wip

src/Plugins/Tia/CoverageCollector.php

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+<?php
+
+declare(strict_types=1);
+
+namespace Pest\Plugins\Tia;
+
+use PHPUnit\Runner\CodeCoverage as PhpUnitCodeCoverage;
+use ReflectionClass;
+use Throwable;
+
+/**
+ * Extracts per-test file coverage from PHPUnit's shared `CodeCoverage`
+ * instance. Used when TIA piggybacks on `--coverage` instead of starting
+ * its own driver session — both share the same PCOV / Xdebug state, so
+ * running two recorders in parallel would corrupt each other's data.
+ *
+ * PHPUnit tags every coverage sample with the current test's id
+ * (`$test->valueObjectForEvents()->id()`, e.g. `Foo\BarTest::baz`). The
+ * per-file / per-line coverage map therefore already carries everything
+ * we need to rebuild TIA edges at the end of the run.
+ *
+ * @internal
+ */
+final class CoverageCollector
+{
+    /**
+     * Cached `className → test file` lookups. Class reflection is cheap
+     * individually but the record run can visit tens of thousands of
+     * samples, so the cache matters.
+     *
+     * @var array<string, string|null>
+     */
+    private array $classFileCache = [];
+
+    /**
+     * Rebuilds the same `absolute test file → list<absolute source file>`
+     * shape that `Recorder::perTestFiles()` exposes, so callers can treat
+     * the two collectors interchangeably when feeding the graph.
+     *
+     * @return array<string, array<int, string>>
+     */
+    public function perTestFiles(): array
+    {
+        if (! PhpUnitCodeCoverage::instance()->isActive()) {
+            return [];
+        }
+
+        try {
+            $lineCoverage = PhpUnitCodeCoverage::instance()
+                ->codeCoverage()
+                ->getData()
+                ->lineCoverage();
+        } catch (Throwable) {
+            return [];
+        }
+
+        /** @var array<string, array<string, true>> $edges */
+        $edges = [];
+
+        foreach ($lineCoverage as $sourceFile => $lines) {
+            // Collect the set of tests that hit any line in this file once,
+            // then emit one edge per (testFile, sourceFile) pair. Walking
+            // the lines per test would re-resolve the test file repeatedly.
+            $testIds = [];
+
+            foreach ($lines as $hits) {
+                if ($hits === null) {
+                    continue;
+                }
+
+                foreach ($hits as $id) {
+                    $testIds[$id] = true;
+                }
+            }
+
+            foreach (array_keys($testIds) as $testId) {
+                $testFile = $this->testIdToFile($testId);
+
+                if ($testFile === null) {
+                    continue;
+                }
+
+                $edges[$testFile][$sourceFile] = true;
+            }
+        }
+
+        $out = [];
+
+        foreach ($edges as $testFile => $sources) {
+            $out[$testFile] = array_keys($sources);
+        }
+
+        return $out;
+    }
+
+    public function reset(): void
+    {
+        $this->classFileCache = [];
+    }
+
+    private function testIdToFile(string $testId): ?string
+    {
+        // PHPUnit's test id is `ClassName::methodName` with an optional
+        // `#dataSetName` suffix for data-provider runs. Strip the dataset
+        // part — we only need the class.
+        $hash = strpos($testId, '#');
+        $identifier = $hash === false ? $testId : substr($testId, 0, $hash);
+
+        if (! str_contains($identifier, '::')) {
+            return null;
+        }
+
+        [$className] = explode('::', $identifier, 2);
+
+        if (array_key_exists($className, $this->classFileCache)) {
+            return $this->classFileCache[$className];
+        }
+
+        $file = $this->resolveClassFile($className);
+        $this->classFileCache[$className] = $file;
+
+        return $file;
+    }
+
+    private function resolveClassFile(string $className): ?string
+    {
+        if (! class_exists($className, false)) {
+            return null;
+        }
+
+        $reflection = new ReflectionClass($className);
+
+        // Pest's eval'd test classes expose the original `.php` path on a
+        // static `$__filename`. The eval'd class itself has no file of its
+        // own, so prefer this property when present.
+        if ($reflection->hasProperty('__filename')) {
+            $property = $reflection->getProperty('__filename');
+
+            if ($property->isStatic()) {
+                $value = $property->getValue();
+
+                if (is_string($value)) {
+                    return $value;
+                }
+            }
+        }
+
+        $file = $reflection->getFileName();
+
+        return is_string($file) ? $file : null;
+    }
+}