertionsPerformed(),
             );
         }

src/Subscribers/EnsureTiaResultIsRecordedOnDeprecationTriggered.php

@@ -0,0 +1,26 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Pest\Subscribers;
+
+use Pest\Plugins\Tia\ResultCollector;
+use PHPUnit\Event\Test\DeprecationTriggered;
+use PHPUnit\Event\Test\DeprecationTriggeredSubscriber;
+
+/**
+ * @internal
+ */
+final readonly class EnsureTiaResultIsRecordedOnDeprecationTriggered implements DeprecationTriggeredSubscriber
+{
+    public function __construct(private ResultCollector $collector) {}
+
+    public function notify(DeprecationTriggered $event): void
+    {
+        if ($event->wasSuppressed()) {
+            return;
+        }
+
+        $this->collector->testTriggeredDeprecation($event->message());
+    }
+}

src/Subscribers/EnsureTiaResultIsRecordedOnNoticeTriggered.php

@@ -0,0 +1,26 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Pest\Subscribers;
+
+use Pest\Plugins\Tia\ResultCollector;
+use PHPUnit\Event\Test\NoticeTriggered;
+use PHPUnit\Event\Test\NoticeTriggeredSubscriber;
+
+/**
+ * @internal
+ */
+final readonly class EnsureTiaResultIsRecordedOnNoticeTriggered implements NoticeTriggeredSubscriber
+{
+    public function __construct(private ResultCollector $collector) {}
+
+    public function notify(NoticeTriggered $event): void
+    {
+        if ($event->wasSuppressed()) {
+            return;
+        }
+
+        $this->collector->testTriggeredNotice($event->message());
+    }
+}

src/Subscribers/EnsureTiaResultIsRecordedOnPhpDeprecationTriggered.php

@@ -0,0 +1,26 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Pest\Subscribers;
+
+use Pest\Plugins\Tia\ResultCollector;
+use PHPUnit\Event\Test\PhpDeprecationTriggered;
+use PHPUnit\Event\Test\PhpDeprecationTriggeredSubscriber;
+
+/**
+ * @internal
+ */
+final readonly class EnsureTiaResultIsRecordedOnPhpDeprecationTriggered implements PhpDeprecationTriggeredSubscriber
+{
+    public function __construct(private ResultCollector $collector) {}
+
+    public function notify(PhpDeprecationTriggered $event): void
+    {
+        if ($event->wasSuppressed()) {
+            return;
+        }
+
+        $this->collector->testTriggeredDeprecation($event->message());
+    }
+}

src/Subscribers/EnsureTiaResultIsRecordedOnPhpNoticeTriggered.php

@@ -0,0 +1,26 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Pest\Subscribers;
+
+use Pest\Plugins\Tia\ResultCollector;
+use PHPUnit\Event\Test\PhpNoticeTriggered;
+use PHPUnit\Event\Test\PhpNoticeTriggeredSubscriber;
+
+/**
+ * @internal
+ */
+final readonly class EnsureTiaResultIsRecordedOnPhpNoticeTriggered implements PhpNoticeTriggeredSubscriber
+{
+    public function __construct(private ResultCollector $collector) {}
+
+    public function notify(PhpNoticeTriggered $event): void
+    {
+        if ($event->wasSuppressed()) {
+            return;
+        }
+
+        $this->collector->testTriggeredNotice($event->message());
+    }
+}

src/Subscribers/EnsureTiaResultIsRecordedOnPhpWarningTriggered.php

@@ -0,0 +1,26 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Pest\Subscribers;
+
+use Pest\Plugins\Tia\ResultCollector;
+use PHPUnit\Event\Test\PhpWarningTriggered;
+use PHPUnit\Event\Test\PhpWarningTriggeredSubscriber;
+
+/**
+ * @internal
+ */
+final readonly class EnsureTiaResultIsRecordedOnPhpWarningTriggered implements PhpWarningTriggeredSubscriber
+{
+    public function __construct(private ResultCollector $collector) {}
+
+    public function notify(PhpWarningTriggered $event): void
+    {
+        if ($event->wasSuppressed()) {
+            return;
+        }
+
+        $this->collector->testTriggeredWarning($event->message());
+    }
+}

src/Subscribers/EnsureTiaResultIsRecordedOnWarningTriggered.php

@@ -0,0 +1,26 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Pest\Subscribers;
+
+use Pest\Plugins\Tia\ResultCollector;
+use PHPUnit\Event\Test\WarningTriggered;
+use PHPUnit\Event\Test\WarningTriggeredSubscriber;
+
+/**
+ * @internal
+ */
+final readonly class EnsureTiaResultIsRecordedOnWarningTriggered implements WarningTriggeredSubscriber
+{
+    public function __construct(private ResultCollector $collector) {}
+
+    public function notify(WarningTriggered $event): void
+    {
+        if ($event->wasSuppressed()) {
+            return;
+        }
+
+        $this->collector->testTriggeredWarning($event->message());
+    }
+}

src/Subscribers/EnsureTiaResultsAreCollected.php

@@ -21,7 +21,7 @@ final readonly class EnsureTiaResultsAreCollected implements PreparationStartedS
         $test = $event->test();
 
         if ($test instanceof TestMethod) {
-            $this->collector->testPrepared($test->className().'::'.$test->methodName(), $test->file());
+            $this->collector->testPrepared($test->id(), $test->file());
         }
     }
 }

src/Support/Git.php

@@ -0,0 +1,116 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Pest\Support;
+
+use Symfony\Component\Process\Process;
+
+/**
+ * @internal
+ */
+final readonly class Git
+{
+    private const float TIMEOUT = 5.0;
+
+    public function __construct(
+        private ?string $directory = null,
+        private float $timeout = self::TIMEOUT,
+    ) {}
+
+    public function withTimeout(float $timeout): self
+    {
+        return new self($this->directory, $timeout);
+    }
+
+    /**
+     * @param  array<int, string>  $arguments
+     */
+    public function raw(array $arguments): ?string
+    {
+        $result = $this->result($arguments);
+
+        return $result['exitCode'] === 0 ? $result['output'] : null;
+    }
+
+    /**
+     * @param  array<int, string>  $arguments
+     */
+    public function output(array $arguments): ?string
+    {
+        $output = $this->raw($arguments);
+
+        if ($output === null) {
+            return null;
+        }
+
+        $output = trim($output);
+
+        return $output === '' ? null : $output;
+    }
+
+    /**
+     * @param  array<int, string>  $arguments
+     */
+    public function succeeds(array $arguments): bool
+    {
+        return $this->result($arguments)['exitCode'] === 0;
+    }
+
+    /**
+     * @param  array<int, string>  $arguments
+     * @return array{exitCode: int, output: string}
+     */
+    public function result(array $arguments, ?string $input = null): array
+    {
+        $process = new Process(['git', ...$arguments], $this->directory);
+        $process->setTimeout($this->timeout);
+
+        if ($input !== null) {
+            $process->setInput($input);
+        }
+
+        $process->run();
+
+        return [
+            'exitCode' => $process->getExitCode() ?? 1,
+            'output' => $process->getOutput(),
+        ];
+    }
+
+    public function isRepository(): bool
+    {
+        return $this->succeeds(['rev-parse', '--git-dir']);
+    }
+
+    public function hasCommits(): bool
+    {
+        return $this->succeeds(['rev-parse', '--verify', '--quiet', 'HEAD']);
+    }
+
+    public function hasRemote(): bool
+    {
+        return $this->output(['remote']) !== null;
+    }
+
+    public function hasRef(string $ref): bool
+    {
+        return $this->output(['rev-parse', '--verify', '--quiet', $ref]) !== null;
+    }
+
+    public function show(string $sha, string $path): ?string
+    {
+        return $this->raw(['show', $sha.':'.$path]);
+    }
+
+    public function subdirectoryPrefix(): ?string
+    {
+        $prefix = $this->output(['rev-parse', '--show-prefix']);
+
+        if ($prefix === null) {
+            return null;
+        }
+
+        return rtrim(str_replace(DIRECTORY_SEPARATOR, '/', $prefix), '/');
+    }
+}

src/Support/Str.php

@@ -17,6 +17,33 @@ final class Str
 
     private const string PREFIX = '__pest_evaluable_';
 
+    /**
+     * The list of names PHP reserves, and therefore refuses, as class names.
+     *
+     * @see https://github.com/php/php-src/blob/master/Zend/zend_compile.c
+     *
+     * @var array<int, string>
+     */
+    private const array RESERVED_CLASS_NAMES = [
+        'array',
+        'bool',
+        'callable',
+        'false',
+        'float',
+        'int',
+        'iterable',
+        'mixed',
+        'never',
+        'null',
+        'object',
+        'parent',
+        'self',
+        'static',
+        'string',
+        'true',
+        'void',
+    ];
+
     /**
      * Create a (unsecure & non-cryptographically safe) random alpha-numeric
      * string value.
@@ -64,6 +91,35 @@ final class Str
         return (string) preg_replace('/[^a-zA-Z0-9_\x80-\xff]/', '_', $code);
     }
 
+    /**
+     * Determine if the given name is a valid PHP identifier, and therefore may
+     * be used as a single namespace name.
+     */
+    public static function isValidIdentifier(string $name): bool
+    {
+        return preg_match('/^[a-zA-Z_\x80-\xff][a-zA-Z0-9_\x80-\xff]*$/', $name) === 1;
+    }
+
+    /**
+     * Determine if the given name may be declared as a class name by an `eval`.
+     */
+    public static function isValidClassName(string $name): bool
+    {
+        if (! self::isValidIdentifier($name)) {
+            return false;
+        }
+
+        if (in_array(strtolower($name), self::RESERVED_CLASS_NAMES, true)) {
+            return false;
+        }
+
+        $tokens = token_get_all(sprintf('<?php %s;', $name));
+
+        // Anything the lexer sees as a keyword, like `list` or `match`, may not
+        // be used as a class name.
+        return is_array($tokens[1] ?? null) && $tokens[1][0] === T_STRING;
+    }
+
     /**
      * Get the portion of a string before the last occurrence of a given value.
      */

src/TestCaseFilters/GitDirtyTestCaseFilter.php

@@ -8,8 +8,8 @@ use Pest\Contracts\TestCaseFilter;
 use Pest\Exceptions\MissingDependency;
 use Pest\Exceptions\NoDirtyTestsFound;
 use Pest\Panic;
+use Pest\Support\Git;
 use Pest\TestSuite;
-use Symfony\Component\Process\Process;
 
 final class GitDirtyTestCaseFilter implements TestCaseFilter
 {
@@ -52,14 +52,13 @@ final class GitDirtyTestCaseFilter implements TestCaseFilter
      */
     private function loadChangedFiles(): void
     {
-        $process = new Process(['git', 'status', '--short', '--', '*.php']);
+        $status = new Git(timeout: 60.0)->raw(['status', '--short', '--', '*.php']);
-        $process->run();
 
-        if (! $process->isSuccessful()) {
+        if ($status === null) {
             throw new MissingDependency('Filter by dirty files', 'git');
         }
 
-        $output = preg_split('/\R+/', $process->getOutput(), flags: PREG_SPLIT_NO_EMPTY);
+        $output = preg_split('/\R+/', $status, flags: PREG_SPLIT_NO_EMPTY);
         assert(is_array($output));
 
         $dirtyFiles = [];

tests/.pest/snapshots/Visual/Help/visual_snapshot_of_help_command_output.snap

@@ -1,5 +1,5 @@
 
-  Pest Testing Framework 5.0.0-beta.1.  
+  Pest Testing Framework 5.0.3.  
 
   USAGE: pest <file> [options]  
 
@@ -168,6 +168,16 @@
   AI OPTIONS:
   --ai ..... Run a code snippet as a fully scaffolded test for AI verification  
 
+  TIA OPTIONS:
+  --tia  Re-run only the tests affected by your changes, replaying the rest from cache  
+  --no-tia ......................... Disable test impact analysis for this run  
+  --tia --fresh .... Discard the recorded dependency graph and record it again  
+  --tia --filtered ............ Narrow the run to the affected test files only  
+  --tia --locally ......... Enable test impact analysis on local machines only  
+  --tia --baselined  Fetch the shared dependency graph recorded by the CI baseline  
+  --tia --refetch ......... Force a fresh fetch of the shared dependency graph  
+  --baseline  Output to standard output the test impact analysis storage directory  
+
   MUTATION TESTING OPTIONS:
   --mutate .... Runs mutation testing, to understand the quality of your tests  
   --mutate --parallel ...................... Runs mutation testing in parallel  

tests/.pest/snapshots/Visual/Version/visual_snapshot_of_help_command_output.snap

@@ -1,3 +1,3 @@
 
-  Pest Testing Framework 5.0.0-beta.1.  
+  Pest Testing Framework 5.0.3.  
 

tests/.snapshots/Failure.php.inc

@@ -1,27 +1,27 @@
-##teamcity[testSuiteStarted name='Tests/tests/Failure' locationHint='pest_qn://tests/.tests/Failure.php' flowId='1234']
+##teamcity[testSuiteStarted name='Tests/Fixtures/Suites/Failure' locationHint='pest_qn://tests/Fixtures/Suites/Failure.php' flowId='1234']
 ##teamcity[testCount count='8' flowId='1234']
-##teamcity[testStarted name='it can fail with comparison' locationHint='pest_qn://tests/.tests/Failure.php::it can fail with comparison' flowId='1234']
+##teamcity[testStarted name='it can fail with comparison' locationHint='pest_qn://tests/Fixtures/Suites/Failure.php::it can fail with comparison' flowId='1234']
-##teamcity[testFailed name='it can fail with comparison' message='Failed asserting that true matches expected false.' details='at tests/.tests/Failure.php:6' type='comparisonFailure' actual='true' expected='false' flowId='1234']
+##teamcity[testFailed name='it can fail with comparison' message='Failed asserting that true matches expected false.' details='at tests/Fixtures/Suites/Failure.php:6' type='comparisonFailure' actual='true' expected='false' flowId='1234']
 ##teamcity[testFinished name='it can fail with comparison' duration='100000' flowId='1234']
-##teamcity[testStarted name='it can be ignored because of no assertions' locationHint='pest_qn://tests/.tests/Failure.php::it can be ignored because of no assertions' flowId='1234']
+##teamcity[testStarted name='it can be ignored because of no assertions' locationHint='pest_qn://tests/Fixtures/Suites/Failure.php::it can be ignored because of no assertions' flowId='1234']
 ##teamcity[testIgnored name='it can be ignored because of no assertions' message='This test did not perform any assertions' details='' flowId='1234']
 ##teamcity[testFinished name='it can be ignored because of no assertions' duration='100000' flowId='1234']
-##teamcity[testStarted name='it can be ignored because it is skipped' locationHint='pest_qn://tests/.tests/Failure.php::it can be ignored because it is skipped' flowId='1234']
+##teamcity[testStarted name='it can be ignored because it is skipped' locationHint='pest_qn://tests/Fixtures/Suites/Failure.php::it can be ignored because it is skipped' flowId='1234']
 ##teamcity[testIgnored name='it can be ignored because it is skipped' message='This test was ignored.' details='' flowId='1234']
 ##teamcity[testFinished name='it can be ignored because it is skipped' duration='100000' flowId='1234']
-##teamcity[testStarted name='it can fail' locationHint='pest_qn://tests/.tests/Failure.php::it can fail' flowId='1234']
+##teamcity[testStarted name='it can fail' locationHint='pest_qn://tests/Fixtures/Suites/Failure.php::it can fail' flowId='1234']
-##teamcity[testFailed name='it can fail' message='oh noo' details='at tests/.tests/Failure.php:18' flowId='1234']
+##teamcity[testFailed name='it can fail' message='oh noo' details='at tests/Fixtures/Suites/Failure.php:18' flowId='1234']
 ##teamcity[testFinished name='it can fail' duration='100000' flowId='1234']
-##teamcity[testStarted name='it throws exception' locationHint='pest_qn://tests/.tests/Failure.php::it throws exception' flowId='1234']
+##teamcity[testStarted name='it throws exception' locationHint='pest_qn://tests/Fixtures/Suites/Failure.php::it throws exception' flowId='1234']
-##teamcity[testFailed name='it throws exception' message='Exception: test error' details='at tests/.tests/Failure.php:22' flowId='1234']
+##teamcity[testFailed name='it throws exception' message='Exception: test error' details='at tests/Fixtures/Suites/Failure.php:22' flowId='1234']
 ##teamcity[testFinished name='it throws exception' duration='100000' flowId='1234']
-##teamcity[testStarted name='it is not done yet' locationHint='pest_qn://tests/.tests/Failure.php::it is not done yet' flowId='1234']
+##teamcity[testStarted name='it is not done yet' locationHint='pest_qn://tests/Fixtures/Suites/Failure.php::it is not done yet' flowId='1234']
 ##teamcity[testFinished name='it is not done yet' duration='100000' flowId='1234']
-##teamcity[testStarted name='build this one.' locationHint='pest_qn://tests/.tests/Failure.php::build this one.' flowId='1234']
+##teamcity[testStarted name='build this one.' locationHint='pest_qn://tests/Fixtures/Suites/Failure.php::build this one.' flowId='1234']
 ##teamcity[testFinished name='build this one.' duration='100000' flowId='1234']
-##teamcity[testStarted name='it is passing' locationHint='pest_qn://tests/.tests/Failure.php::it is passing' flowId='1234']
+##teamcity[testStarted name='it is passing' locationHint='pest_qn://tests/Fixtures/Suites/Failure.php::it is passing' flowId='1234']
 ##teamcity[testFinished name='it is passing' duration='100000' flowId='1234']
-##teamcity[testSuiteFinished name='Tests/tests/Failure' flowId='1234']
+##teamcity[testSuiteFinished name='Tests/Fixtures/Suites/Failure' flowId='1234']
 
   Tests:    3 failed, 1 risky, 2 todos, 1 skipped, 1 passed (3 assertions)
   Duration: 1.00s

tests/.snapshots/SuccessOnly.php.inc

@@ -1,18 +1,18 @@
-##teamcity[testSuiteStarted name='Tests/tests/SuccessOnly' locationHint='pest_qn://tests/.tests/SuccessOnly.php' flowId='1234']
+##teamcity[testSuiteStarted name='Tests/Fixtures/Suites/SuccessOnly' locationHint='pest_qn://tests/Fixtures/Suites/SuccessOnly.php' flowId='1234']
 ##teamcity[testCount count='4' flowId='1234']
-##teamcity[testStarted name='it can pass with comparison' locationHint='pest_qn://tests/.tests/SuccessOnly.php::it can pass with comparison' flowId='1234']
+##teamcity[testStarted name='it can pass with comparison' locationHint='pest_qn://tests/Fixtures/Suites/SuccessOnly.php::it can pass with comparison' flowId='1234']
 ##teamcity[testFinished name='it can pass with comparison' duration='100000' flowId='1234']
-##teamcity[testStarted name='can also pass' locationHint='pest_qn://tests/.tests/SuccessOnly.php::can also pass' flowId='1234']
+##teamcity[testStarted name='can also pass' locationHint='pest_qn://tests/Fixtures/Suites/SuccessOnly.php::can also pass' flowId='1234']
 ##teamcity[testFinished name='can also pass' duration='100000' flowId='1234']
-##teamcity[testSuiteStarted name='can pass with dataset' locationHint='pest_qn://tests/.tests/SuccessOnly.php::can pass with dataset' flowId='1234']
+##teamcity[testSuiteStarted name='can pass with dataset' locationHint='pest_qn://tests/Fixtures/Suites/SuccessOnly.php::can pass with dataset' flowId='1234']
-##teamcity[testStarted name='can pass with dataset with data set "(true)"' locationHint='pest_qn://tests/.tests/SuccessOnly.php::can pass with dataset with data set "(true)"' flowId='1234']
+##teamcity[testStarted name='can pass with dataset with data set "(true)"' locationHint='pest_qn://tests/Fixtures/Suites/SuccessOnly.php::can pass with dataset with data set "(true)"' flowId='1234']
 ##teamcity[testFinished name='can pass with dataset with data set "(true)"' duration='100000' flowId='1234']
 ##teamcity[testSuiteFinished name='can pass with dataset' flowId='1234']
-##teamcity[testSuiteStarted name='`block` → can pass with dataset in describe block' locationHint='pest_qn://tests/.tests/SuccessOnly.php::`block` → can pass with dataset in describe block' flowId='1234']
+##teamcity[testSuiteStarted name='`block` → can pass with dataset in describe block' locationHint='pest_qn://tests/Fixtures/Suites/SuccessOnly.php::`block` → can pass with dataset in describe block' flowId='1234']
-##teamcity[testStarted name='`block` → can pass with dataset in describe block with data set "(1)"' locationHint='pest_qn://tests/.tests/SuccessOnly.php::`block` → can pass with dataset in describe block with data set "(1)"' flowId='1234']
+##teamcity[testStarted name='`block` → can pass with dataset in describe block with data set "(1)"' locationHint='pest_qn://tests/Fixtures/Suites/SuccessOnly.php::`block` → can pass with dataset in describe block with data set "(1)"' flowId='1234']
 ##teamcity[testFinished name='`block` → can pass with dataset in describe block with data set "(1)"' duration='100000' flowId='1234']
 ##teamcity[testSuiteFinished name='`block` → can pass with dataset in describe block' flowId='1234']
-##teamcity[testSuiteFinished name='Tests/tests/SuccessOnly' flowId='1234']
+##teamcity[testSuiteFinished name='Tests/Fixtures/Suites/SuccessOnly' flowId='1234']
 
   Tests:    4 passed (4 assertions)
   Duration: 1.00s

tests/.snapshots/allows-to-run-a-directory.txt

@@ -1,17 +1,4 @@
-   WARN  Tests\Fixtures\CollisionTest
-  - error
-  - success
-
    PASS  Tests\Fixtures\DirectoryWithTests\ExampleTest
   ✓ it example 1
 
-   PASS  Tests\Fixtures\ExampleTest
+  Tests:    1 passed (1 assertions)
-  ✓ it example 2
-
-   WARN  Tests\Fixtures\Inheritance\Base\ExampleTest
-  - example
-
-   PASS  Tests\Fixtures\Inheritance\ExampleTest
-  ✓ example
-
-  Tests:    3 skipped, 3 passed (3 assertions)

tests/.snapshots/success.txt

@@ -1565,6 +1565,229 @@
   ✓ it allows performing no expectations without being risky
   ✓ a "describe" group of tests → it allows performing no expectations without being risky
 
+   PASS  Tests\Features\Tia
+  ✓ it does not run user hooks when replaying cached skipped and incomplete results
+
+   PASS  Tests\Features\Tia\BranchShapes
+  ✓ a branch name git allows is a branch key TIA can hold with dataset "slashes"
+  ✓ a branch name git allows is a branch key TIA can hold with dataset "dots"
+  ✓ a branch name git allows is a branch key TIA can hold with dataset "unicode"
+  ✓ a branch name git allows is a branch key TIA can hold with dataset "digits"
+  ✓ a branch name git allows is a branch key TIA can hold with dataset "underscores"
+  ✓ a branch name git allows is a branch key TIA can hold with dataset "very long"
+  ✓ a branch differing from the default only in case gets its own key
+  ✓ a branch that only lives on the remote keeps its baseline
+  ✓ a branch checked out in a worktree keeps its baseline
+  ✓ deleting many branches reclaims every one of their baselines with dataset "sequential"
+  ✓ deleting many branches reclaims every one of their baselines with dataset "parallel"
+  ✓ a narrowed run does not reclaim anything
+  ✓ a detached HEAD does not reclaim anything either
+  ✓ the default branch baseline survives every branch that comes and goes
+  ✓ a project below the git repository root refuses to run and writes nothing with dataset "sequential"
+  ✓ a project below the git repository root refuses to run and writes nothing with dataset "parallel"
+  ✓ a repository with no commits says so, and leaves plain runs alone
+  ✓ a directory with no repository at all still asks for git
+
+   PASS  Tests\Features\Tia\CompleteRunWriteTier
+  ✓ a complete run prunes a deleted test with dataset "sequential"
+  ✓ a complete run prunes a deleted test with dataset "parallel"
+  ✓ a complete run records nothing for a test file the graph does not know
+  ✓ a partial run records nothing for a test file the graph does not know
+  ✓ a truncated run does not prune with dataset "sequential"
+  ✓ a truncated run does not prune with dataset "parallel"
+  ✓ a green bail run is complete
+  ✓ --no-tia refreshes results without enabling tia with dataset "sequential"
+  ✓ --no-tia refreshes results without enabling tia with dataset "parallel"
+  ✓ a plain run refreshes the results it executed with dataset "sequential"
+  ✓ a plain run refreshes the results it executed with dataset "parallel"
+  ✓ a parallel replay keeps the recorded time of tests that did not run
+  ✓ a run that never enables tia creates no graph with dataset "plain"
+  ✓ a run that never enables tia creates no graph with dataset "filtered"
+  ✓ a run that never enables tia creates no graph with dataset "parallel filtered"
+  ✓ a test edit narrows to the affected file and replays the rest
+  ✓ a parallel run merges worker results into the parent baseline
+
+   PASS  Tests\Features\Tia\CoveragePiggyback
+  ✓ a coverage report does not found a dependency graph with dataset "pest coverage"
+  ✓ a coverage report does not found a dependency graph with dataset "phpunit coverage report"
+  ✓ a coverage report does not found a dependency graph with dataset "parallel"
+  ✓ a plain run after a coverage run records the whole project scope
+  ✓ a coverage report leaves the edges of an existing graph alone
+
+   PASS  Tests\Features\Tia\DefaultBranchReplay
+  ✓ replays the default branch baseline on a new branch
+  ✓ replays whatever the default branch is called with ('main')
+  ✓ replays whatever the default branch is called with ('master')
+  ✓ replays whatever the default branch is called with ('trunk')
+  ✓ replays whatever the default branch is called with ('develop')
+  ✓ replays on a second new branch too
+  ✓ writes nothing on a second run on the same branch
+  ✓ replays on a branch whose name contains slashes
+  ✓ replays again once back on the default branch
+  ✓ replays on a new branch when tia is enabled by configuration
+  ✓ a narrowed run on a new branch does not cost the fallback with dataset "sequential"
+  ✓ a narrowed run on a new branch does not cost the fallback with dataset "parallel"
+  ✓ replays inside a worktree on a new branch
+
+   PASS  Tests\Features\Tia\DefaultBranchResolution
+  ✓ a declared default branch beats autodetection
+  ✓ a declared default branch that does not exist degrades to a full run
+  ✓ a renamed default branch replays and writes under its new name
+  ✓ the CI provider names the default branch where the checkout cannot
+  ✓ GitLab names the default branch through its own variable
+  ✓ a lone recorded baseline names the default branch
+  ✓ a default branch nothing can name is refused rather than guessed
+  ✓ an init.defaultBranch naming a branch that exists is still trusted
+  ✓ a repository with no remote is refused rather than silently re-run
+  ✓ a remote-less repository holding one baseline is not refused
+  ✓ a declared default branch stands in for a missing remote
+  ✓ tia still requires git
+  ✓ a plain run outside a repository creates no baseline
+  ✓ the default branch is resolved once per run, not once per test
+
+   PASS  Tests\Features\Tia\DefaultBranchWriteTier
+  ✓ narrows to the affected tests on a new branch
+  ✓ filtered mode reads the fallback too
+  ✓ filtered mode finds nothing to do on a clean green feature branch
+  ✓ filtered mode falls back to a full replay when a cached failure cannot be located
+  ✓ filtered mode finds nothing to do on the default branch itself
+  ✓ a detached HEAD replays without minting a branch key
+  ✓ a detached HEAD does not write into the default branch baseline with dataset "sequential"
+  ✓ a detached HEAD does not write into the default branch baseline with dataset "parallel"
+  ✓ the branch that ran gets its own key and the default branch keeps its baseline
+  ✓ the fallback reaches parallel workers
+
+   PASS  Tests\Features\Tia\FilteredMode
+  ✓ re-runs a cached failure on a clean tree
+  ✓ an explicit path turns filtered mode off
+  ✓ filtered mode runs the whole suite when there is no baseline
+  ✓ filtered mode finds nothing to do in parallel either
+  ✓ a corrupt graph is reported and does not crash the run
+  ✓ --parallel --retry is refused and leaves the graph alone
+
+   PASS  Tests\Features\Tia\HostileState
+  ✓ a graph mangled beyond use still lets the suite run with dataset "empty"
+  ✓ a graph mangled beyond use still lets the suite run with dataset "truncated"
+  ✓ a graph mangled beyond use still lets the suite run with dataset "not json"
+  ✓ a graph mangled beyond use still lets the suite run with dataset "json scalar"
+  ✓ a graph mangled beyond use still lets the suite run with dataset "json list"
+  ✓ a graph mangled beyond use still lets the suite run with dataset "json null"
+  ✓ a graph mangled beyond use still lets the suite run with dataset "empty object"
+  ✓ a graph mangled beyond use still lets the suite run with dataset "nul bytes"
+  ✓ a graph whose shape is wrong everywhere is repaired rather than trusted with dataset "sequential"
+  ✓ a graph whose shape is wrong everywhere is repaired rather than trusted with dataset "parallel"
+  ✓ a cached status this build cannot interpret is re-run, not replayed with dataset "below the range"
+  ✓ a cached status this build cannot interpret is re-run, not replayed with dataset "one past the range"
+  ✓ a cached status this build cannot interpret is re-run, not replayed with dataset "far past the range"
+  ✓ a cached status this build cannot interpret is re-run, not replayed with dataset "huge"
+  ✓ a cached status with no replay of its own does not fail the run with dataset "notice"
+  ✓ a cached status with no replay of its own does not fail the run with dataset "deprecation"
+  ✓ a cached status with no replay of its own does not fail the run with dataset "warning"
+  ✓ a cached skip or todo replays with its message intact with dataset "skipped"
+  ✓ a cached skip or todo replays with its message intact with dataset "incomplete"
+  ✓ a cached failure with a multi-line message re-runs rather than replaying the text
+  ✓ a result pointing outside the project is not addressable and widens the run
+  ✓ an edge pointing at a file id that does not exist is ignored
+  ✓ a graph from a schema this build does not know is rebuilt, not read
+  ✓ graph.json being a directory does not stop the run
+  ✓ a state dir it cannot write to still replays
+
+   PASS  Tests\Features\Tia\IssueStatuses
+  ✓ a triggered issue is recorded as itself, not as a pass with dataset "sequential" / dataset "deprecation"
+  ✓ a triggered issue is recorded as itself, not as a pass with dataset "sequential" / dataset "notice"
+  ✓ a triggered issue is recorded as itself, not as a pass with dataset "sequential" / dataset "warning"
+  ✓ a triggered issue is recorded as itself, not as a pass with dataset "parallel" / dataset "deprecation"
+  ✓ a triggered issue is recorded as itself, not as a pass with dataset "parallel" / dataset "notice"
+  ✓ a triggered issue is recorded as itself, not as a pass with dataset "parallel" / dataset "warning"
+  ✓ a cached deprecation still fails the run that asked to fail on one with dataset "sequential"
+  ✓ a cached deprecation still fails the run that asked to fail on one with dataset "parallel"
+  ✓ replaying a cached issue does not downgrade it to a pass with dataset "sequential"
+  ✓ replaying a cached issue does not downgrade it to a pass with dataset "parallel"
+  ✓ a failure outranks an issue triggered on the way to it
+  ✓ a skip outranks an issue triggered on the way to it
+  ✓ a suppressed issue is not recorded
+
+   PASS  Tests\Features\Tia\PartialRunWriteTier
+  ✓ a filtered run rewrites only the test that ran
+  ✓ a filtered run under --tia announces that tia does not apply
+  ✓ a test suffix narrows the tier even though every test runs
+  ✓ a dirty run narrows to the uncommitted test edit
+  ✓ filtered mode yields to an explicit filter
+  ✓ an env flag narrows exactly like the option it mirrors with ('PEST_TIA')
+  ✓ an env flag narrows exactly like the option it mirrors with ('PEST_TIA_FILTERED')
+  ✓ a partial run does not purge the graph even with --fresh
+  ✓ --no-tia does not stop a partial run from refreshing its own entry
+  ✓ two partial runs each keep the other entry
+  ✓ a shard is a partial run
+  ✓ a parallel partial run records the test that ran, like a sequential one
+
+   PASS  Tests\Features\Tia\RemoteBaseline
+  ✓ a published baseline is fetched instead of recorded locally
+  ✓ a fetched baseline that will not decode is discarded rather than trusted
+  ✓ a fetched baseline recorded against another tree is not used
+  ✓ an artifact without a graph in it fails loudly
+  ✓ a baseline that cannot be authenticated for fails loudly
+  ✓ a workflow or artifact that is not there fails loudly
+  ✓ a network failure warns and lets the suite run with dataset "querying the runs"
+  ✓ a network failure warns and lets the suite run with dataset "downloading the artifact"
+  ✓ no published baseline yet starts a cooldown, and a corrupt cooldown does not break the run
+
+   PASS  Tests\Features\Tia\SelectionPaths
+  ✓ a committed rename selects the tests that depended on the old path with dataset "sequential"
+  ✓ a committed rename selects the tests that depended on the old path with dataset "parallel"
+  ✓ an affected test file that is gone does not strand a filtered run with dataset "sequential"
+  ✓ an affected test file that is gone does not strand a filtered run with dataset "parallel"
+  ✓ a plain run reclaims the edge of a test file that is gone
+  ✓ a changed view selects the test that rendered it
+  ✓ a changed partial selects the test that rendered its ancestor with dataset "direct @include"
+  ✓ a changed partial selects the test that rendered its ancestor with dataset "transitive @include"
+  ✓ a changed partial selects the test that rendered its ancestor with dataset "x- component"
+  ✓ a changed partial selects the test that rendered its ancestor with dataset "include cycle"
+  ✓ a changed Inertia page selects the test that rendered its component
+  ✓ a changed shared JS module selects the tests of the pages that import it
+  ✓ a changed frontend runtime file selects every Inertia test
+
+   PASS  Tests\Features\Tia\StateReclamation
+  ✓ a detached HEAD does not purge the graph on structural drift with dataset "sequential"
+  ✓ a detached HEAD does not purge the graph on structural drift with dataset "parallel"
+  ✓ a detached HEAD does not purge the graph with --fresh either with dataset "sequential"
+  ✓ a detached HEAD does not purge the graph with --fresh either with dataset "parallel"
+  ✓ a detached HEAD leaves an unreadable graph for a checkout that can rebuild it
+  ✓ a cached failure whose test file was deleted stops widening later runs with dataset "sequential"
+  ✓ a cached failure whose test file was deleted stops widening later runs with dataset "parallel"
+  ✓ a complete run reclaims the entry and the edge of a deleted test file with dataset "sequential"
+  ✓ a complete run reclaims the entry and the edge of a deleted test file with dataset "parallel"
+  ✓ a pruned result does not come back from the fallback with dataset "sequential"
+  ✓ a pruned result does not come back from the fallback with dataset "parallel"
+  ✓ the fallback still reaches a branch that has never run a test file
+  ✓ a branch that git no longer knows loses its baseline
+  ✓ an unknown cached status is re-run rather than replayed as a failure with dataset "unknown"
+  ✓ an unknown cached status is re-run rather than replayed as a failure with dataset "future"
+  ✓ an unknown cached status is re-run rather than replayed as a failure with dataset "garbage"
+  ✓ a cached notice, deprecation or warning does not replay as a failure with dataset "notice"
+  ✓ a cached notice, deprecation or warning does not replay as a failure with dataset "deprecation"
+  ✓ a cached notice, deprecation or warning does not replay as a failure with dataset "warning"
+  ✓ a malformed baseline entry cannot break the run with dataset "sequential"
+  ✓ a malformed baseline entry cannot break the run with dataset "parallel"
+  ✓ a run torn down mid-file does not prune the tests it never reached with dataset "sequential"
+  ✓ a run torn down mid-file does not prune the tests it never reached with dataset "parallel"
+  ✓ a fatal error mid-file is a test error, not a truncation with dataset "sequential"
+  ✓ a fatal error mid-file is a test error, not a truncation with dataset "parallel"
+  ✓ a green complete run leaves the graph exactly as it found it with dataset "bail"
+  ✓ a green complete run leaves the graph exactly as it found it with dataset "stop-on-failure"
+  ✓ a green complete run leaves the graph exactly as it found it with dataset "compact"
+  ✓ a green complete run leaves the graph exactly as it found it with dataset "parallel bail"
+  ✓ a green complete run leaves the graph exactly as it found it with dataset "parallel one process"
+  ✓ a green complete run leaves the graph exactly as it found it with dataset "parallel more processes than files"
+  ✓ --tia --no-tia is a plain run that still refreshes what it executed with dataset "sequential"
+  ✓ --tia --no-tia is a plain run that still refreshes what it executed with dataset "parallel"
+  ✓ --fresh on a partial run neither purges nor prunes with dataset "sequential"
+  ✓ --fresh on a partial run neither purges nor prunes with dataset "parallel"
+  ✓ a second green run on a feature branch writes nothing at all with dataset "sequential"
+  ✓ a second green run on a feature branch writes nothing at all with dataset "parallel"
+  ✓ a graph whose recorded commit is gone is re-anchored, not warned about forever with dataset "sequential"
+  ✓ a graph whose recorded commit is gone is re-anchored, not warned about forever with dataset "parallel"
+
    PASS  Tests\Features\Ticket
   ✓ it may be associated with an ticket #1, #2
   ✓ nested → it may be associated with an ticket #1, #4, #5, #6, #3
@@ -1908,6 +2131,11 @@
   ✓ activateLinkTracking() → it tracks linked sources across consecutive tests
   ✓ activateLinkTracking() → it records nothing while inactive
 
+   PASS  Tests\Unit\Plugins\Tia\ResultKey
+  ✓ it keys a result per dataset row rather than per method
+  ✓ it records assertions against the same per-dataset key
+  ✓ it leaves a test without a dataset keyed by class and method
+
    PASS  Tests\Unit\Plugins\Tia\TableExtractor
   ✓ fromSql() → it extracts tables from plain DML
   ✓ fromSql() → it extracts tables from joins
@@ -1916,10 +2144,12 @@
   ✓ fromSql() → it records the table, not the schema, for qualified identifiers
   ✓ fromSql() → it handles quoted identifiers
   ✓ fromSql() → it ignores schema metadata tables
+  ✓ fromSql() → it does not leak int keys for numeric identifiers
   ✓ fromSql() → it returns nothing for non-DML statements
   ✓ fromMigrationSource() → it extracts tables from Schema builder calls
   ✓ fromMigrationSource() → it extracts tables from raw DDL statements
   ✓ fromMigrationSource() → it records the table, not the schema, in qualified DDL and DML
+  ✓ fromMigrationSource() → it does not leak int keys for numeric table names
   ✓ fromMigrationSource() → it extracts tables from DB::table calls
 
    PASS  Tests\Unit\Plugins\Tia\TestPaths
@@ -2153,6 +2383,7 @@
   ✓ a parallel test can extend another test with same name
   ✓ parallel reports invalid datasets as failures
   ✓ parallel can have multiple exclude-groups
+  ✓ parallel can have multiple groups
 
    PASS  Tests\Visual\ParallelNestedDatasets
   ✓ parallel loads nested datasets from nested directories
@@ -2186,4 +2417,4 @@
   ✓ pass with dataset with ('my-datas-set-value')
   ✓ within describe → pass with dataset with ('my-datas-set-value')
 
-  Tests:    1 deprecated, 4 warnings, 5 incomplete, 2 notices, 40 todos, 35 skipped, 1542 passed (3375 assertions)
+  Tests:    1 deprecated, 4 warnings, 5 incomplete, 2 notices, 40 todos, 35 skipped, 1743 passed (3953 assertions)

tests/Features/DatasetProviderErrors.php

@@ -18,27 +18,27 @@ $run = function (string $target): array {
 };
 
 test('reports missing datasets as errors for a single file run', function () use ($run): void {
-    $result = $run('tests/.tests/IssueOnly.php');
+    $result = $run('tests/Fixtures/Suites/IssueOnly.php');
 
     expect($result['output'])
-        ->toContain("A dataset with the name `missing` does not exist. You can create it using `dataset('missing', ['a', 'b']);`.")
+        ->toContain("A dataset with the name [missing] does not exist. You can create it using `dataset('missing', ['a', 'b']);`.")
         ->toContain('FAILED')
         ->toContain('Tests:    1 failed')
         ->and($result['code'])->not->toBe(0);
 })->skipOnWindows();
 
 test('reports missing datasets as errors alongside passing tests', function () use ($run): void {
-    $result = $run('tests/.tests/IssueWithPassing.php');
+    $result = $run('tests/Fixtures/Suites/IssueWithPassing.php');
 
     expect($result['output'])
-        ->toContain("A dataset with the name `missing` does not exist. You can create it using `dataset('missing', ['a', 'b']);`.")
+        ->toContain("A dataset with the name [missing] does not exist. You can create it using `dataset('missing', ['a', 'b']);`.")
         ->toContain('1 passed')
         ->toContain('1 failed')
         ->and($result['code'])->not->toBe(0);
 })->skipOnWindows();
 
 test('reports dataset closure exceptions as errors', function () use ($run): void {
-    $result = $run('tests/.tests/DatasetClosureThrows.php');
+    $result = $run('tests/Fixtures/Suites/DatasetClosureThrows.php');
 
     expect($result['output'])
         ->toContain('boom from dataset')

tests/Features/DatasetsTests.php

@@ -10,12 +10,12 @@ beforeEach(function (): void {
 });
 
 it('throws exception if dataset does not exist', function (): void {
-    expect(fn () => DatasetsRepository::resolve(['first'], __FILE__))->toThrow(DatasetDoesNotExist::class, "A dataset with the name `first` does not exist. You can create it using `dataset('first', ['a', 'b']);`.");
+    expect(fn () => DatasetsRepository::resolve(['first'], __FILE__))->toThrow(DatasetDoesNotExist::class, "A dataset with the name [first] does not exist. You can create it using `dataset('first', ['a', 'b']);`.");
 });
 
 it('throws exception if dataset already exist', function (): void {
     DatasetsRepository::set('second', [[]], __DIR__);
-    expect(fn () => DatasetsRepository::set('second', [[]], __DIR__))->toThrow(DatasetAlreadyExists::class, 'A dataset with the name `second` already exists in scope ['.__DIR__.'].');
+    expect(fn () => DatasetsRepository::set('second', [[]], __DIR__))->toThrow(DatasetAlreadyExists::class, 'A dataset with the name [second] already exists in scope ['.__DIR__.'].');
 });
 
 it('sets closures', function (): void {

tests/Features/Expect/pipes.php

@@ -38,7 +38,7 @@ class State
 {
     public array $runCount = [];
 
-    public array $appliedCount = [];
+    public array $appliedCount;
 
     public function __construct()
     {

tests/Features/Flaky.php

@@ -142,7 +142,7 @@ it('works as higher order test')
 
 it('fails after exhausting all retries', function (): void {
     $process = new Process(
-        ['php', 'bin/pest', 'tests/.tests/FlakyFailure.php'],
+        ['php', 'bin/pest', 'tests/Fixtures/Suites/FlakyFailure.php'],
         dirname(__DIR__, 2),
         ['COLLISION_PRINTER' => 'DefaultPrinter', 'COLLISION_IGNORE_DURATION' => 'true', 'PAO_DISABLE' => '1'],
     );

tests/Features/Tia.php

@@ -0,0 +1,84 @@
+<?php
+
+use Pest\Plugins\Tia;
+use Pest\Plugins\Tia\ChangedFiles;
+use Pest\Plugins\Tia\FileState;
+use Pest\Plugins\Tia\Fingerprint;
+use Pest\Plugins\Tia\Graph;
+use Pest\Plugins\Tia\Storage;
+use Pest\Support\Str;
+use Symfony\Component\Process\Process;
+
+it('does not run user hooks when replaying cached skipped and incomplete results', function (): void {
+    $projectRoot = dirname(__DIR__, 2);
+    $home = sys_get_temp_dir().'/pest-tia-'.bin2hex(random_bytes(8));
+    $fixture = 'tests/Fixtures/Suites/TiaReplayHooks.php';
+
+    mkdir($home, 0755, true);
+
+    try {
+        $changedFiles = new ChangedFiles($projectRoot);
+        $branch = $changedFiles->currentBranch() ?? 'main';
+        $sha = $changedFiles->currentSha();
+
+        $id = fn (string $description): string => 'P\Tests\Fixtures\Suites\TiaReplayHooks::'.Str::evaluable($description);
+
+        $graph = new Graph($projectRoot);
+        $graph->setFingerprint(Fingerprint::compute($projectRoot));
+        $graph->setRecordedAtSha($branch, $sha);
+        // Hashes the working tree as it stands, so the replay sees nothing as changed.
+        $graph->setLastRunTree($branch, $changedFiles->snapshotTree($changedFiles->since($sha) ?? []));
+        $graph->markKnownTestFiles([$fixture]);
+        $graph->setResult($branch, $id('replayed pass'), 0, '', 0.01, 1, $fixture);
+        $graph->setResult($branch, $id('replayed skip'), 1, 'cached skip', 0.01, 0, $fixture);
+        $graph->setResult($branch, $id('replayed incomplete'), 2, 'cached incomplete', 0.01, 0, $fixture);
+
+        $json = $graph->encode();
+
+        expect($json)->not->toBeNull();
+
+        $originalHome = getenv('HOME');
+        putenv('HOME='.$home);
+
+        try {
+            $storage = new FileState(Storage::tempDir($projectRoot));
+        } finally {
+            putenv($originalHome === false ? 'HOME' : 'HOME='.$originalHome);
+        }
+
+        expect($storage->write(Tia::KEY_GRAPH, (string) $json))->toBeTrue();
+
+        $process = new Process(
+            ['php', 'bin/pest', '--configuration', 'tests/Fixtures/Suites/TiaReplayHooks.xml', '--tia'],
+            $projectRoot,
+            [
+                'COLLISION_PRINTER' => 'DefaultPrinter',
+                'COLLISION_IGNORE_DURATION' => 'true',
+                'PARATEST' => 0,
+                'PAO_DISABLE' => '1',
+                'HOME' => $home,
+            ],
+        );
+
+        $process->run();
+
+        $output = removeAnsiEscapeSequences($process->getOutput().$process->getErrorOutput());
+
+        // Both hooks throw, so the run stays green only if neither one ran.
+        expect($output)->toContain('3 replayed')
+            ->and($output)->not->toContain('must not run for replayed tests')
+            ->and($output)->toContain('1 incomplete, 1 skipped, 1 passed')
+            ->and($process->getExitCode())->toBe(0);
+    } finally {
+        $paths = new RecursiveIteratorIterator(
+            new RecursiveDirectoryIterator($home, FilesystemIterator::SKIP_DOTS),
+            RecursiveIteratorIterator::CHILD_FIRST,
+        );
+
+        foreach ($paths as $path) {
+            $path->isDir() ? @rmdir($path->getPathname()) : @unlink($path->getPathname());
+        }
+
+        @rmdir($home);
+    }
+})->skipOnWindows();

tests/Features/Tia/BranchShapes.php

@@ -0,0 +1,197 @@
+<?php
+
+declare(strict_types=1);
+
+use Tests\Fixtures\Tia\Project;
+
+afterEach(function (): void {
+    Project::destroyAll();
+});
+
+test('a branch name git allows is a branch key TIA can hold', function (string $branch): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->git()->switchTo($branch, new: true);
+
+    $result = $project->pest('--tia');
+    $delta = $project->delta();
+
+    expect($result->replayed())->toBe(Project::TOTAL_TESTS, $result->describe())
+        ->and($result->uncached())->toBe(0, $result->describe())
+        ->and($project->branchKeys())->toBe(['master', $branch])
+        ->and($delta->baselineUntouched('master'))->toBeTrue($delta->summary());
+})->with([
+    'slashes' => 'feature/deep/nesting',
+    'dots' => 'release.1.2.x',
+    'unicode' => 'feature-café-日本',
+    'digits' => '12345',
+    'underscores' => 'feature_x_y',
+    'very long' => 'feature-'.str_repeat('x', 180),
+])->skipOnWindows();
+
+test('a branch differing from the default only in case gets its own key', function (): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->git()->switchTo('MASTER-2', new: true);
+
+    $result = $project->pest('--tia');
+
+    expect($result->replayed())->toBe(Project::TOTAL_TESTS, $result->describe())
+        ->and($project->branchKeys())->toBe(['master', 'MASTER-2']);
+})->skipOnWindows();
+
+test('a branch that only lives on the remote keeps its baseline', function (): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->git()->switchTo('remote-only', new: true);
+    $project->pest('--tia');
+
+    $project->git()->switchTo('master');
+    $project->git()->run(['update-ref', 'refs/remotes/origin/remote-only', 'HEAD']);
+    $project->git()->run(['branch', '-D', 'remote-only']);
+
+    $project->pest('--tia');
+
+    expect($project->branchKeys())->toBe(['master', 'remote-only']);
+})->skipOnWindows();
+
+test('a branch checked out in a worktree keeps its baseline', function (): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->git()->switchTo('wt-branch', new: true);
+    $project->pest('--tia');
+
+    $project->git()->switchTo('master');
+    $project->git()->run(['worktree', 'add', '--quiet', $project->path().'-wt', 'wt-branch']);
+
+    $project->pest('--tia');
+
+    $project->git()->run(['worktree', 'remove', '--force', $project->path().'-wt']);
+
+    expect($project->branchKeys())->toBe(['master', 'wt-branch']);
+})->skipOnWindows();
+
+test('deleting many branches reclaims every one of their baselines', function (array $arguments): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    foreach (range(1, 4) as $index) {
+        $project->git()->switchTo('feature-'.$index, new: true);
+        $project->pest('--tia', ...$arguments);
+    }
+
+    expect($project->branchKeys())->toHaveCount(5);
+
+    $project->git()->switchTo('master');
+
+    foreach (range(1, 4) as $index) {
+        $project->git()->run(['branch', '-D', 'feature-'.$index]);
+    }
+
+    $project->pest('--tia', ...$arguments);
+
+    expect($project->branchKeys())->toBe(['master']);
+})->with(Project::SEQUENTIAL_AND_PARALLEL)->skipOnWindows();
+
+test('a narrowed run does not reclaim anything', function (): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->git()->switchTo('feature-x', new: true);
+    $project->pest('--tia');
+
+    $project->git()->switchTo('master');
+    $project->git()->run(['branch', '-D', 'feature-x']);
+
+    $project->snapshot();
+    $project->pest('--tia', '--filter=adds two numbers');
+    $delta = $project->delta();
+
+    expect($project->branchKeys())->toBe(['master', 'feature-x'])
+        ->and($delta->isResultsOnly())->toBeTrue($delta->summary());
+})->skipOnWindows();
+
+test('a detached HEAD does not reclaim anything either', function (): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->git()->switchTo('feature-x', new: true);
+    $project->pest('--tia');
+
+    $project->git()->switchTo('master');
+    $project->git()->run(['branch', '-D', 'feature-x']);
+    $project->git()->detach();
+
+    $project->snapshot();
+    $project->pest('--tia');
+    $delta = $project->delta();
+
+    expect($project->branchKeys())->toBe(['master', 'feature-x'])
+        ->and($delta->isHardSuppressed())->toBeTrue($delta->summary());
+})->skipOnWindows();
+
+test('the default branch baseline survives every branch that comes and goes', function (): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->git()->switchTo('feature-x', new: true);
+    $project->pest('--tia');
+
+    $project->git()->switchTo('master');
+    $project->git()->run(['branch', '-D', 'feature-x']);
+
+    $project->snapshot();
+    $result = $project->pest('--tia');
+    $delta = $project->delta();
+
+    expect($result->replayed())->toBe(Project::TOTAL_TESTS, $result->describe())
+        ->and($delta->writtenCount())->toBe(0, $delta->summary())
+        ->and($delta->added())->toBe(0, $delta->summary())
+        ->and($delta->removed())->toBe(0, $delta->summary())
+        ->and($project->graph()['baselines']['master']['results'])->toHaveCount(Project::TOTAL_TESTS);
+})->skipOnWindows();
+
+test('a project below the git repository root refuses to run and writes nothing', function (array $arguments): void {
+    $project = Project::make('master');
+    $nested = $project->nested();
+
+    $result = $project->pestIn($nested, '--tia', ...$arguments);
+
+    expect($result->exitCode)->toBe(1, $result->describe())
+        ->and($result->output)->toContain('Tia mode requires the git repository root')
+        ->and($project->path('.home/.pest'))->not->toBeDirectory()
+        ->and($nested.DIRECTORY_SEPARATOR.'.pest')->not->toBeDirectory();
+})->with(Project::SEQUENTIAL_AND_PARALLEL)->skipOnWindows();
+
+test('a repository with no commits says so, and leaves plain runs alone', function (): void {
+    $project = Project::withoutGit();
+    $project->git()->run(['init', '--quiet']);
+    $project->git()->run(['checkout', '--quiet', '-b', 'master']);
+    $project->git()->addOrigin();
+
+    $tia = $project->pest('--tia');
+
+    expect($tia->exitCode)->toBe(1, $tia->describe())
+        ->and($tia->output)->toContain('Tia mode requires at least one commit')
+        ->and($tia->output)->not->toContain('requires [git]')
+        ->and($project->graphExists())->toBeFalse();
+
+    $plain = $project->pest();
+
+    expect($plain->exitCode)->toBe(0, $plain->describe())
+        ->and($plain->tally())->toContain(Project::TOTAL_TESTS.' passed');
+})->skipOnWindows();
+
+test('a directory with no repository at all still asks for git', function (): void {
+    $project = Project::withoutGit();
+
+    $result = $project->pest('--tia');
+
+    expect($result->exitCode)->toBe(1, $result->describe())
+        ->and($result->output)->toContain('requires "git"')
+        ->and($project->graphExists())->toBeFalse();
+})->skipOnWindows();

tests/Features/Tia/CompleteRunWriteTier.php

@@ -0,0 +1,234 @@
+<?php
+
+declare(strict_types=1);
+
+use Tests\Fixtures\Tia\Project;
+
+afterEach(function (): void {
+    Project::destroyAll();
+});
+
+test('a complete run prunes a deleted test', function (array $arguments): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->write('tests/Unit/GreeterTest.php', <<<'PHP'
+        <?php
+
+        declare(strict_types=1);
+
+        use Fixture\App\Greeter;
+
+        test('greets a person', function (): void {
+            expect((new Greeter)->greet('Nuno'))->toBe('Hello, Nuno!');
+        });
+        PHP);
+
+    $result = $project->pest(...$arguments);
+    $delta = $project->delta();
+
+    expect($result->tally())->toContain('5 passed')
+        ->and($delta->removed())->toBe(1, $delta->summary())
+        ->and($delta->added())->toBe(0, $delta->summary())
+        ->and($delta->structureMoved())->toBeFalse($delta->summary());
+})->with(Project::SEQUENTIAL_AND_PARALLEL)->skipOnWindows();
+
+test('a complete run records nothing for a test file the graph does not know', function (): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->write('tests/Unit/BrandNewTest.php', <<<'PHP'
+        <?php
+
+        declare(strict_types=1);
+
+        test('brand new thing', function (): void {
+            expect(true)->toBeTrue();
+        });
+        PHP);
+
+    $result = $project->pest();
+    $delta = $project->delta();
+
+    expect($result->tally())->toContain('7 passed')
+        ->and($delta->added())->toBe(0, $delta->summary())
+        ->and($delta->removed())->toBe(0, $delta->summary())
+        ->and($delta->writtenCount())->toBe(Project::TOTAL_TESTS, $delta->summary());
+})->skipOnWindows();
+
+test('a partial run records nothing for a test file the graph does not know', function (): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->write('tests/Unit/BrandNewTest.php', <<<'PHP'
+        <?php
+
+        declare(strict_types=1);
+
+        test('brand new thing', function (): void {
+            expect(true)->toBeTrue();
+        });
+        PHP);
+
+    $result = $project->pest('--filter=brand new thing');
+    $delta = $project->delta();
+
+    expect($result->tally())->toContain('1 passed')
+        ->and($delta->added())->toBe(0, $delta->summary())
+        ->and($delta->writtenCount())->toBe(0, $delta->summary())
+        ->and($delta->isResultsOnly())->toBeTrue($delta->summary());
+})->skipOnWindows();
+
+test('a truncated run does not prune', function (array $arguments): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->write('tests/Unit/GreeterTest.php', <<<'PHP'
+        <?php
+
+        declare(strict_types=1);
+
+        use Fixture\App\Greeter;
+
+        test('greets a person', function (): void {
+            expect((new Greeter)->greet('Nuno'))->toBe('Goodbye, Nuno!');
+        });
+
+        test('greets the world', function (): void {
+            expect((new Greeter)->greet('world'))->toBe('Hello, world!');
+        });
+        PHP);
+
+    $result = $project->pest('--bail', ...$arguments);
+    $delta = $project->delta();
+
+    expect($result->exitCode)->toBe(1, $result->describe())
+        ->and($result->tally())->toContain('1 failed')
+        ->and($delta->removed())->toBe(0, $delta->summary())
+        ->and($delta->structureMoved())->toBeFalse($delta->summary());
+})->with(Project::SEQUENTIAL_AND_PARALLEL)->skipOnWindows();
+
+test('a green bail run is complete', function (): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $result = $project->pest('--bail');
+    $delta = $project->delta();
+
+    expect($result->exitCode)->toBe(0, $result->describe())
+        ->and($delta->writtenCount())->toBe(Project::TOTAL_TESTS, $delta->summary())
+        ->and($delta->removed())->toBe(0, $delta->summary())
+        ->and($delta->isResultsOnly())->toBeTrue($delta->summary());
+})->skipOnWindows();
+
+test('--no-tia refreshes results without enabling tia', function (array $arguments): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $result = $project->pest('--tia', '--no-tia', ...$arguments);
+    $delta = $project->delta();
+
+    expect($result->output)->not->toContain('Experimental TIA mode enabled')
+        ->and($result->tally())->toContain(Project::TOTAL_TESTS.' passed')
+        ->and($delta->writtenCount())->toBe(Project::TOTAL_TESTS, $delta->summary())
+        ->and($delta->isResultsOnly())->toBeTrue($delta->summary());
+})->with(Project::SEQUENTIAL_AND_PARALLEL)->skipOnWindows();
+
+test('a plain run refreshes the results it executed', function (array $arguments): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $result = $project->pest(...$arguments);
+    $delta = $project->delta();
+
+    expect($result->tally())->toContain(Project::TOTAL_TESTS.' passed')
+        ->and($delta->writtenCount())->toBe(Project::TOTAL_TESTS, $delta->summary())
+        ->and($delta->isResultsOnly())->toBeTrue($delta->summary());
+})->with(Project::SEQUENTIAL_AND_PARALLEL)->skipOnWindows();
+
+test('a parallel replay keeps the recorded time of tests that did not run', function (): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->pest('--tia', '--parallel', '--processes=2');
+
+    $delta = $project->delta();
+
+    expect($delta->writtenCount())->toBe(0, $delta->summary())
+        ->and($delta->isResultsOnly())->toBeTrue($delta->summary());
+})->skipOnWindows();
+
+test('a run that never enables tia creates no graph', function (array $arguments): void {
+    $project = Project::make('master');
+
+    $result = $project->pest(...$arguments);
+
+    expect($result->exitCode)->toBe(0, $result->describe())
+        ->and($project->graphExists())->toBeFalse();
+})->with([
+    'plain' => [[]],
+    'filtered' => [['--filter=adds two numbers']],
+    'parallel filtered' => [['--parallel', '--processes=2', '--filter=adds two numbers']],
+])->skipOnWindows();
+
+test('a test edit narrows to the affected file and replays the rest', function (): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->write('tests/Unit/GreeterTest.php', <<<'PHP'
+        <?php
+
+        declare(strict_types=1);
+
+        use Fixture\App\Greeter;
+
+        test('greets a person', function (): void {
+            expect((new Greeter)->greet('Nuno'))->toBe('Hello, Nuno!');
+            expect((new Greeter)->greet('Nuno'))->toBeString();
+        });
+
+        test('greets the world', function (): void {
+            expect((new Greeter)->greet('world'))->toBe('Hello, world!');
+        });
+        PHP);
+
+    $result = $project->pest('--tia');
+    $delta = $project->delta();
+
+    expect($result->affected())->toBe(2, $result->describe())
+        ->and($result->replayed())->toBe(4, $result->describe())
+        ->and($delta->writtenCount())->toBe(2, $delta->summary())
+        ->and($delta->edgesMoved())->toBeFalse($delta->summary())
+        ->and($delta->removed())->toBe(0, $delta->summary());
+})->skipOnWindows();
+
+test('a parallel run merges worker results into the parent baseline', function (): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->write('tests/Unit/GreeterTest.php', <<<'PHP'
+        <?php
+
+        declare(strict_types=1);
+
+        use Fixture\App\Greeter;
+
+        test('greets a person', function (): void {
+            expect((new Greeter)->greet('Nuno'))->toBe('Hello, Nuno!');
+            expect((new Greeter)->greet('Nuno'))->toBeString();
+        });
+
+        test('greets the world', function (): void {
+            expect((new Greeter)->greet('world'))->toBe('Hello, world!');
+        });
+        PHP);
+
+    $result = $project->pest('--tia', '--parallel', '--processes=2');
+    $delta = $project->delta();
+
+    expect($result->affected())->toBe(2, $result->describe())
+        ->and($result->replayed())->toBe(4, $result->describe())
+        ->and($delta->writtenCount())->toBe(2, $delta->summary())
+        ->and($delta->edgesMoved())->toBeFalse($delta->summary())
+        ->and($delta->removed())->toBe(0, $delta->summary());
+})->skipOnWindows();

tests/Features/Tia/CoveragePiggyback.php

@@ -0,0 +1,53 @@
+<?php
+
+declare(strict_types=1);
+
+use Tests\Fixtures\Tia\Project;
+
+afterEach(function (): void {
+    Project::destroyAll();
+});
+
+test('a coverage report does not found a dependency graph', function (array $arguments): void {
+    $project = Project::make('master');
+
+    $project->pest('--tia', ...$arguments);
+
+    expect($project->graphExists())->toBeFalse();
+})->with([
+    'pest coverage' => [['--coverage']],
+    'phpunit coverage report' => [['--coverage-text']],
+    'parallel' => [['--coverage', '--parallel', '--processes=2']],
+])->skipOnWindows();
+
+test('a plain run after a coverage run records the whole project scope', function (): void {
+    $project = Project::make('master');
+
+    $project->pest('--tia', '--coverage');
+    $project->pest('--tia');
+
+    $graph = $project->graph();
+
+    if ($graph === null) {
+        expect($project->graphExists())->toBeFalse();
+
+        return;
+    }
+
+    expect(array_keys($graph['edges']))->toEqualCanonicalizing(array_keys(Project::EDGES))
+        ->and($graph['files'])->toContain('tests/Unit/CalculatorTest.php')
+        ->and($graph['files'])->toContain('app/Calculator.php');
+})->skipOnWindows();
+
+test('a coverage report leaves the edges of an existing graph alone', function (): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->pest('--tia', '--coverage');
+    $delta = $project->delta();
+
+    expect($delta->edgesMoved())->toBeFalse($delta->summary())
+        ->and($delta->filesMoved())->toBeFalse($delta->summary())
+        ->and($delta->removed())->toBe(0, $delta->summary())
+        ->and($delta->added())->toBe(0, $delta->summary());
+})->skipOnWindows();

tests/Features/Tia/DefaultBranchReplay.php

@@ -0,0 +1,139 @@
+<?php
+
+declare(strict_types=1);
+
+use Tests\Fixtures\Tia\Project;
+
+afterEach(function (): void {
+    Project::destroyAll();
+});
+
+test('replays the default branch baseline on a new branch', function (): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->git()->switchTo('feature-x', new: true);
+
+    $result = $project->pest('--tia');
+
+    expect($result->replayed())->toBe(Project::TOTAL_TESTS, $result->describe())
+        ->and($result->uncached())->toBe(0, $result->describe())
+        ->and($result->exitCode)->toBe(0);
+})->skipOnWindows();
+
+test('replays whatever the default branch is called', function (string $defaultBranch): void {
+    $project = Project::make($defaultBranch);
+    $project->seed($defaultBranch);
+
+    $project->git()->switchTo('feature-x', new: true);
+
+    $result = $project->pest('--tia');
+
+    expect($result->replayed())->toBe(Project::TOTAL_TESTS, $result->describe())
+        ->and($result->uncached())->toBe(0, $result->describe());
+})->with(['main', 'master', 'trunk', 'develop'])->skipOnWindows();
+
+test('replays on a second new branch too', function (): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->git()->switchTo('feature-x', new: true);
+    $project->pest('--tia');
+
+    $project->git()->switchTo('master');
+    $project->git()->switchTo('feature-y', new: true);
+
+    $result = $project->pest('--tia');
+
+    expect($result->replayed())->toBe(Project::TOTAL_TESTS, $result->describe())
+        ->and($result->uncached())->toBe(0, $result->describe());
+})->skipOnWindows();
+
+test('writes nothing on a second run on the same branch', function (): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->git()->switchTo('feature-x', new: true);
+    $project->pest('--tia');
+
+    $project->snapshot();
+    $result = $project->pest('--tia');
+    $delta = $project->delta();
+
+    expect($result->replayed())->toBe(Project::TOTAL_TESTS, $result->describe())
+        ->and($delta->writtenCount())->toBe(0, $delta->summary())
+        ->and($delta->isResultsOnly())->toBeTrue($delta->summary());
+})->skipOnWindows();
+
+test('replays on a branch whose name contains slashes', function (): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->git()->switchTo('feature/x/y', new: true);
+
+    $result = $project->pest('--tia');
+
+    expect($result->replayed())->toBe(Project::TOTAL_TESTS, $result->describe())
+        ->and($result->uncached())->toBe(0, $result->describe())
+        ->and($project->branchKeys())->toContain('feature/x/y');
+})->skipOnWindows();
+
+test('replays again once back on the default branch', function (): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->git()->switchTo('feature-x', new: true);
+    $project->pest('--tia');
+
+    $project->git()->switchTo('master');
+
+    $project->snapshot();
+    $result = $project->pest('--tia');
+    $delta = $project->delta();
+
+    expect($result->replayed())->toBe(Project::TOTAL_TESTS, $result->describe())
+        ->and($result->uncached())->toBe(0, $result->describe())
+        ->and($delta->writtenCount())->toBe(0, $delta->summary())
+        ->and($delta->isResultsOnly())->toBeTrue($delta->summary());
+})->skipOnWindows();
+
+test('replays on a new branch when tia is enabled by configuration', function (): void {
+    $project = Project::make('master', overlay: 'always-enabled');
+    $project->seed('master');
+
+    $project->git()->switchTo('feature-x', new: true);
+
+    $result = $project->pest();
+
+    expect($result->replayed())->toBe(Project::TOTAL_TESTS, $result->describe())
+        ->and($result->uncached())->toBe(0, $result->describe())
+        ->and($project->branchKeys())->toBe(['master', 'feature-x']);
+})->skipOnWindows();
+
+test('a narrowed run on a new branch does not cost the fallback', function (array $arguments): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->git()->switchTo('feature-x', new: true);
+    $project->pest(...$arguments);
+
+    $result = $project->pest('--tia');
+
+    expect($result->replayed())->toBe(Project::TOTAL_TESTS, $result->describe())
+        ->and($result->uncached())->toBe(0, $result->describe());
+})->with([
+    'sequential' => [['--filter=adds two numbers']],
+    'parallel' => [['--parallel', '--processes=2', '--filter=adds two numbers']],
+])->skipOnWindows();
+
+test('replays inside a worktree on a new branch', function (): void {
+    $project = Project::make('master');
+    $worktree = $project->worktree('feature-worktree');
+
+    $project->seedFor($worktree, 'master');
+
+    $result = $project->pestIn($worktree, '--tia');
+
+    expect($result->replayed())->toBe(Project::TOTAL_TESTS, $result->describe())
+        ->and($result->uncached())->toBe(0, $result->describe());
+})->skipOnWindows();

tests/Features/Tia/DefaultBranchResolution.php

@@ -0,0 +1,223 @@
+<?php
+
+declare(strict_types=1);
+
+use Symfony\Component\Process\ExecutableFinder;
+use Tests\Fixtures\Tia\Project;
+
+afterEach(function (): void {
+    Project::destroyAll();
+});
+
+test('a declared default branch beats autodetection', function (): void {
+    $project = Project::make('develop', overlay: 'configured-default-branch');
+    $project->seed('master');
+
+    $project->git()->switchTo('feature-x', new: true);
+
+    $result = $project->pest('--tia');
+
+    expect($result->replayed())->toBe(Project::TOTAL_TESTS, $result->describe())
+        ->and($result->uncached())->toBe(0, $result->describe());
+})->skipOnWindows();
+
+test('a declared default branch that does not exist degrades to a full run', function (): void {
+    $project = Project::make('master', overlay: 'unknown-default-branch');
+    $project->seed('master');
+
+    $project->git()->switchTo('feature-x', new: true);
+
+    $result = $project->pest('--tia');
+
+    expect($result->uncached())->toBe(Project::TOTAL_TESTS, $result->describe())
+        ->and($result->exitCode)->toBe(0, $result->describe())
+        ->and($project->branchKeys())->toBe(['master', 'feature-x']);
+})->skipOnWindows();
+
+test('a renamed default branch replays and writes under its new name', function (): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->git()->rename('master', 'main');
+
+    $result = $project->pest('--tia');
+    $delta = $project->delta();
+
+    expect($result->replayed())->toBe(Project::TOTAL_TESTS, $result->describe())
+        ->and($result->uncached())->toBe(0, $result->describe())
+        ->and($project->branchKeys())->toBe(['master', 'main'])
+        ->and($delta->baselineUntouched('master'))->toBeTrue($delta->summary())
+        ->and($delta->writtenCount())->toBe(0, $delta->summary());
+})->skipOnWindows();
+
+test('the CI provider names the default branch where the checkout cannot', function (): void {
+    $project = Project::make('master');
+    $project->git()->unsetOriginHead();
+    $project->seed('master');
+    $project->addBaseline('legacy');
+
+    $project->git()->switchTo('feature-x', new: true);
+
+    $project->write('.home/event.json', (string) json_encode([
+        'repository' => ['default_branch' => 'master'],
+    ]));
+
+    $result = $project->pestWithEnvironment($project->path(), [
+        'GITHUB_EVENT_PATH' => $project->path('.home/event.json'),
+    ], '--tia');
+
+    expect($result->replayed())->toBe(Project::TOTAL_TESTS, $result->describe())
+        ->and($result->uncached())->toBe(0, $result->describe());
+})->skipOnWindows();
+
+test('GitLab names the default branch through its own variable', function (): void {
+    $project = Project::make('master');
+    $project->git()->unsetOriginHead();
+    $project->seed('master');
+    $project->addBaseline('legacy');
+
+    $project->git()->switchTo('feature-x', new: true);
+
+    $result = $project->pestWithEnvironment($project->path(), [
+        'CI_DEFAULT_BRANCH' => 'master',
+    ], '--tia');
+
+    expect($result->replayed())->toBe(Project::TOTAL_TESTS, $result->describe())
+        ->and($result->uncached())->toBe(0, $result->describe());
+})->skipOnWindows();
+
+test('a lone recorded baseline names the default branch', function (): void {
+    $project = Project::make('master');
+    $project->git()->unsetOriginHead();
+    $project->git()->config('init.defaultBranch', 'main');
+    $project->seed('master');
+
+    $project->git()->switchTo('feature-x', new: true);
+
+    $result = $project->pest('--tia');
+
+    expect($result->replayed())->toBe(Project::TOTAL_TESTS, $result->describe())
+        ->and($result->uncached())->toBe(0, $result->describe());
+})->skipOnWindows();
+
+test('a default branch nothing can name is refused rather than guessed', function (): void {
+    $project = Project::make('master');
+    $project->git()->unsetOriginHead();
+    $project->git()->config('init.defaultBranch', 'main');
+
+    $project->git()->switchTo('feature-x', new: true);
+
+    $result = $project->pest('--tia');
+
+    expect($result->output)->toContain('Tia mode could not determine the default branch.')
+        ->and($result->output)->toContain('git remote set-head origin --auto')
+        ->and($result->exitCode)->toBe(1, $result->describe())
+        ->and($project->graphExists())->toBeFalse();
+})->skipOnWindows();
+
+test('an init.defaultBranch naming a branch that exists is still trusted', function (): void {
+    $project = Project::make('master');
+    $project->git()->unsetOriginHead();
+    $project->git()->config('init.defaultBranch', 'master');
+
+    $project->git()->switchTo('feature-x', new: true);
+
+    $result = $project->pest('--tia');
+
+    expect($result->exitCode)->toBe(0, $result->describe())
+        ->and($result->output)->not->toContain('could not determine the default branch')
+        ->and($project->branchKeys())->not->toContain('master');
+})->skipOnWindows();
+
+test('a repository with no remote is refused rather than silently re-run', function (): void {
+    $project = Project::make('master');
+
+    $project->git()->removeOrigin();
+
+    $project->git()->switchTo('feature-x', new: true);
+
+    $result = $project->pest('--tia');
+
+    expect($result->output)->toContain('Tia mode requires a repository with a remote.')
+        ->and($result->exitCode)->toBe(1, $result->describe());
+})->skipOnWindows();
+
+test('a remote-less repository holding one baseline is not refused', function (): void {
+    $project = Project::make('master');
+
+    $project->git()->removeOrigin();
+    $project->seed('master');
+
+    $project->git()->switchTo('feature-x', new: true);
+
+    $result = $project->pest('--tia');
+
+    expect($result->replayed())->toBe(Project::TOTAL_TESTS, $result->describe())
+        ->and($result->uncached())->toBe(0, $result->describe());
+})->skipOnWindows();
+
+test('a declared default branch stands in for a missing remote', function (): void {
+    $project = Project::make('master', overlay: 'configured-default-branch');
+
+    $project->git()->removeOrigin();
+    $project->seed('master');
+
+    $project->git()->switchTo('feature-x', new: true);
+
+    $result = $project->pest('--tia');
+
+    expect($result->replayed())->toBe(Project::TOTAL_TESTS, $result->describe())
+        ->and($result->uncached())->toBe(0, $result->describe());
+})->skipOnWindows();
+
+test('tia still requires git', function (): void {
+    $project = Project::withoutGit();
+
+    $result = $project->pest('--tia');
+
+    expect($result->output)->toContain('The feature [Tia mode[ requires [git].')
+        ->and($result->exitCode)->not->toBe(0);
+})->skipOnWindows();
+
+test('a plain run outside a repository creates no baseline', function (): void {
+    $project = Project::withoutGit();
+
+    $result = $project->pest();
+
+    expect($result->exitCode)->toBe(0, $result->describe())
+        ->and($result->tally())->toContain(Project::TOTAL_TESTS.' passed')
+        ->and($project->graphExists())->toBeFalse()
+        ->and($project->graphDir())->not->toBeDirectory();
+})->skipOnWindows();
+
+test('the default branch is resolved once per run, not once per test', function (): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->git()->switchTo('feature-x', new: true);
+
+    $git = (new ExecutableFinder)->find('git');
+
+    expect($git)->not->toBeNull();
+
+    $log = $project->path('git-calls.log');
+    $project->write('shim/git', implode("\n", [
+        '#!/bin/sh',
+        'echo "$@" >> '.escapeshellarg($log),
+        'exec '.escapeshellarg((string) $git).' "$@"',
+        '',
+    ]));
+    chmod($project->path('shim/git'), 0755);
+
+    $result = $project->pestWithEnvironment($project->path(), [
+        'PATH' => $project->path('shim').':'.getenv('PATH'),
+    ], '--tia');
+
+    $calls = file_exists($log) ? explode("\n", trim((string) file_get_contents($log))) : [];
+    $resolutions = array_filter($calls, fn (string $call): bool => str_contains($call, 'symbolic-ref')
+        || str_contains($call, 'init.defaultBranch'));
+
+    expect($result->replayed())->toBe(Project::TOTAL_TESTS, $result->describe())
+        ->and($calls)->not->toBeEmpty('the git shim was never reached')
+        ->and($resolutions)->toHaveCount(1, implode("\n", $calls));
+})->skipOnWindows();

tests/Features/Tia/DefaultBranchWriteTier.php

@@ -0,0 +1,160 @@
+<?php
+
+declare(strict_types=1);
+
+use Tests\Fixtures\Tia\Project;
+
+afterEach(function (): void {
+    Project::destroyAll();
+});
+
+test('narrows to the affected tests on a new branch', function (): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->git()->switchTo('feature-x', new: true);
+
+    $project->write('tests/Unit/GreeterTest.php', <<<'PHP'
+        <?php
+
+        declare(strict_types=1);
+
+        use Fixture\App\Greeter;
+
+        test('greets a person', function (): void {
+            expect((new Greeter)->greet('Nuno'))->toBe('Hello, Nuno!');
+            expect((new Greeter)->greet('Nuno'))->toBeString();
+        });
+
+        test('greets the world', function (): void {
+            expect((new Greeter)->greet('world'))->toBe('Hello, world!');
+        });
+        PHP);
+
+    $result = $project->pest('--tia');
+    $delta = $project->delta();
+
+    expect($result->affected())->toBe(2, $result->describe())
+        ->and($result->replayed())->toBe(4, $result->describe())
+        ->and($result->exitCode)->toBe(0, $result->describe())
+        ->and($project->branchKeys())->toBe(['master', 'feature-x'])
+        ->and($delta->baselineUntouched('master'))->toBeTrue($delta->summary())
+        ->and($delta->edgesMoved())->toBeFalse($delta->summary());
+})->skipOnWindows();
+
+test('filtered mode reads the fallback too', function (): void {
+    $project = Project::make('master');
+
+    $project->seed('master', failing: ['adds two numbers']);
+
+    $project->git()->switchTo('feature-x', new: true);
+
+    $result = $project->pest('--tia', '--filtered');
+
+    expect($result->output)->toContain('from 1 previously unsuccessful test')
+        ->and($result->output)->not->toContain('No affected tests found')
+        ->and($result->tally())->toContain('2 passed');
+})->skipOnWindows();
+
+test('filtered mode finds nothing to do on a clean green feature branch', function (): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->git()->switchTo('feature-x', new: true);
+
+    $result = $project->pest('--tia', '--filtered');
+    $delta = $project->delta();
+
+    expect($result->output)->toContain('No affected tests found')
+        ->and($result->exitCode)->toBe(0, $result->describe())
+        ->and($delta->isHardSuppressed())->toBeTrue($delta->summary());
+})->skipOnWindows();
+
+test('filtered mode falls back to a full replay when a cached failure cannot be located', function (): void {
+    $project = Project::make('master');
+
+    $project->seed('master', failing: ['adds two numbers']);
+
+    $project->mutateGraph(function (array $graph): array {
+        $testId = Project::testId('tests/Unit/CalculatorTest.php', 'adds two numbers');
+
+        $graph['baselines']['master']['results'][$testId]['file'] = '/build/agent/tests/Unit/DeletedTest.php';
+
+        return $graph;
+    });
+
+    $project->git()->switchTo('feature-x', new: true);
+
+    $result = $project->pest('--tia', '--filtered');
+
+    expect($result->output)->toContain('Some cached tests due a re-run could not be located on disk.')
+        ->and($result->output)->toContain('Running the full suite with replay instead of a filtered run.')
+        ->and($result->output)->not->toContain('No affected tests found');
+})->skipOnWindows();
+
+test('filtered mode finds nothing to do on the default branch itself', function (): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $result = $project->pest('--tia', '--filtered');
+    $delta = $project->delta();
+
+    expect($result->output)->toContain('No affected tests found')
+        ->and($result->exitCode)->toBe(0, $result->describe())
+        ->and($delta->isHardSuppressed())->toBeTrue($delta->summary());
+})->skipOnWindows();
+
+test('a detached HEAD replays without minting a branch key', function (): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->git()->detach();
+
+    $result = $project->pest('--tia');
+
+    expect($result->replayed())->toBe(Project::TOTAL_TESTS, $result->describe())
+        ->and($result->uncached())->toBe(0, $result->describe())
+        ->and($project->branchKeys())->toBe(['master']);
+})->skipOnWindows();
+
+test('a detached HEAD does not write into the default branch baseline', function (array $arguments): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->git()->detach();
+    $project->pest(...$arguments);
+
+    $delta = $project->delta();
+
+    expect($delta->baselineUntouched('master'))->toBeTrue($delta->summary())
+        ->and($project->branchKeys())->toBe(['master']);
+})->with([
+    'sequential' => [['--filter=adds two numbers']],
+    'parallel' => [['--parallel', '--processes=2', '--filter=adds two numbers']],
+])->skipOnWindows();
+
+test('the branch that ran gets its own key and the default branch keeps its baseline', function (): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->git()->switchTo('feature-x', new: true);
+    $project->pest('--tia');
+
+    $delta = $project->delta();
+
+    expect($project->branchKeys())->toBe(['master', 'feature-x'])
+        ->and($delta->baselineUntouched('master'))->toBeTrue($delta->summary())
+        ->and($delta->writtenCount())->toBe(0, $delta->summary());
+})->skipOnWindows();
+
+test('the fallback reaches parallel workers', function (): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->git()->switchTo('feature-x', new: true);
+
+    $result = $project->pest('--tia', '--parallel', '--processes=2');
+
+    expect($result->replayed())->toBe(Project::TOTAL_TESTS, $result->describe())
+        ->and($result->uncached())->toBe(0, $result->describe());
+})->skipOnWindows();

tests/Features/Tia/FilteredMode.php

@@ -0,0 +1,87 @@
+<?php
+
+declare(strict_types=1);
+
+use Tests\Fixtures\Tia\Project;
+
+afterEach(function (): void {
+    Project::destroyAll();
+});
+
+test('re-runs a cached failure on a clean tree', function (): void {
+    $project = Project::make('master');
+    $project->seed('master', failing: ['adds two numbers']);
+
+    $result = $project->pest('--tia', '--filtered');
+    $delta = $project->delta();
+
+    expect($result->output)->toContain('from 1 previously unsuccessful test')
+        ->and($result->affected())->toBe(2, $result->describe())
+        ->and($result->tally())->toContain('2 passed')
+        ->and($delta->writtenCount())->toBe(2, $delta->summary())
+        ->and($delta->isResultsOnly())->toBeTrue($delta->summary());
+})->skipOnWindows();
+
+test('an explicit path turns filtered mode off', function (): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $result = $project->pest('--tia', '--filtered', 'tests/Unit');
+    $delta = $project->delta();
+
+    expect($result->output)->toContain('TIA does not apply to partial runs')
+        ->and($result->output)->not->toContain('No affected tests found')
+        ->and($result->tally())->toContain('4 passed')
+        ->and($delta->writtenCount())->toBe(4, $delta->summary())
+        ->and($delta->isResultsOnly())->toBeTrue($delta->summary());
+})->skipOnWindows();
+
+test('filtered mode runs the whole suite when there is no baseline', function (): void {
+    $project = Project::make('master');
+
+    $result = $project->pest('--tia', '--filtered');
+
+    expect($result->exitCode)->toBe(0, $result->describe())
+        ->and($result->tally())->toContain(Project::TOTAL_TESTS.' passed')
+        ->and($result->output)->not->toContain('No affected tests found');
+})->skipOnWindows();
+
+test('filtered mode finds nothing to do in parallel either', function (): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $result = $project->pest('--tia', '--filtered', '--parallel', '--processes=2');
+    $delta = $project->delta();
+
+    expect($result->output)->toContain('No affected tests found')
+        ->and($result->exitCode)->toBe(0, $result->describe())
+        ->and($delta->isHardSuppressed())->toBeTrue($delta->summary());
+})->skipOnWindows();
+
+test('a corrupt graph is reported and does not crash the run', function (): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $graph = $project->graphDir().'/graph.json';
+
+    file_put_contents($graph, '{not json');
+
+    $result = $project->pest('--tia');
+
+    expect($result->exitCode)->toBe(0, $result->describe())
+        ->and($result->tally())->toContain(Project::TOTAL_TESTS.' passed')
+        ->and($result->output)->toContain('The dependency graph could not be read')
+        ->and(is_file($graph) ? file_get_contents($graph) : null)->not->toBe('{not json');
+})->skipOnWindows();
+
+test('--parallel --retry is refused and leaves the graph alone', function (): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $result = $project->pest('--parallel', '--retry');
+    $delta = $project->delta();
+
+    expect($result->exitCode)->not->toBe(0)
+        ->and($result->output)->toContain('--retry')
+        ->and($delta->isHardSuppressed())->toBeTrue($delta->summary());
+})->skipOnWindows();

tests/Features/Tia/HostileState.php

@@ -0,0 +1,221 @@
+<?php
+
+declare(strict_types=1);
+
+use Tests\Fixtures\Tia\Project;
+
+afterEach(function (): void {
+    Project::destroyAll();
+});
+
+test('a graph mangled beyond use still lets the suite run', function (string $contents): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    file_put_contents($project->graphDir().'/graph.json', $contents);
+
+    $result = $project->pest('--tia');
+
+    expect($result->exitCode)->toBe(0, $result->describe())
+        ->and($result->tally())->toContain(Project::TOTAL_TESTS.' passed');
+})->with([
+    'empty' => '',
+    'truncated' => '{"schema":1,"files":["app/Calculator.php"],"edg',
+    'not json' => '{not json',
+    'json scalar' => '"just a string"',
+    'json list' => '[1,2,3]',
+    'json null' => 'null',
+    'empty object' => '{}',
+    'nul bytes' => "\0\0\0\0",
+])->skipOnWindows();
+
+test('a graph whose shape is wrong everywhere is repaired rather than trusted', function (array $arguments): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->mutateGraph(function (array $graph): array {
+        $id = Project::testId('tests/Unit/CalculatorTest.php', 'adds two numbers');
+
+        $graph['baselines']['master']['results'][$id] = 'nope';
+        $graph['baselines']['master']['results'][7] = ['status' => 0, 'message' => '', 'time' => 0.1];
+        $graph['baselines']['master']['tree'] = 'nope';
+        $graph['baselines']['master']['sha'] = 42;
+        $graph['baselines'][''] = ['sha' => null, 'tree' => [], 'results' => []];
+        $graph['baselines']['broken'] = 'nope';
+        $graph['edges']['tests/Unit/GreeterTest.php'] = 'nope';
+        $graph['edges'][''] = [0];
+        $graph['files'][] = ['nested'];
+
+        return $graph;
+    });
+
+    $result = $project->pest('--tia', ...$arguments);
+
+    expect($result->exitCode)->toBe(0, $result->describe())
+        ->and($result->output)->not->toContain('TypeError')
+        ->and($result->tally())->toContain(Project::TOTAL_TESTS.' passed')
+        ->and($project->branchKeys())->toBe(['master']);
+})->with(Project::SEQUENTIAL_AND_PARALLEL)->skipOnWindows();
+
+test('a cached status this build cannot interpret is re-run, not replayed', function (int $status): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->mutateGraph(function (array $graph) use ($status): array {
+        $id = Project::testId('tests/Unit/CalculatorTest.php', 'adds two numbers');
+        $graph['baselines']['master']['results'][$id]['status'] = $status;
+
+        return $graph;
+    });
+
+    $result = $project->pest('--tia');
+
+    expect($result->exitCode)->toBe(0, $result->describe())
+        ->and($result->tally())->toContain(Project::TOTAL_TESTS.' passed')
+        ->and($result->uncached())->toBe(1, $result->describe());
+})->with([
+    'below the range' => -1,
+    'one past the range' => 9,
+    'far past the range' => 99,
+    'huge' => PHP_INT_MAX,
+])->skipOnWindows();
+
+test('a cached status with no replay of its own does not fail the run', function (int $status): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->mutateGraph(function (array $graph) use ($status): array {
+        $id = Project::testId('tests/Unit/CalculatorTest.php', 'adds two numbers');
+        $graph['baselines']['master']['results'][$id]['status'] = $status;
+        $graph['baselines']['master']['results'][$id]['message'] = 'cached detail';
+
+        return $graph;
+    });
+
+    $result = $project->pest('--tia');
+
+    expect($result->exitCode)->toBe(0, $result->describe())
+        ->and($result->tally())->toContain(Project::TOTAL_TESTS.' passed');
+})->with(['notice' => 3, 'deprecation' => 4, 'warning' => 6])->skipOnWindows();
+
+test('a cached skip or todo replays with its message intact', function (int $status, string $tally): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->mutateGraph(function (array $graph) use ($status): array {
+        $id = Project::testId('tests/Unit/CalculatorTest.php', 'adds two numbers');
+        $graph['baselines']['master']['results'][$id]['status'] = $status;
+        $graph['baselines']['master']['results'][$id]['message'] = 'a recorded reason';
+
+        return $graph;
+    });
+
+    $result = $project->pest('--tia');
+
+    expect($result->exitCode)->toBe(0, $result->describe())
+        ->and($result->tally())->toContain($tally)
+        ->and($result->output)->toContain('a recorded reason')
+        ->and($result->replayed())->toBe(Project::TOTAL_TESTS, $result->describe());
+})->with([
+    'skipped' => [1, '1 skipped'],
+    'incomplete' => [2, '1 incomplete'],
+])->skipOnWindows();
+
+test('a cached failure with a multi-line message re-runs rather than replaying the text', function (): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->mutateGraph(function (array $graph): array {
+        $id = Project::testId('tests/Unit/CalculatorTest.php', 'adds two numbers');
+        $graph['baselines']['master']['results'][$id]['status'] = 7;
+        $graph['baselines']['master']['results'][$id]['message'] = "line one\nline two\nline three";
+
+        return $graph;
+    });
+
+    $result = $project->pest('--tia');
+
+    expect($result->exitCode)->toBe(0, $result->describe())
+        ->and($result->uncached())->toBe(1, $result->describe())
+        ->and($result->tally())->toContain(Project::TOTAL_TESTS.' passed');
+})->skipOnWindows();
+
+test('a result pointing outside the project is not addressable and widens the run', function (): void {
+    $project = Project::make('master');
+    $project->seed('master', failing: ['adds two numbers']);
+
+    $project->mutateGraph(function (array $graph): array {
+        $id = Project::testId('tests/Unit/CalculatorTest.php', 'adds two numbers');
+        $graph['baselines']['master']['results'][$id]['file'] = '/build/agent/tests/Unit/CalculatorTest.php';
+
+        return $graph;
+    });
+
+    $result = $project->pest('--tia', '--filtered');
+
+    expect($result->exitCode)->toBe(0, $result->describe())
+        ->and($result->output)->toContain('could not be located on disk')
+        ->and($result->tally())->toContain(Project::TOTAL_TESTS.' passed');
+})->skipOnWindows();
+
+test('an edge pointing at a file id that does not exist is ignored', function (): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->mutateGraph(function (array $graph): array {
+        $graph['edges']['tests/Unit/CalculatorTest.php'] = [0, 999, -5];
+
+        return $graph;
+    });
+
+    $result = $project->pest('--tia');
+
+    expect($result->exitCode)->toBe(0, $result->describe())
+        ->and($result->replayed())->toBe(Project::TOTAL_TESTS, $result->describe());
+})->skipOnWindows();
+
+test('a graph from a schema this build does not know is rebuilt, not read', function (): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->mutateGraph(function (array $graph): array {
+        $graph['schema'] = 2;
+
+        return $graph;
+    });
+
+    $result = $project->pest('--tia');
+
+    expect($result->exitCode)->toBe(0, $result->describe())
+        ->and($result->tally())->toContain(Project::TOTAL_TESTS.' passed')
+        ->and($result->replayed())->toBe(0, $result->describe());
+})->skipOnWindows();
+
+test('graph.json being a directory does not stop the run', function (): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    unlink($project->graphDir().'/graph.json');
+    mkdir($project->graphDir().'/graph.json');
+
+    $result = $project->pest('--tia');
+
+    expect($result->exitCode)->toBe(0, $result->describe())
+        ->and($result->tally())->toContain(Project::TOTAL_TESTS.' passed');
+})->skipOnWindows();
+
+test('a state dir it cannot write to still replays', function (): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    chmod($project->graphDir(), 0500);
+
+    try {
+        $result = $project->pest('--tia');
+    } finally {
+        chmod($project->graphDir(), 0700);
+    }
+
+    expect($result->exitCode)->toBe(0, $result->describe())
+        ->and($result->replayed())->toBe(Project::TOTAL_TESTS, $result->describe());
+})->skipOnWindows();

tests/Features/Tia/IssueStatuses.php

@@ -0,0 +1,136 @@
+<?php
+
+declare(strict_types=1);
+
+use Tests\Fixtures\Tia\Project;
+
+afterEach(function (): void {
+    Project::destroyAll();
+});
+
+function tiaTriggering(string $call): string
+{
+    return <<<PHP
+    <?php
+
+    declare(strict_types=1);
+
+    use Fixture\App\Calculator;
+
+    test('adds two numbers', function (): void {
+        {$call}
+        expect((new Calculator)->add(1, 2))->toBe(3);
+    });
+
+    test('subtracts two numbers', function (): void {
+        expect((new Calculator)->subtract(3, 1))->toBe(2);
+    });
+    PHP;
+}
+
+test('a triggered issue is recorded as itself, not as a pass', function (array $arguments, string $call, int $status): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->write('tests/Unit/CalculatorTest.php', tiaTriggering($call));
+    $project->git()->commit('trigger an issue');
+
+    $project->pest('--tia', ...$arguments);
+
+    $id = Project::testId('tests/Unit/CalculatorTest.php', 'adds two numbers');
+
+    expect($project->graph()['baselines']['master']['results'][$id]['status'])->toBe($status);
+})->with(Project::SEQUENTIAL_AND_PARALLEL)->with([
+    'deprecation' => ["trigger_error('legacy adder', E_USER_DEPRECATED);", 4],
+    'notice' => ["trigger_error('a notice', E_USER_NOTICE);", 3],
+    'warning' => ["trigger_error('a warning', E_USER_WARNING);", 6],
+])->skipOnWindows();
+
+test('a cached deprecation still fails the run that asked to fail on one', function (array $arguments): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->write('tests/Unit/CalculatorTest.php', tiaTriggering("trigger_error('legacy adder', E_USER_DEPRECATED);"));
+    $project->git()->commit('trigger a deprecation');
+
+    $project->pest('--tia', ...$arguments);
+
+    $result = $project->pest('--tia', '--fail-on-deprecation', ...$arguments);
+
+    expect($result->exitCode)->toBe(1, $result->describe())
+        ->and($result->tally())->toContain('1 deprecated')
+        ->and($result->uncached())->toBe(1, $result->describe());
+})->with(Project::SEQUENTIAL_AND_PARALLEL)->skipOnWindows();
+
+test('replaying a cached issue does not downgrade it to a pass', function (array $arguments): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->write('tests/Unit/CalculatorTest.php', tiaTriggering("trigger_error('legacy adder', E_USER_DEPRECATED);"));
+    $project->git()->commit('trigger a deprecation');
+
+    $project->pest('--tia', ...$arguments);
+
+    $id = Project::testId('tests/Unit/CalculatorTest.php', 'adds two numbers');
+
+    foreach (range(1, 3) as $ignored) {
+        $project->pest('--tia', ...$arguments);
+
+        expect($project->graph()['baselines']['master']['results'][$id]['status'])->toBe(4);
+    }
+
+    $result = $project->pest('--tia', '--fail-on-deprecation', ...$arguments);
+
+    expect($result->exitCode)->toBe(1, $result->describe());
+})->with(Project::SEQUENTIAL_AND_PARALLEL)->skipOnWindows();
+
+test('a failure outranks an issue triggered on the way to it', function (): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->write('tests/Unit/CalculatorTest.php', str_replace(
+        'toBe(3)',
+        'toBe(999)',
+        tiaTriggering("trigger_error('legacy adder', E_USER_DEPRECATED);"),
+    ));
+    $project->git()->commit('an issue then a failure');
+
+    $result = $project->pest('--tia');
+
+    $id = Project::testId('tests/Unit/CalculatorTest.php', 'adds two numbers');
+
+    expect($result->exitCode)->not->toBe(0)
+        ->and($project->graph()['baselines']['master']['results'][$id]['status'])->toBe(7);
+})->skipOnWindows();
+
+test('a skip outranks an issue triggered on the way to it', function (): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->write('tests/Unit/CalculatorTest.php', str_replace(
+        'expect((new Calculator)->add(1, 2))->toBe(3);',
+        "\$this->markTestSkipped('not today');",
+        tiaTriggering("trigger_error('legacy adder', E_USER_DEPRECATED);"),
+    ));
+    $project->git()->commit('an issue then a skip');
+
+    $project->pest('--tia');
+
+    $id = Project::testId('tests/Unit/CalculatorTest.php', 'adds two numbers');
+
+    expect($project->graph()['baselines']['master']['results'][$id]['status'])->toBe(1);
+})->skipOnWindows();
+
+test('a suppressed issue is not recorded', function (): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->write('tests/Unit/CalculatorTest.php', tiaTriggering("@trigger_error('quiet', E_USER_DEPRECATED);"));
+    $project->git()->commit('a suppressed deprecation');
+
+    $project->pest('--tia');
+
+    $id = Project::testId('tests/Unit/CalculatorTest.php', 'adds two numbers');
+
+    expect($project->graph()['baselines']['master']['results'][$id]['status'])->toBe(0);
+})->skipOnWindows();

tests/Features/Tia/PartialRunWriteTier.php

@@ -0,0 +1,170 @@
+<?php
+
+declare(strict_types=1);
+
+use Tests\Fixtures\Tia\Project;
+
+afterEach(function (): void {
+    Project::destroyAll();
+});
+
+test('a filtered run rewrites only the test that ran', function (): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $result = $project->pest('--filter=adds two numbers');
+    $delta = $project->delta();
+
+    expect($result->tally())->toContain('1 passed')
+        ->and($result->output)->not->toContain('TIA does not apply to partial runs')
+        ->and($delta->writtenCount())->toBe(1, $delta->summary())
+        ->and($delta->isResultsOnly())->toBeTrue($delta->summary());
+})->skipOnWindows();
+
+test('a filtered run under --tia announces that tia does not apply', function (): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $result = $project->pest('--tia', '--filter=adds two numbers');
+    $delta = $project->delta();
+
+    expect($result->output)->toContain('TIA does not apply to partial runs')
+        ->and($delta->writtenCount())->toBe(1, $delta->summary())
+        ->and($delta->isResultsOnly())->toBeTrue($delta->summary());
+})->skipOnWindows();
+
+test('a test suffix narrows the tier even though every test runs', function (): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $result = $project->pest('--tia', '--test-suffix=Test.php');
+    $delta = $project->delta();
+
+    expect($result->output)->toContain('TIA does not apply to partial runs')
+        ->and($result->tally())->toContain(Project::TOTAL_TESTS.' passed')
+        ->and($delta->writtenCount())->toBe(Project::TOTAL_TESTS, $delta->summary())
+        ->and($delta->isResultsOnly())->toBeTrue($delta->summary());
+})->skipOnWindows();
+
+test('a dirty run narrows to the uncommitted test edit', function (): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->write('tests/Unit/GreeterTest.php', <<<'PHP'
+        <?php
+
+        declare(strict_types=1);
+
+        use Fixture\App\Greeter;
+
+        test('greets a person', function (): void {
+            expect((new Greeter)->greet('Nuno'))->toBe('Hello, Nuno!');
+        });
+
+        test('greets the world', function (): void {
+            expect((new Greeter)->greet('world'))->toBe('Hello, world!');
+        });
+
+        test('greets again', function (): void {
+            expect((new Greeter)->greet('again'))->toBe('Hello, again!');
+        });
+        PHP);
+
+    $result = $project->pest('--tia', '--dirty');
+    $delta = $project->delta();
+
+    expect($result->output)->toContain('TIA does not apply to partial runs')
+        ->and($result->tally())->toContain('3 passed')
+        ->and($delta->removed())->toBe(0, $delta->summary())
+        ->and($delta->structureMoved())->toBeFalse($delta->summary());
+})->skipOnWindows();
+
+test('filtered mode yields to an explicit filter', function (): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $result = $project->pest('--tia', '--filtered', '--filter=adds two numbers');
+    $delta = $project->delta();
+
+    expect($result->output)->toContain('TIA does not apply to partial runs')
+        ->and($result->tally())->toContain('1 passed')
+        ->and($delta->writtenCount())->toBe(1, $delta->summary())
+        ->and($delta->isResultsOnly())->toBeTrue($delta->summary());
+})->skipOnWindows();
+
+test('an env flag narrows exactly like the option it mirrors', function (string $variable): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $result = $project->pestWithEnvironment($project->path(), [
+        $variable => '1',
+    ], '--filter=adds two numbers');
+
+    $delta = $project->delta();
+
+    expect($result->output)->toContain('TIA does not apply to partial runs')
+        ->and($delta->writtenCount())->toBe(1, $delta->summary())
+        ->and($delta->isResultsOnly())->toBeTrue($delta->summary());
+})->with(['PEST_TIA', 'PEST_TIA_FILTERED'])->skipOnWindows();
+
+test('a partial run does not purge the graph even with --fresh', function (): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $result = $project->pest('--tia', '--fresh', '--filter=adds two numbers');
+    $delta = $project->delta();
+
+    expect($result->output)->toContain('TIA does not apply to partial runs')
+        ->and($delta->writtenCount())->toBe(1, $delta->summary())
+        ->and($delta->isResultsOnly())->toBeTrue($delta->summary());
+})->skipOnWindows();
+
+test('--no-tia does not stop a partial run from refreshing its own entry', function (): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $result = $project->pest('--no-tia', '--filter=adds two numbers');
+    $delta = $project->delta();
+
+    expect($result->output)->not->toContain('TIA does not apply to partial runs')
+        ->and($delta->writtenCount())->toBe(1, $delta->summary())
+        ->and($delta->isResultsOnly())->toBeTrue($delta->summary());
+})->skipOnWindows();
+
+test('two partial runs each keep the other entry', function (): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->pest('--filter=adds two numbers');
+    $project->pest('--filter=greets a person');
+
+    $delta = $project->delta();
+
+    expect($delta->writtenCount())->toBe(2, $delta->summary())
+        ->and($delta->isResultsOnly())->toBeTrue($delta->summary());
+})->skipOnWindows();
+
+test('a shard is a partial run', function (): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $result = $project->pest('--tia', '--shard=1/2');
+    $delta = $project->delta();
+
+    expect($result->output)->toContain('TIA does not apply to partial runs')
+        ->and($delta->removed())->toBe(0, $delta->summary())
+        ->and($delta->isResultsOnly())->toBeTrue($delta->summary());
+})->skipOnWindows();
+
+test('a parallel partial run records the test that ran, like a sequential one', function (): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $result = $project->pest('--tia', '--parallel', '--processes=2', '--filter=adds two numbers');
+    $delta = $project->delta();
+
+    expect($result->output)->toContain('TIA does not apply to partial runs')
+        ->and($result->tally())->toContain('1 passed')
+        ->and($delta->writtenCount())->toBe(1, $delta->summary())
+        ->and($delta->isResultsOnly())->toBeTrue($delta->summary());
+})->skipOnWindows();

tests/Features/Tia/RemoteBaseline.php

@@ -0,0 +1,141 @@
+<?php
+
+declare(strict_types=1);
+
+use Tests\Fixtures\Tia\Project;
+
+afterEach(function (): void {
+    Project::destroyAll();
+});
+
+/**
+ * @param  callable(array<string, mixed>): array<string, mixed>|null  $mutator
+ * @return array{0: Project, 1: array<string, string>}
+ */
+function tiaPublishedBaseline(string $mode = 'ok', ?callable $mutator = null): array
+{
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $payload = $project->detachGraph();
+
+    if ($mutator !== null) {
+        /** @var array<string, mixed> $decoded */
+        $decoded = json_decode($payload, true);
+        $payload = (string) json_encode($mutator($decoded), JSON_UNESCAPED_SLASHES);
+    }
+
+    return [$project, $project->gh($mode, $payload)];
+}
+
+test('a published baseline is fetched instead of recorded locally', function (): void {
+    [$project, $environment] = tiaPublishedBaseline();
+
+    $result = $project->pestWithEnvironment($project->path(), $environment, '--tia', '--baselined');
+
+    expect($result->exitCode)->toBe(0, $result->describe())
+        ->and($result->output)->toContain('Downloading TIA baseline')
+        ->and($result->replayed())->toBe(Project::TOTAL_TESTS, $result->describe())
+        ->and($project->graphExists())->toBeTrue();
+})->skipOnWindows();
+
+test('a fetched baseline that will not decode is discarded rather than trusted', function (): void {
+    [$project, $environment] = tiaPublishedBaseline('corrupt');
+
+    $result = $project->pestWithEnvironment($project->path(), $environment, '--tia', '--baselined');
+
+    expect($result->exitCode)->toBe(0, $result->describe())
+        ->and($result->output)->toContain('The dependency graph could not be read')
+        ->and($result->tally())->toContain(Project::TOTAL_TESTS.' passed')
+        ->and($result->replayed())->toBe(0, $result->describe());
+})->skipOnWindows();
+
+test('a fetched baseline recorded against another tree is not used', function (): void {
+    [$project, $environment] = tiaPublishedBaseline('ok', function (array $graph): array {
+        $graph['fingerprint']['structural']['composer_lock'] = 'a-lockfile-this-project-never-had';
+
+        return $graph;
+    });
+
+    $result = $project->pestWithEnvironment($project->path(), $environment, '--tia', '--baselined');
+
+    expect($result->exitCode)->toBe(0, $result->describe())
+        ->and($result->tally())->toContain(Project::TOTAL_TESTS.' passed')
+        ->and($result->replayed())->toBe(0, $result->describe());
+})->skipOnWindows();
+
+test('an artifact without a graph in it fails loudly', function (): void {
+    [$project, $environment] = tiaPublishedBaseline('missing-asset');
+
+    $result = $project->pestWithEnvironment($project->path(), $environment, '--tia', '--baselined');
+
+    expect($result->exitCode)->toBe(1, $result->describe())
+        ->and($result->output)->toContain('the artifact is missing expected files')
+        ->and($project->graphExists())->toBeFalse();
+})->skipOnWindows();
+
+test('a baseline that cannot be authenticated for fails loudly', function (): void {
+    [$project, $environment] = tiaPublishedBaseline('unauthenticated');
+
+    $result = $project->pestWithEnvironment($project->path(), $environment, '--tia', '--baselined');
+
+    expect($result->exitCode)->toBe(1, $result->describe())
+        ->and($result->output)->toContain('is not authenticated')
+        ->and($project->graphExists())->toBeFalse();
+})->skipOnWindows();
+
+test('a workflow or artifact that is not there fails loudly', function (): void {
+    [$project, $environment] = tiaPublishedBaseline('list-404');
+
+    $result = $project->pestWithEnvironment($project->path(), $environment, '--tia', '--baselined');
+
+    expect($result->exitCode)->toBe(1, $result->describe())
+        ->and($result->output)->toContain('not found in repo')
+        ->and($project->graphExists())->toBeFalse();
+})->skipOnWindows();
+
+test('a network failure warns and lets the suite run', function (string $mode): void {
+    [$project, $environment] = tiaPublishedBaseline($mode);
+
+    $result = $project->pestWithEnvironment($project->path(), $environment, '--tia', '--baselined');
+
+    expect($result->exitCode)->toBe(0, $result->describe())
+        ->and($result->output)->toContain('network error')
+        ->and($result->tally())->toContain(Project::TOTAL_TESTS.' passed');
+})->with([
+    'querying the runs' => ['list-network'],
+    'downloading the artifact' => ['download-network'],
+])->skipOnWindows();
+
+test('no published baseline yet starts a cooldown, and a corrupt cooldown does not break the run', function (): void {
+    [$project, $environment] = tiaPublishedBaseline('no-runs');
+
+    $discardGraph = function () use ($project): void {
+        if ($project->graphExists()) {
+            $project->detachGraph();
+        }
+    };
+
+    $first = $project->pestWithEnvironment($project->path(), $environment, '--tia', '--baselined');
+
+    expect($first->exitCode)->toBe(0, $first->describe())
+        ->and($first->output)->toContain('No baseline published yet')
+        ->and($project->graphDir().DIRECTORY_SEPARATOR.'fetch-cooldown.json')->toBeFile();
+
+    $discardGraph();
+
+    $second = $project->pestWithEnvironment($project->path(), $environment, '--tia', '--baselined');
+
+    expect($second->exitCode)->toBe(0, $second->describe())
+        ->and($second->output)->toContain('next auto-retry in');
+
+    file_put_contents($project->graphDir().DIRECTORY_SEPARATOR.'fetch-cooldown.json', 'not json{');
+
+    $discardGraph();
+
+    $third = $project->pestWithEnvironment($project->path(), $environment, '--tia', '--baselined');
+
+    expect($third->exitCode)->toBe(0, $third->describe())
+        ->and($third->output)->toContain('No baseline published yet')
+        ->and($third->tally())->toContain(Project::TOTAL_TESTS.' passed');
+})->skipOnWindows();

tests/Features/Tia/SelectionPaths.php

@@ -0,0 +1,218 @@
+<?php
+
+declare(strict_types=1);
+
+use Tests\Fixtures\Tia\Project;
+
+afterEach(function (): void {
+    Project::destroyAll();
+});
+
+function tiaSeedWithView(Project $project, string $view): void
+{
+    $project->seed('master');
+
+    $project->mutateGraph(function (array $graph) use ($view): array {
+        $id = count($graph['files']);
+        $graph['files'][$id] = $view;
+        $graph['edges']['tests/Unit/GreeterTest.php'][] = $id;
+
+        return $graph;
+    });
+}
+
+/**
+ * @param  array<int, string>  $components
+ * @param  array<string, array<int, string>>  $jsFileToComponents
+ */
+function tiaSeedWithInertia(Project $project, array $components, array $jsFileToComponents = []): void
+{
+    $project->seed('master');
+
+    $project->mutateGraph(function (array $graph) use ($components, $jsFileToComponents): array {
+        $graph['test_inertia_components'] = ['tests/Unit/GreeterTest.php' => $components];
+        $graph['js_file_to_components'] = $jsFileToComponents;
+
+        return $graph;
+    });
+}
+
+test('a committed rename selects the tests that depended on the old path', function (array $arguments): void {
+    $project = Project::make('master');
+    $project->write('resources/views/greeting.blade.php', "<p>Hello</p>\n");
+    $project->git()->commit('add view');
+
+    tiaSeedWithView($project, 'resources/views/greeting.blade.php');
+
+    $project->git()->run(['mv', 'resources/views/greeting.blade.php', 'resources/views/hello.blade.php']);
+    $project->git()->commit('move the view');
+    $project->snapshot();
+
+    $result = $project->pest('--tia', ...$arguments);
+
+    expect($result->exitCode)->toBe(0, $result->describe())
+        ->and($result->affected())->toBe(2, $result->describe())
+        ->and($result->replayed())->toBe(4, $result->describe());
+})->with(Project::SEQUENTIAL_AND_PARALLEL)->skipOnWindows();
+
+test('an affected test file that is gone does not strand a filtered run', function (array $arguments): void {
+    $project = Project::make('master');
+    $project->write('resources/views/page.blade.php', "<p>one</p>\n");
+    $project->git()->commit('add view');
+    $project->seed('master');
+
+    $project->mutateGraph(function (array $graph): array {
+        $id = count($graph['files']);
+        $graph['files'][$id] = 'resources/views/page.blade.php';
+        $graph['edges']['tests/Unit/GhostTest.php'] = [$id];
+
+        return $graph;
+    });
+
+    $project->write('resources/views/page.blade.php', "<p>two</p>\n");
+    $project->snapshot();
+
+    $result = $project->pest('--tia', '--filtered', ...$arguments);
+    $delta = $project->delta();
+
+    expect($result->exitCode)->toBe(0, $result->describe())
+        ->and($result->output)->toContain('No affected tests found')
+        ->and($result->output)->not->toContain('tests/Unit/GhostTest.php')
+        ->and($delta->isHardSuppressed())->toBeTrue($delta->summary());
+})->with(Project::SEQUENTIAL_AND_PARALLEL)->skipOnWindows();
+
+test('a plain run reclaims the edge of a test file that is gone', function (): void {
+    $project = Project::make('master');
+    $project->write('resources/views/page.blade.php', "<p>one</p>\n");
+    $project->git()->commit('add view');
+    $project->seed('master');
+
+    $project->mutateGraph(function (array $graph): array {
+        $id = count($graph['files']);
+        $graph['files'][$id] = 'resources/views/page.blade.php';
+        $graph['edges']['tests/Unit/GhostTest.php'] = [$id];
+        $graph['baselines']['master']['results']['P\\Tests\\Unit\\GhostTest::ghostly'] = [
+            'status' => 0,
+            'message' => '',
+            'time' => 9.999,
+            'assertions' => 42,
+            'file' => 'tests/Unit/GhostTest.php',
+        ];
+
+        return $graph;
+    });
+
+    $project->write('resources/views/page.blade.php', "<p>two</p>\n");
+    $project->snapshot();
+
+    $result = $project->pest('--tia');
+    $delta = $project->delta();
+
+    expect($result->replayed())->toBe(Project::TOTAL_TESTS, $result->describe())
+        ->and($delta->removed())->toBe(1, $delta->summary())
+        ->and($project->graph()['edges'])->not->toHaveKey('tests/Unit/GhostTest.php');
+})->skipOnWindows();
+
+test('a changed view selects the test that rendered it', function (): void {
+    $project = Project::make('master');
+    $project->write('resources/views/page.blade.php', "<p>one</p>\n");
+    $project->git()->commit('add view');
+
+    tiaSeedWithView($project, 'resources/views/page.blade.php');
+
+    $project->write('resources/views/page.blade.php', "<p>two</p>\n");
+    $project->snapshot();
+
+    $result = $project->pest('--tia');
+
+    expect($result->affected())->toBe(2, $result->describe())
+        ->and($result->replayed())->toBe(4, $result->describe());
+})->skipOnWindows();
+
+test('a changed partial selects the test that rendered its ancestor', function (array $views, string $changed): void {
+    $project = Project::make('master');
+
+    foreach ($views as $path => $contents) {
+        $project->write($path, $contents);
+    }
+
+    $project->git()->commit('add views');
+
+    tiaSeedWithView($project, 'resources/views/page.blade.php');
+
+    $project->write($changed, $views[$changed]."<span>edited</span>\n");
+    $project->snapshot();
+
+    $result = $project->pest('--tia');
+
+    expect($result->affected())->toBe(2, $result->describe())
+        ->and($result->replayed())->toBe(4, $result->describe());
+})->with([
+    'direct @include' => [[
+        'resources/views/page.blade.php' => "@include('partials.nav')\n",
+        'resources/views/partials/nav.blade.php' => "<nav>one</nav>\n",
+    ], 'resources/views/partials/nav.blade.php'],
+    'transitive @include' => [[
+        'resources/views/page.blade.php' => "@include('partials.wrapper')\n",
+        'resources/views/partials/wrapper.blade.php' => "@include('partials.nav')\n",
+        'resources/views/partials/nav.blade.php' => "<nav>one</nav>\n",
+    ], 'resources/views/partials/nav.blade.php'],
+    'x- component' => [[
+        'resources/views/page.blade.php' => "<x-card>hi</x-card>\n",
+        'resources/views/components/card.blade.php' => "<div>one</div>\n",
+    ], 'resources/views/components/card.blade.php'],
+    'include cycle' => [[
+        'resources/views/page.blade.php' => "@include('partials.a')\n",
+        'resources/views/partials/a.blade.php' => "@include('partials.b')\n",
+        'resources/views/partials/b.blade.php' => "@include('partials.a')\n",
+    ], 'resources/views/partials/b.blade.php'],
+])->skipOnWindows();
+
+test('a changed Inertia page selects the test that rendered its component', function (): void {
+    $project = Project::make('master');
+    $project->write('resources/js/Pages/Foo.vue', "<template>one</template>\n");
+    $project->git()->commit('add page');
+
+    tiaSeedWithInertia($project, ['Foo']);
+
+    $project->write('resources/js/Pages/Foo.vue', "<template>two</template>\n");
+    $project->snapshot();
+
+    $result = $project->pest('--tia');
+
+    expect($result->affected())->toBe(2, $result->describe())
+        ->and($result->replayed())->toBe(4, $result->describe());
+})->skipOnWindows();
+
+test('a changed shared JS module selects the tests of the pages that import it', function (): void {
+    $project = Project::make('master');
+    $project->write('resources/js/Pages/Foo.vue', "<template>one</template>\n");
+    $project->write('resources/js/Shared/Nav.vue', "<template>nav</template>\n");
+    $project->git()->commit('add pages');
+
+    tiaSeedWithInertia($project, ['Foo'], ['resources/js/Shared/Nav.vue' => ['Foo']]);
+
+    $project->write('resources/js/Shared/Nav.vue', "<template>nav two</template>\n");
+    $project->snapshot();
+
+    $result = $project->pest('--tia');
+
+    expect($result->affected())->toBe(2, $result->describe())
+        ->and($result->replayed())->toBe(4, $result->describe());
+})->skipOnWindows();
+
+test('a changed frontend runtime file selects every Inertia test', function (): void {
+    $project = Project::make('master');
+    $project->write('resources/js/app.js', "console.log(1)\n");
+    $project->git()->commit('add runtime');
+
+    tiaSeedWithInertia($project, ['Foo']);
+
+    $project->write('resources/js/app.js', "console.log(2)\n");
+    $project->snapshot();
+
+    $result = $project->pest('--tia');
+
+    expect($result->affected())->toBe(2, $result->describe())
+        ->and($result->replayed())->toBe(4, $result->describe());
+})->skipOnWindows();

tests/Features/Tia/StateReclamation.php

@@ -0,0 +1,360 @@
+<?php
+
+declare(strict_types=1);
+
+use Tests\Fixtures\Tia\Project;
+
+afterEach(function (): void {
+    Project::destroyAll();
+});
+
+test('a detached HEAD does not purge the graph on structural drift', function (array $arguments): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->git()->detach();
+
+    $project->write('composer.lock', (string) json_encode([
+        'content-hash' => 'drifted',
+        'packages' => [],
+        'packages-dev' => [],
+    ]));
+
+    $result = $project->pest('--tia', ...$arguments);
+    $delta = $project->delta();
+
+    expect($result->exitCode)->toBe(0, $result->describe())
+        ->and($project->graphExists())->toBeTrue('the detached run deleted graph.json')
+        ->and($delta->isHardSuppressed())->toBeTrue($delta->summary());
+})->with(Project::SEQUENTIAL_AND_PARALLEL)->skipOnWindows();
+
+test('a detached HEAD does not purge the graph with --fresh either', function (array $arguments): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->git()->detach();
+
+    $result = $project->pest('--tia', '--fresh', ...$arguments);
+    $delta = $project->delta();
+
+    expect($result->exitCode)->toBe(0, $result->describe())
+        ->and($project->graphExists())->toBeTrue('the detached --fresh run deleted graph.json')
+        ->and($delta->isHardSuppressed())->toBeTrue($delta->summary());
+})->with(Project::SEQUENTIAL_AND_PARALLEL)->skipOnWindows();
+
+test('a detached HEAD leaves an unreadable graph for a checkout that can rebuild it', function (): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->git()->detach();
+
+    file_put_contents($project->graphDir().'/graph.json', '{not json');
+
+    $result = $project->pest('--tia');
+
+    expect($result->exitCode)->toBe(0, $result->describe())
+        ->and($result->tally())->toContain(Project::TOTAL_TESTS.' passed')
+        ->and(file_get_contents($project->graphDir().'/graph.json'))->toBe('{not json');
+})->skipOnWindows();
+
+test('a cached failure whose test file was deleted stops widening later runs', function (array $arguments): void {
+    $project = Project::make('master');
+    $project->seed('master', failing: ['adds two numbers']);
+
+    unlink($project->path('tests/Unit/CalculatorTest.php'));
+    $project->git()->commit('drop CalculatorTest');
+
+    $project->pest('--tia', '--filtered', ...$arguments);
+
+    $project->snapshot();
+    $second = $project->pest('--tia', '--filtered', ...$arguments);
+    $delta = $project->delta();
+
+    expect($second->output)->not->toContain('could not be located on disk')
+        ->and($second->output)->toContain('No affected tests found')
+        ->and($delta->isHardSuppressed())->toBeTrue($delta->summary());
+})->with(Project::SEQUENTIAL_AND_PARALLEL)->skipOnWindows();
+
+test('a complete run reclaims the entry and the edge of a deleted test file', function (array $arguments): void {
+    $project = Project::make('master');
+    $project->seed('master', failing: ['adds two numbers']);
+
+    unlink($project->path('tests/Unit/CalculatorTest.php'));
+    $project->git()->commit('drop CalculatorTest');
+
+    $project->pest('--tia', ...$arguments);
+
+    $graph = $project->graph();
+
+    expect($graph['edges'] ?? [])->not->toHaveKey('tests/Unit/CalculatorTest.php')
+        ->and(array_column($graph['baselines']['master']['results'] ?? [], 'file'))
+        ->not->toContain('tests/Unit/CalculatorTest.php');
+})->with(Project::SEQUENTIAL_AND_PARALLEL)->skipOnWindows();
+
+test('a pruned result does not come back from the fallback', function (array $arguments): void {
+    $project = Project::make('master');
+    $project->seed('master', failing: ['adds two numbers']);
+
+    $project->git()->switchTo('feature-x', new: true);
+
+    $project->write('tests/Unit/CalculatorTest.php', <<<'PHP'
+    <?php
+
+    declare(strict_types=1);
+
+    use Fixture\App\Calculator;
+
+    test('adds two numbers, renamed', function (): void {
+        expect((new Calculator)->add(1, 2))->toBe(3);
+    });
+
+    test('subtracts two numbers', function (): void {
+        expect((new Calculator)->subtract(3, 1))->toBe(2);
+    });
+    PHP);
+
+    $project->git()->commit('rename the test on the branch');
+
+    $project->pest('--tia', '--filtered', ...$arguments);
+
+    $second = $project->pest('--tia', '--filtered', ...$arguments);
+
+    expect($second->output)->not->toContain('previously unsuccessful')
+        ->and($second->output)->toContain('No affected tests found');
+})->with(Project::SEQUENTIAL_AND_PARALLEL)->skipOnWindows();
+
+test('the fallback still reaches a branch that has never run a test file', function (): void {
+    $project = Project::make('master');
+    $project->seed('master', failing: ['adds two numbers']);
+
+    $project->git()->switchTo('feature-x', new: true);
+
+    $project->pest('--filter=greets a person');
+
+    $result = $project->pest('--tia', '--filtered');
+
+    expect($result->output)->toContain('previously unsuccessful')
+        ->and($result->affected())->toBe(2, $result->describe());
+})->skipOnWindows();
+
+test('a branch that git no longer knows loses its baseline', function (): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->git()->switchTo('feature-x', new: true);
+    $project->pest('--tia');
+
+    expect($project->branchKeys())->toBe(['master', 'feature-x']);
+
+    $project->git()->switchTo('master');
+    $project->git()->run(['branch', '-D', 'feature-x']);
+
+    $project->pest('--tia');
+
+    expect($project->branchKeys())->toBe(['master']);
+})->skipOnWindows();
+
+test('an unknown cached status is re-run rather than replayed as a failure', function (int $status): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->mutateGraph(function (array $graph) use ($status): array {
+        $id = Project::testId('tests/Unit/CalculatorTest.php', 'adds two numbers');
+        $graph['baselines']['master']['results'][$id]['status'] = $status;
+
+        return $graph;
+    });
+
+    $result = $project->pest('--tia');
+
+    expect($result->exitCode)->toBe(0, $result->describe())
+        ->and($result->tally())->toContain(Project::TOTAL_TESTS.' passed')
+        ->and($result->uncached())->toBe(1, $result->describe());
+})->with(['unknown' => -1, 'future' => 9, 'garbage' => 99])->skipOnWindows();
+
+test('a cached notice, deprecation or warning does not replay as a failure', function (int $status): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->mutateGraph(function (array $graph) use ($status): array {
+        $id = Project::testId('tests/Unit/CalculatorTest.php', 'adds two numbers');
+        $graph['baselines']['master']['results'][$id]['status'] = $status;
+        $graph['baselines']['master']['results'][$id]['message'] = 'cached detail';
+
+        return $graph;
+    });
+
+    $result = $project->pest('--tia');
+
+    expect($result->exitCode)->toBe(0, $result->describe())
+        ->and($result->tally())->toContain(Project::TOTAL_TESTS.' passed');
+})->with(['notice' => 3, 'deprecation' => 4, 'warning' => 6])->skipOnWindows();
+
+test('a malformed baseline entry cannot break the run', function (array $arguments): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->mutateGraph(function (array $graph): array {
+        $id = Project::testId('tests/Unit/CalculatorTest.php', 'adds two numbers');
+        $graph['baselines']['master']['results'][$id] = 'nope';
+        $graph['baselines']['master']['tree'] = 'nope';
+        $graph['edges']['tests/Unit/GreeterTest.php'] = 'nope';
+
+        return $graph;
+    });
+
+    $result = $project->pest('--tia', ...$arguments);
+
+    expect($result->exitCode)->toBe(0, $result->describe())
+        ->and($result->output)->not->toContain('TypeError')
+        ->and($result->tally())->toContain(Project::TOTAL_TESTS.' passed');
+})->with(Project::SEQUENTIAL_AND_PARALLEL)->skipOnWindows();
+
+test('a run torn down mid-file does not prune the tests it never reached', function (array $arguments): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->write('tests/Unit/CalculatorTest.php', <<<'PHP'
+    <?php
+
+    declare(strict_types=1);
+
+    use Fixture\App\Calculator;
+
+    test('adds two numbers', function (): void {
+        expect((new Calculator)->add(1, 2))->toBe(3);
+    });
+
+    test('subtracts two numbers', function (): void {
+        exit(0);
+    });
+    PHP);
+
+    $project->git()->commit('a test that kills its own process');
+
+    $project->pest('--tia', ...$arguments);
+    $delta = $project->delta();
+
+    expect($delta->removed())->toBe(0, $delta->summary())
+        ->and($delta->shaMoved())->toBeFalse($delta->summary())
+        ->and($delta->structureMoved())->toBeFalse($delta->summary())
+        ->and(array_keys($project->graph()['baselines']['master']['results']))
+        ->toContain(Project::testId('tests/Unit/CalculatorTest.php', 'subtracts two numbers'));
+})->with(Project::SEQUENTIAL_AND_PARALLEL)->skipOnWindows();
+
+test('a fatal error mid-file is a test error, not a truncation', function (array $arguments): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->write('tests/Unit/CalculatorTest.php', <<<'PHP'
+    <?php
+
+    declare(strict_types=1);
+
+    use Fixture\App\Calculator;
+
+    test('adds two numbers', function (): void {
+        expect((new Calculator)->add(1, 2))->toBe(3);
+    });
+
+    test('subtracts two numbers', function (): void {
+        undefined_function_here();
+    });
+    PHP);
+
+    $project->git()->commit('a test that fatals');
+
+    $result = $project->pest('--tia', ...$arguments);
+    $delta = $project->delta();
+
+    expect($result->exitCode)->not->toBe(0)
+        ->and($result->tally())->toContain('1 failed')
+        ->and($delta->removed())->toBe(0, $delta->summary())
+        ->and($delta->structureMoved())->toBeFalse($delta->summary());
+})->with(Project::SEQUENTIAL_AND_PARALLEL)->skipOnWindows();
+
+test('a green complete run leaves the graph exactly as it found it', function (array $arguments): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $result = $project->pest('--tia', ...$arguments);
+    $delta = $project->delta();
+
+    expect($result->replayed())->toBe(Project::TOTAL_TESTS, $result->describe())
+        ->and($delta->isHardSuppressed())->toBeTrue($delta->summary());
+})->with([
+    'bail' => [['--bail']],
+    'stop-on-failure' => [['--stop-on-failure']],
+    'compact' => [['--compact']],
+    'parallel bail' => [['--parallel', '--processes=2', '--bail']],
+    'parallel one process' => [['--parallel', '--processes=1']],
+    'parallel more processes than files' => [['--parallel', '--processes=8']],
+])->skipOnWindows();
+
+test('--tia --no-tia is a plain run that still refreshes what it executed', function (array $arguments): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $result = $project->pest('--tia', '--no-tia', ...$arguments);
+    $delta = $project->delta();
+
+    expect($result->replayed())->toBe(0, $result->describe())
+        ->and($result->tally())->toContain(Project::TOTAL_TESTS.' passed')
+        ->and($delta->writtenCount())->toBe(Project::TOTAL_TESTS, $delta->summary())
+        ->and($delta->isResultsOnly())->toBeTrue($delta->summary());
+})->with(Project::SEQUENTIAL_AND_PARALLEL)->skipOnWindows();
+
+test('--fresh on a partial run neither purges nor prunes', function (array $arguments): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $result = $project->pest('--tia', '--fresh', '--filter=adds two numbers', ...$arguments);
+    $delta = $project->delta();
+
+    expect($result->exitCode)->toBe(0, $result->describe())
+        ->and($project->graphExists())->toBeTrue()
+        ->and($delta->writtenCount())->toBe(1, $delta->summary())
+        ->and($delta->isResultsOnly())->toBeTrue($delta->summary());
+})->with(Project::SEQUENTIAL_AND_PARALLEL)->skipOnWindows();
+
+test('a second green run on a feature branch writes nothing at all', function (array $arguments): void {
+    $project = Project::make('master');
+    $project->seed('master');
+
+    $project->git()->switchTo('feature-x', new: true);
+    $project->pest('--tia', ...$arguments);
+
+    $project->snapshot();
+    $result = $project->pest('--tia', ...$arguments);
+    $delta = $project->delta();
+
+    expect($result->replayed())->toBe(Project::TOTAL_TESTS, $result->describe())
+        ->and($delta->isHardSuppressed())->toBeTrue($delta->summary());
+})->with(Project::SEQUENTIAL_AND_PARALLEL)->skipOnWindows();
+
+test('a graph whose recorded commit is gone is re-anchored, not warned about forever', function (array $arguments): void {
+    $project = Project::make('master');
+    $project->git()->commit('second');
+    $project->seed('master');
+
+    $recordedSha = $project->graph()['baselines']['master']['sha'];
+
+    $project->git()->run(['reset', '--quiet', '--hard', 'HEAD~1']);
+    $project->snapshot();
+
+    $first = $project->pest('--tia', ...$arguments);
+
+    expect($first->exitCode)->toBe(0, $first->describe())
+        ->and($first->output)->toContain('no longer reachable')
+        ->and($first->tally())->toContain(Project::TOTAL_TESTS.' passed')
+        ->and($project->graph()['baselines']['master']['sha'])->not->toBe($recordedSha)
+        ->and($project->graph()['baselines']['master']['sha'])->toBe($project->git()->sha());
+
+    $project->snapshot();
+    $second = $project->pest('--tia', ...$arguments);
+    $delta = $project->delta();
+
+    expect($second->output)->not->toContain('no longer reachable')
+        ->and($second->replayed())->toBe(Project::TOTAL_TESTS, $second->describe())
+        ->and($delta->writtenCount())->toBe(0, $delta->summary());
+})->with(Project::SEQUENTIAL_AND_PARALLEL)->skipOnWindows();

tests/Fixtures/Suites/InvalidNames/2fa/login.test.php

@@ -0,0 +1,5 @@
+<?php
+
+// The folder name creates the namespace segment `2fa`, which starts with a number.
+
+it('never runs')->assertTrue(true);

tests/Fixtures/Suites/InvalidNames/ReservedKeyword/list.test.php

@@ -0,0 +1,5 @@
+<?php
+
+// The file name creates the class `list`, which is a PHP keyword.
+
+it('never runs')->assertTrue(true);

tests/Fixtures/Suites/InvalidNames/ReservedType/int.test.php

@@ -0,0 +1,5 @@
+<?php
+
+// The file name creates the class `int`, which is a name PHP reserves.
+
+it('never runs')->assertTrue(true);

tests/Fixtures/Suites/InvalidNames/StartsWithNumber/2fa.test.php

@@ -0,0 +1,5 @@
+<?php
+
+// The file name creates the class `2fa`, which starts with a number.
+
+it('never runs')->assertTrue(true);

tests/Fixtures/Suites/MultipleGroups/OneTest.php

@@ -0,0 +1,5 @@
+<?php
+
+it('belongs to group one', function () {
+    expect(true)->toBeTrue();
+})->group('one');

tests/Fixtures/Suites/MultipleGroups/ThreeTest.php

@@ -0,0 +1,5 @@
+<?php
+
+it('belongs to group three', function () {
+    expect(true)->toBeTrue();
+})->group('three');

tests/Fixtures/Suites/MultipleGroups/TwoTest.php

@@ -0,0 +1,5 @@
+<?php
+
+it('belongs to group two', function () {
+    expect(true)->toBeTrue();
+})->group('two');

tests/Fixtures/Suites/TiaReplayHooks.php

@@ -0,0 +1,24 @@
+<?php
+
+// Only ever run through `tests/Features/Tia.php`, against a seeded TIA graph.
+// Both hooks throw, so a replayed test that wrongly runs one fails the run.
+
+beforeEach(function (): void {
+    throw new RuntimeException('The beforeEach hook must not run for replayed tests.');
+});
+
+afterEach(function (): void {
+    throw new RuntimeException('The afterEach hook must not run for replayed tests.');
+});
+
+test('replayed pass', function (): void {
+    expect(true)->toBeTrue();
+});
+
+test('replayed skip', function (): void {
+    expect(true)->toBeTrue();
+});
+
+test('replayed incomplete', function (): void {
+    expect(true)->toBeTrue();
+});

tests/Fixtures/Suites/TiaReplayHooks.xml

@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+  Runs TiaReplayHooks.php as a suite of its own, so `tests/Features/Tia.php` can
+  replay it without narrowing the run to a path. TIA declines to replay a
+  narrowed run, and a single-file invocation is exactly that.
+-->
+<phpunit xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:noNamespaceSchemaLocation="https://schema.phpunit.de/10.0/phpunit.xsd"
+         bootstrap="../../../vendor/autoload.php"
+         colors="true"
+>
+  <testsuites>
+    <testsuite name="default">
+      <file>TiaReplayHooks.php</file>
+    </testsuite>
+  </testsuites>
+</phpunit>

tests/Fixtures/Tia/GitRepo.php

@@ -0,0 +1,147 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Tests\Fixtures\Tia;
+
+use RuntimeException;
+use Symfony\Component\Process\Process;
+
+/**
+ * @internal
+ */
+final readonly class GitRepo
+{
+    /**
+     * @var array<string, string>
+     */
+    public const array ENV = [
+        'GIT_CONFIG_GLOBAL' => '/dev/null',
+        'GIT_CONFIG_SYSTEM' => '/dev/null',
+        'GIT_CONFIG_NOSYSTEM' => '1',
+        'GIT_AUTHOR_NAME' => 'Pest Fixture',
+        'GIT_AUTHOR_EMAIL' => 'fixture@pestphp.io',
+        'GIT_COMMITTER_NAME' => 'Pest Fixture',
+        'GIT_COMMITTER_EMAIL' => 'fixture@pestphp.io',
+    ];
+
+    public function __construct(public string $path) {}
+
+    public function init(string $branch = 'master'): void
+    {
+        $this->run(['init', '--quiet']);
+        $this->run(['checkout', '--quiet', '-b', $branch]);
+        $this->commit('Initial commit');
+    }
+
+    public function commit(string $message): void
+    {
+        $this->run(['add', '-A']);
+        $this->run(['commit', '--quiet', '--allow-empty', '-m', $message]);
+    }
+
+    public function switchTo(string $branch, bool $new = false): void
+    {
+        $this->run($new ? ['checkout', '--quiet', '-b', $branch] : ['checkout', '--quiet', $branch]);
+    }
+
+    public function rename(string $from, string $to): void
+    {
+        $this->run(['branch', '-m', $from, $to]);
+    }
+
+    public function detach(): void
+    {
+        $this->run(['checkout', '--quiet', '--detach']);
+    }
+
+    public function addOrigin(string $url = 'git@github.com:pestphp/tia-fixture.git'): void
+    {
+        $this->run(['remote', 'add', 'origin', $url]);
+    }
+
+    public function removeOrigin(): void
+    {
+        $this->run(['remote', 'remove', 'origin']);
+    }
+
+    public function setOriginHead(string $branch): void
+    {
+        $this->run(['update-ref', 'refs/remotes/origin/'.$branch, 'HEAD']);
+        $this->run(['symbolic-ref', 'refs/remotes/origin/HEAD', 'refs/remotes/origin/'.$branch]);
+    }
+
+    public function unsetOriginHead(): void
+    {
+        $this->run(['symbolic-ref', '--delete', 'refs/remotes/origin/HEAD']);
+    }
+
+    public function config(string $key, string $value): void
+    {
+        $this->run(['config', '--local', $key, $value]);
+    }
+
+    public function worktree(string $path, string $branch): string
+    {
+        $this->run(['worktree', 'add', '--quiet', '-b', $branch, $path]);
+
+        return $path;
+    }
+
+    public function sha(): string
+    {
+        return $this->output(['rev-parse', 'HEAD']);
+    }
+
+    public function currentBranch(): string
+    {
+        return $this->output(['rev-parse', '--abbrev-ref', 'HEAD']);
+    }
+
+    /**
+     * @return array<int, string>
+     */
+    public function branchNames(): array
+    {
+        $names = explode("\n", $this->output(['for-each-ref', '--format=%(refname:short)', 'refs/heads']));
+
+        return array_values(array_filter($names, fn (string $name): bool => $name !== ''));
+    }
+
+    /**
+     * @param  array<int, string>  $arguments
+     */
+    public function output(array $arguments): string
+    {
+        return trim($this->process($arguments, mustSucceed: true)->getOutput());
+    }
+
+    /**
+     * @param  array<int, string>  $arguments
+     */
+    public function run(array $arguments): void
+    {
+        $this->process($arguments, mustSucceed: true);
+    }
+
+    /**
+     * @param  array<int, string>  $arguments
+     */
+    private function process(array $arguments, bool $mustSucceed): Process
+    {
+        $process = new Process(['git', ...$arguments], $this->path, self::ENV);
+        $process->setTimeout(120.0);
+        $process->run();
+
+        if ($mustSucceed && ! $process->isSuccessful()) {
+            throw new RuntimeException(sprintf(
+                "git %s failed in [%s]:\n%s",
+                implode(' ', $arguments),
+                $this->path,
+                $process->getErrorOutput().$process->getOutput(),
+            ));
+        }
+
+        return $process;
+    }
+}

tests/Fixtures/Tia/GraphDelta.php

@@ -0,0 +1,293 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Tests\Fixtures\Tia;
+
+/**
+ * @internal
+ */
+final readonly class GraphDelta
+{
+    /**
+     * @param  array<string, mixed>|null  $before
+     * @param  array<string, mixed>|null  $after
+     */
+    public function __construct(
+        private ?array $before,
+        private ?array $after,
+    ) {}
+
+    public function graphWasCreated(): bool
+    {
+        return $this->before === null && $this->after !== null;
+    }
+
+    public function graphWasDeleted(): bool
+    {
+        return $this->before !== null && $this->after === null;
+    }
+
+    public function writtenCount(): int
+    {
+        $written = 0;
+
+        foreach ($this->branchKeys() as $branch) {
+            $before = $this->results($this->before, $branch);
+            $after = $this->results($this->after, $branch);
+
+            foreach ($before as $testId => $entry) {
+                if (! isset($after[$testId])) {
+                    continue;
+                }
+
+                foreach (['status', 'time', 'assertions', 'message'] as $field) {
+                    if (($entry[$field] ?? null) !== ($after[$testId][$field] ?? null)) {
+                        $written++;
+
+                        break;
+                    }
+                }
+            }
+        }
+
+        return $written;
+    }
+
+    public function added(): int
+    {
+        $added = 0;
+
+        foreach ($this->branchKeys() as $branch) {
+            $added += count(array_diff(
+                array_keys($this->results($this->after, $branch)),
+                array_keys($this->results($this->before, $branch)),
+            ));
+        }
+
+        return $added;
+    }
+
+    public function removed(): int
+    {
+        $removed = 0;
+
+        foreach ($this->branchKeys() as $branch) {
+            $removed += count(array_diff(
+                array_keys($this->results($this->before, $branch)),
+                array_keys($this->results($this->after, $branch)),
+            ));
+        }
+
+        return $removed;
+    }
+
+    /**
+     * @return array<int, string>
+     */
+    public function branchKeys(): array
+    {
+        return array_map(strval(...), array_keys($this->baselines($this->after)));
+    }
+
+    /**
+     * @return array<int, string>
+     */
+    public function branchKeysBefore(): array
+    {
+        return array_map(strval(...), array_keys($this->baselines($this->before)));
+    }
+
+    public function branchKeysMoved(): bool
+    {
+        return $this->branchKeysBefore() !== $this->branchKeys();
+    }
+
+    public function baselineUntouched(string $branch): bool
+    {
+        return ($this->baselines($this->before)[$branch] ?? null)
+            === ($this->baselines($this->after)[$branch] ?? null);
+    }
+
+    public function shaMoved(): bool
+    {
+        return array_any($this->branchKeys(), fn (string $branch) => $this->baselineField($branch, 'sha', $this->before) !== $this->baselineField($branch, 'sha', $this->after));
+    }
+
+    public function treeMoved(): bool
+    {
+        return array_any($this->branchKeys(), fn (string $branch) => $this->baselineField($branch, 'tree', $this->before) !== $this->baselineField($branch, 'tree', $this->after));
+    }
+
+    public function edgesMoved(): bool
+    {
+        return $this->edgeSets($this->before) !== $this->edgeSets($this->after);
+    }
+
+    public function filesMoved(): bool
+    {
+        return $this->section($this->before, 'files') !== $this->section($this->after, 'files');
+    }
+
+    public function fingerprintMoved(): bool
+    {
+        return $this->section($this->before, 'fingerprint') !== $this->section($this->after, 'fingerprint');
+    }
+
+    public function structureMoved(): bool
+    {
+        if ($this->edgesMoved()) {
+            return true;
+        }
+        if ($this->filesMoved()) {
+            return true;
+        }
+        if ($this->fingerprintMoved()) {
+            return true;
+        }
+
+        return $this->branchKeysMoved();
+    }
+
+    public function isHardSuppressed(): bool
+    {
+        return $this->before === $this->after;
+    }
+
+    public function isResultsOnly(): bool
+    {
+        return ! $this->graphWasCreated()
+            && ! $this->graphWasDeleted()
+            && ! $this->structureMoved()
+            && ! $this->shaMoved()
+            && ! $this->treeMoved()
+            && $this->removed() === 0
+            && $this->added() === 0;
+    }
+
+    public function summary(): string
+    {
+        if ($this->graphWasCreated()) {
+            return 'graph created';
+        }
+
+        if ($this->graphWasDeleted()) {
+            return 'graph deleted';
+        }
+
+        $moved = [];
+
+        foreach (['edges', 'files', 'fingerprint'] as $section) {
+            if ($this->{$section.'Moved'}()) {
+                $moved[] = $section;
+            }
+        }
+
+        if ($this->branchKeysMoved()) {
+            $moved[] = sprintf(
+                'branchkeys(%s->%s)',
+                implode('|', $this->branchKeysBefore()),
+                implode('|', $this->branchKeys()),
+            );
+        }
+
+        return sprintf(
+            'w=%d +%d -%d %s%s%s',
+            $this->writtenCount(),
+            $this->added(),
+            $this->removed(),
+            $moved === [] ? 'struct:ok' : 'STRUCT:'.implode(',', $moved),
+            $this->shaMoved() ? ' sha:changed' : '',
+            $this->treeMoved() ? ' tree:changed' : '',
+        );
+    }
+
+    /**
+     * @param  array<string, mixed>|null  $graph
+     * @return array<string, array<int, string>>
+     */
+    private function edgeSets(?array $graph): array
+    {
+        $files = $this->section($graph, 'files');
+        $sets = [];
+
+        foreach ($this->section($graph, 'edges') as $test => $ids) {
+            if (! is_string($test)) {
+                continue;
+            }
+            if (! is_array($ids)) {
+                continue;
+            }
+            $paths = array_map(
+                fn (mixed $id): string => is_int($id) && isset($files[$id]) && is_string($files[$id])
+                    ? $files[$id]
+                    : '?'.json_encode($id),
+                $ids,
+            );
+
+            sort($paths);
+            $sets[$test] = $paths;
+        }
+
+        ksort($sets);
+
+        return $sets;
+    }
+
+    /**
+     * @param  array<string, mixed>|null  $graph
+     * @return array<mixed>
+     */
+    private function section(?array $graph, string $key): array
+    {
+        $section = $graph[$key] ?? null;
+
+        return is_array($section) ? $section : [];
+    }
+
+    /**
+     * @param  array<string, mixed>|null  $graph
+     * @return array<string, mixed>
+     */
+    private function baselines(?array $graph): array
+    {
+        $baselines = [];
+
+        foreach ($this->section($graph, 'baselines') as $branch => $baseline) {
+            $baselines[(string) $branch] = $baseline;
+        }
+
+        return $baselines;
+    }
+
+    /**
+     * @param  array<string, mixed>|null  $graph
+     * @return array<string, array<string, mixed>>
+     */
+    private function results(?array $graph, string $branch): array
+    {
+        $results = $this->baselines($graph)[$branch]['results'] ?? null;
+
+        if (! is_array($results)) {
+            return [];
+        }
+
+        $entries = [];
+
+        foreach ($results as $testId => $entry) {
+            if (is_string($testId) && is_array($entry)) {
+                $entries[$testId] = $entry;
+            }
+        }
+
+        return $entries;
+    }
+
+    /**
+     * @param  array<string, mixed>|null  $graph
+     */
+    private function baselineField(string $branch, string $field, ?array $graph): mixed
+    {
+        return $this->baselines($graph)[$branch][$field] ?? null;
+    }
+}