[path] Fix runtime autoload resolution for installed dev-tools

Author: coisa

src/Path/DevToolsPathResolver.php

@@ -89,6 +89,26 @@ public static function getResourcesPath(string $path = ''): string
         return self::getPackagePath(Path::join(self::RESOURCES, $path));
     }
 
+    /**
+     * Returns the active Composer autoload file for the current DevTools installation mode.
+     *
+     * When DevTools runs as a dependency, the runtime autoloader lives at the
+     * Composer vendor root. Repository checkouts instead use the package-local
+     * `vendor/autoload.php`.
+     *
+     * @param string $packagePath an optional package root path; defaults to the current package root
+     */
+    public static function getRuntimeAutoloadPath(string $packagePath = ''): string
+    {
+        $packagePath = Path::canonicalize('' === $packagePath ? self::getPackagePath() : $packagePath);
+
+        if (self::isInstalledAsDependency($packagePath)) {
+            return Path::canonicalize(Path::join($packagePath, '..', '..', 'autoload.php'));
+        }
+
+        return Path::join($packagePath, 'vendor', 'autoload.php');
+    }
+
     /**
      * Detects whether the provided path belongs to an installed vendor copy of DevTools.
      *

src/PhpUnit/Bootstrap/BootstrapShimGenerator.php

@@ -65,7 +65,7 @@ public function generate(string $projectBootstrap, string $cacheDirectory): stri
      */
     private function render(string $projectBootstrap): string
     {
-        $devToolsAutoload = DevToolsPathResolver::getPackagePath('vendor/autoload.php');
+        $devToolsAutoload = DevToolsPathResolver::getRuntimeAutoloadPath();
 
         return <<<PHP
             <?php

tests/Path/DevToolsPathResolverTest.php

@@ -37,6 +37,7 @@ public function itWillExposeCanonicalPackagePaths(): void
         self::assertSame(\dirname(__DIR__, 2), DevToolsPathResolver::getPackagePath());
         self::assertSame(\dirname(__DIR__, 2) . '/bin/dev-tools', DevToolsPathResolver::getBinaryPath());
         self::assertSame(\dirname(__DIR__, 2) . '/resources', DevToolsPathResolver::getResourcesPath());
+        self::assertSame(\dirname(__DIR__, 2) . '/vendor/autoload.php', DevToolsPathResolver::getRuntimeAutoloadPath());
         self::assertSame(
             \dirname(__DIR__, 2) . '/resources/phpdocumentor.xml',
             DevToolsPathResolver::getResourcesPath('phpdocumentor.xml')
@@ -70,4 +71,20 @@ public function itWillDetectWhetherDevToolsRunsFromVendorOrRepositoryCheckout():
             DevToolsPathResolver::isRepositoryCheckout('/workspaces/project/vendor/fast-forward/dev-tools/src')
         );
     }
+
+    /**
+     * @return void
+     */
+    #[Test]
+    public function itWillResolveRuntimeAutoloadPathsForRepositoryAndDependencyInstalls(): void
+    {
+        self::assertSame(
+            '/workspaces/dev-tools/vendor/autoload.php',
+            DevToolsPathResolver::getRuntimeAutoloadPath('/workspaces/dev-tools')
+        );
+        self::assertSame(
+            '/workspaces/project/vendor/autoload.php',
+            DevToolsPathResolver::getRuntimeAutoloadPath('/workspaces/project/vendor/fast-forward/dev-tools')
+        );
+    }
 }

tests/PhpUnit/Bootstrap/BootstrapShimGeneratorTest.php

@@ -57,7 +57,7 @@ public function generateWillWriteBootstrapShimWithProjectAndDevToolsAutoloaders(
         $projectBootstrap = '/repo/vendor/autoload.php';
         $cacheDirectory = '/repo/.dev-tools/cache/phpunit';
         $generatedBootstrapPath = '/repo/.dev-tools/cache/phpunit/bootstrap.php';
-        $devToolsAutoload = DevToolsPathResolver::getPackagePath('vendor/autoload.php');
+        $devToolsAutoload = DevToolsPathResolver::getRuntimeAutoloadPath();
         $exportedProjectBootstrap = var_export($projectBootstrap, true);
         $exportedDevToolsAutoload = var_export($devToolsAutoload, true);
         $expectedContent = <<<PHP