feat(tia): continues to work on poc

src/Plugins/Tia/CachedTestResult.php

@@ -0,0 +1,33 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Pest\Plugins\Tia;
+
+/**
+ * Immutable snapshot of a previous test run's outcome. Stored in the TIA
+ * graph and returned by `BeforeEachable::beforeEach` so `Testable` can
+ * faithfully replay the exact status — pass, fail, skip, todo, incomplete,
+ * risky, etc. — without executing the test body.
+ *
+ * @internal
+ */
+final readonly class CachedTestResult
+{
+    /**
+     * PHPUnit TestStatus int constants:
+     *   0 = success, 1 = skipped, 2 = incomplete,
+     *   3 = notice, 4 = deprecation, 5 = risky,
+     *   6 = warning, 7 = failure, 8 = error.
+     */
+    public function __construct(
+        public int $status,
+        public string $message = '',
+        public float $time = 0.0,
+    ) {}
+
+    public function isSuccess(): bool
+    {
+        return $this->status === 0;
+    }
+}

src/Plugins/Tia/ChangedFiles.php

@@ -32,6 +32,84 @@ final readonly class ChangedFiles
      *                                 from HEAD (rebase / force-push) — in
      *                                 that case the graph should be rebuilt.
      */
+    /**
+     * Removes files whose current content hash matches the snapshot from the
+     * last `--tia` run. Used to ignore "dirty but unchanged" files — a file
+     * that git still reports as modified but whose content is bit-identical
+     * to the previous TIA invocation.
+     *
+     * @param  array<int, string>  $files          project-relative paths.
+     * @param  array<string, string>  $lastRunTree  path → content hash from last run.
+     * @return array<int, string>
+     */
+    public function filterUnchangedSinceLastRun(array $files, array $lastRunTree): array
+    {
+        if ($lastRunTree === []) {
+            return $files;
+        }
+
+        $remaining = [];
+
+        foreach ($files as $file) {
+            if (! isset($lastRunTree[$file])) {
+                $remaining[] = $file;
+
+                continue;
+            }
+
+            $absolute = $this->projectRoot.DIRECTORY_SEPARATOR.$file;
+
+            if (! is_file($absolute)) {
+                // File deleted since last run — definitely changed.
+                $remaining[] = $file;
+
+                continue;
+            }
+
+            $hash = @hash_file('xxh128', $absolute);
+
+            if ($hash === false || $hash !== $lastRunTree[$file]) {
+                $remaining[] = $file;
+            }
+        }
+
+        return $remaining;
+    }
+
+    /**
+     * Computes content hashes for the given project-relative files. Used to
+     * snapshot the working tree after a successful run so the next run can
+     * detect which files are actually different.
+     *
+     * @param  array<int, string>  $files
+     * @return array<string, string>  path → xxh128 content hash
+     */
+    public function snapshotTree(array $files): array
+    {
+        $out = [];
+
+        foreach ($files as $file) {
+            $absolute = $this->projectRoot.DIRECTORY_SEPARATOR.$file;
+
+            if (! is_file($absolute)) {
+                continue;
+            }
+
+            $hash = @hash_file('xxh128', $absolute);
+
+            if ($hash !== false) {
+                $out[$file] = $hash;
+            }
+        }
+
+        return $out;
+    }
+
+    /**
+     * @return array<int, string>|null `null` when git is unavailable, or when
+     *                                 the recorded SHA is no longer reachable
+     *                                 from HEAD (rebase / force-push).
+     */
     public function since(?string $sha): ?array
     {
         if (! $this->gitAvailable()) {
@@ -87,6 +165,24 @@ final readonly class ChangedFiles
         return false;
     }
 
+    public function currentBranch(): ?string
+    {
+        if (! $this->gitAvailable()) {
+            return null;
+        }
+
+        $process = new Process(['git', 'rev-parse', '--abbrev-ref', 'HEAD'], $this->projectRoot);
+        $process->run();
+
+        if (! $process->isSuccessful()) {
+            return null;
+        }
+
+        $branch = trim($process->getOutput());
+
+        return $branch === '' || $branch === 'HEAD' ? null : $branch;
+    }
+
     public function gitAvailable(): bool
     {
         $process = new Process(['git', 'rev-parse', '--git-dir'], $this->projectRoot);

src/Plugins/Tia/Graph.php

@@ -47,9 +47,22 @@ final class Graph
     private array $fingerprint = [];
 
     /**
-     * Commit SHA the graph was recorded against (if in a git repo).
+     * Per-branch baselines. Each branch independently tracks:
+     *   - `sha`     — last HEAD at which `--tia` ran on this branch
+     *   - `tree`    — content hashes of modified files at that point
+     *   - `results` — per-test status + message + time
+     *
+     * Graph edges (test → source) stay shared across branches because
+     * structure doesn't change per branch. Only run-state is per-branch so
+     * a failing test on one branch doesn't poison another branch's replay.
+     *
+     * @var array<string, array{
+     *     sha: ?string,
+     *     tree: array<string, string>,
+     *     results: array<string, array{status: int, message: string, time: float}>
+     * }>
      */
-    private ?string $recordedAtSha = null;
+    private array $baselines = [];
 
     /**
      * Canonicalised project root. Resolved through `realpath()` so paths
@@ -224,14 +237,84 @@ final class Graph
         return $this->fingerprint;
     }
 
-    public function setRecordedAtSha(?string $sha): void
+    /**
+     * Returns the SHA the given branch last ran against, or falls back to
+     * `$fallbackBranch` (typically `main`) when this branch has no baseline
+     * yet. That way a freshly-created feature branch inherits main's
+     * baseline on its first run.
+     */
+    public function recordedAtSha(string $branch, string $fallbackBranch = 'main'): ?string
     {
-        $this->recordedAtSha = $sha;
+        $baseline = $this->baselineFor($branch, $fallbackBranch);
+
+        return $baseline['sha'];
     }
 
-    public function recordedAtSha(): ?string
+    public function setRecordedAtSha(string $branch, ?string $sha): void
     {
-        return $this->recordedAtSha;
+        $this->ensureBaseline($branch);
+        $this->baselines[$branch]['sha'] = $sha;
+    }
+
+    public function setResult(string $branch, string $testId, int $status, string $message, float $time): void
+    {
+        $this->ensureBaseline($branch);
+        $this->baselines[$branch]['results'][$testId] = [
+            'status' => $status, 'message' => $message, 'time' => $time,
+        ];
+    }
+
+    public function getResult(string $branch, string $testId, string $fallbackBranch = 'main'): ?CachedTestResult
+    {
+        $baseline = $this->baselineFor($branch, $fallbackBranch);
+
+        if (! isset($baseline['results'][$testId])) {
+            return null;
+        }
+
+        $r = $baseline['results'][$testId];
+
+        return new CachedTestResult($r['status'], $r['message'], $r['time']);
+    }
+
+    /**
+     * @param  array<string, string>  $tree  project-relative path → content hash
+     */
+    public function setLastRunTree(string $branch, array $tree): void
+    {
+        $this->ensureBaseline($branch);
+        $this->baselines[$branch]['tree'] = $tree;
+    }
+
+    /**
+     * @return array<string, string>
+     */
+    public function lastRunTree(string $branch, string $fallbackBranch = 'main'): 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}>}
+     */
+    private function baselineFor(string $branch, string $fallbackBranch): array
+    {
+        if (isset($this->baselines[$branch])) {
+            return $this->baselines[$branch];
+        }
+
+        if ($branch !== $fallbackBranch && isset($this->baselines[$fallbackBranch])) {
+            return $this->baselines[$fallbackBranch];
+        }
+
+        return ['sha' => null, 'tree' => [], 'results' => []];
+    }
+
+    private function ensureBaseline(string $branch): void
+    {
+        if (! isset($this->baselines[$branch])) {
+            $this->baselines[$branch] = ['sha' => null, 'tree' => [], 'results' => []];
+        }
     }
 
     /**
@@ -296,10 +379,10 @@ final class Graph
 
         $graph = new self($projectRoot);
         $graph->fingerprint = is_array($data['fingerprint'] ?? null) ? $data['fingerprint'] : [];
-        $graph->recordedAtSha = is_string($data['recorded_at_sha'] ?? null) ? $data['recorded_at_sha'] : null;
         $graph->files = is_array($data['files'] ?? null) ? array_values($data['files']) : [];
         $graph->fileIds = array_flip($graph->files);
         $graph->edges = is_array($data['edges'] ?? null) ? $data['edges'] : [];
+        $graph->baselines = is_array($data['baselines'] ?? null) ? $data['baselines'] : [];
 
         return $graph;
     }
@@ -315,9 +398,9 @@ final class Graph
         $payload = [
             'schema' => 1,
             'fingerprint' => $this->fingerprint,
-            'recorded_at_sha' => $this->recordedAtSha,
             'files' => $this->files,
             'edges' => $this->edges,
+            'baselines' => $this->baselines,
         ];
 
         $tmp = $path.'.'.bin2hex(random_bytes(4)).'.tmp';

src/Plugins/Tia/ResultCollector.php

@@ -0,0 +1,119 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Pest\Plugins\Tia;
+
+/**
+ * Collects per-test status + message during the run so the graph can persist
+ * them for faithful replay. PHPUnit's own result cache discards messages
+ * during serialisation — this collector retains them.
+ *
+ * @internal
+ */
+final class ResultCollector
+{
+    /**
+     * @var array<string, array{status: int, message: string, time: float}>
+     */
+    private array $results = [];
+
+    private ?string $currentTestId = null;
+
+    private ?float $startTime = null;
+
+    public function testPrepared(string $testId): void
+    {
+        $this->currentTestId = $testId;
+        $this->startTime = microtime(true);
+    }
+
+    public function testPassed(): void
+    {
+        if ($this->currentTestId === null) {
+            return;
+        }
+
+        $this->record(0, '');
+    }
+
+    public function testFailed(string $message): void
+    {
+        if ($this->currentTestId === null) {
+            return;
+        }
+
+        $this->record(7, $message);
+    }
+
+    public function testErrored(string $message): void
+    {
+        if ($this->currentTestId === null) {
+            return;
+        }
+
+        $this->record(8, $message);
+    }
+
+    public function testSkipped(string $message): void
+    {
+        if ($this->currentTestId === null) {
+            return;
+        }
+
+        $this->record(1, $message);
+    }
+
+    public function testIncomplete(string $message): void
+    {
+        if ($this->currentTestId === null) {
+            return;
+        }
+
+        $this->record(2, $message);
+    }
+
+    public function testRisky(string $message): void
+    {
+        if ($this->currentTestId === null) {
+            return;
+        }
+
+        $this->record(5, $message);
+    }
+
+    /**
+     * @return array<string, array{status: int, message: string, time: float}>
+     */
+    public function all(): array
+    {
+        return $this->results;
+    }
+
+    public function reset(): void
+    {
+        $this->results = [];
+        $this->currentTestId = null;
+        $this->startTime = null;
+    }
+
+    private function record(int $status, string $message): void
+    {
+        if ($this->currentTestId === null) {
+            return;
+        }
+
+        $time = $this->startTime !== null
+            ? round(microtime(true) - $this->startTime, 3)
+            : 0.0;
+
+        $this->results[$this->currentTestId] = [
+            'status' => $status,
+            'message' => $message,
+            'time' => $time,
+        ];
+
+        $this->currentTestId = null;
+        $this->startTime = null;
+    }
+}