Perf: Refactor PHPUnitVersionDetector to use runtime reflection

Author: staabm

src/Rules/PHPUnit/PHPUnitVersionDetector.php

@@ -2,45 +2,44 @@
 
 namespace PHPStan\Rules\PHPUnit;
 
-use PHPStan\Reflection\ReflectionProvider;
 use PHPUnit\Framework\TestCase;
+use ReflectionClass;
+use ReflectionException;
 use function dirname;
 use function explode;
 use function file_get_contents;
-use function is_file;
 use function json_decode;
 
 class PHPUnitVersionDetector
 {
 
-private ReflectionProvider $reflectionProvider;
-
-public function __construct(ReflectionProvider $reflectionProvider)
-{
-$this->reflectionProvider = $reflectionProvider;
-}
-
 public function createPHPUnitVersion(): PHPUnitVersion
 {
+$file = false;
 $majorVersion = null;
 $minorVersion = null;
-if ($this->reflectionProvider->hasClass(TestCase::class)) {
-$testCase = $this->reflectionProvider->getClass(TestCase::class);
-$file = $testCase->getFileName();
-if ($file !== null) {
-$phpUnitRoot = dirname($file, 3);
-$phpUnitComposer = $phpUnitRoot . '/composer.json';
-if (is_file($phpUnitComposer)) {
-$composerJson = @file_get_contents($phpUnitComposer);
-if ($composerJson !== false) {
-$json = json_decode($composerJson, true);
-$version = $json['extra']['branch-alias']['dev-main'] ?? null;
-if ($version !== null) {
-$versionParts = explode('.', $version);
-$majorVersion = (int) $versionParts[0];
-$minorVersion = (int) $versionParts[1];
-}
-}
+
+try {
+// uses runtime reflection to reduce unnecessary work while bootstrapping PHPStan.
+// static reflection would need to AST parse and build up reflection for a lot of files otherwise.
+$reflection = new ReflectionClass(TestCase::class);
+$file = $reflection->getFileName();
+} catch (ReflectionException $e) {
+// PHPUnit might not be installed
+}
+
+if ($file !== false) {
+$phpUnitRoot = dirname($file, 3);
+$phpUnitComposer = $phpUnitRoot . '/composer.json';
+
+$composerJson = @file_get_contents($phpUnitComposer);
+if ($composerJson !== false) {
+$json = json_decode($composerJson, true);
+$version = $json['extra']['branch-alias']['dev-main'] ?? null;
+if ($version !== null) {
+$versionParts = explode('.', $version);
+$majorVersion = (int) $versionParts[0];
+$minorVersion = (int) $versionParts[1];
 }
 }
 }