Do not let a bootstrap autoloader's exception abort the analysis (#6294)

Author: SanderMuller

.github/workflows/e2e-tests.yml

@@ -219,15 +219,24 @@ jobs:
               cd e2e/bug-14514
               composer install
               ../../bin/phpstan analyze bug-14515.php
-          # Fails since the revert of the bootstrap autoloader changes:
+          # Fails until https://github.com/phpstan/phpstan/issues/14988 is fixed again:
           # - script: |
           #     cd e2e/bug-14988
           #     composer install
           #     ../../bin/phpstan analyse
-          # - script: |
-          #     cd e2e/bug-12972b
-          #     composer install
-          #     ../../bin/phpstan analyze
+          - script: |
+              cd e2e/bug-12972b
+              composer install
+              ../../bin/phpstan analyze
+          - script: |
+              cd e2e/debug-class-loader
+              composer install
+              ../../bin/phpstan analyze
+              # With --debug, the analysis runs in the main process, and PHPStan prints the
+              # exception that DebugClassLoader threw for the unknown class.
+              OUTPUT=$(../bashunit assert exit_code "0" "../../bin/phpstan analyze --debug")
+              echo "$OUTPUT"
+              ../bashunit assert contains 'by a bootstrap autoloader for class DebugClassLoaderE2e\Widget: The autoloader expected class' "$OUTPUT"
           - script: |
               cd e2e/bug-12972c
               composer install

e2e/debug-class-loader/.gitignore

@@ -0,0 +1,2 @@
+/vendor
+/composer.lock

e2e/debug-class-loader/bootstrap.php

@@ -0,0 +1,8 @@
+<?php declare(strict_types = 1);
+
+// What a Symfony application's entry script does in dev: DebugClassLoader wraps every
+// registered autoloader and throws a RuntimeException when the file it found does not
+// declare the class it was asked for, or when the case does not match.
+require_once __DIR__ . '/vendor/autoload.php';
+
+Symfony\Component\ErrorHandler\DebugClassLoader::enable();

e2e/debug-class-loader/composer.json

@@ -0,0 +1,10 @@
+{
+	"require": {
+		"symfony/error-handler": "^7.0"
+	},
+	"autoload": {
+		"psr-4": {
+			"DebugClassLoaderE2e\\": "src/"
+		}
+	}
+}

e2e/debug-class-loader/phpstan.dist.neon

@@ -0,0 +1,12 @@
+parameters:
+	level: 6
+	bootstrapFiles:
+		- bootstrap.php
+	paths:
+		- test.php
+	ignoreErrors:
+		# The point of this project is that analysis completes and reports the unknown class
+		# instead of dying inside the autoloader.
+		-
+			message: '#^Parameter \$widget of method DebugClassLoaderE2e\\Consumer\:\:doFoo\(\) has invalid type DebugClassLoaderE2e\\Widget\.$#'
+			path: test.php

e2e/debug-class-loader/src/Widget.php

@@ -0,0 +1,10 @@
+<?php declare(strict_types = 1);
+
+namespace DebugClassLoaderE2e;
+
+// The declared name does not match the file name, so Composer's PSR-4 map sends
+// DebugClassLoaderE2e\Widget to this file and DebugClassLoader throws for it.
+class Widgets
+{
+
+}

e2e/debug-class-loader/test.php

@@ -0,0 +1,17 @@
+<?php declare(strict_types = 1);
+
+namespace DebugClassLoaderE2e;
+
+class Consumer
+{
+
+	// Nothing ever instantiates the mistyped name, so no autoloader is invoked for it at
+	// runtime. PHPStan resolves every name it sees, so it does ask - and the exception used
+	// to abort the analysis of this file with an internal error instead of reporting the
+	// unknown class. See https://github.com/phpstan/phpstan/issues/14976
+	/** @param Widget $widget */
+	public function doFoo($widget): void
+	{
+	}
+
+}

src/Command/BootstrapFilesRunner.php

@@ -4,6 +4,7 @@
 
 use PHPStan\DependencyInjection\AutowiredService;
 use PHPStan\DependencyInjection\Container;
+use PHPStan\Reflection\BetterReflection\SourceLocator\BootstrapAutoloaderExceptionReporter;
 use function spl_autoload_functions;
 
 /**
@@ -32,7 +33,10 @@ final class BootstrapFilesRunner
 
 	private bool $hasRun = false;
 
-	public function __construct(private Container $container)
+	public function __construct(
+		private Container $container,
+		private BootstrapAutoloaderExceptionReporter $bootstrapAutoloaderExceptionReporter,
+	)
 	{
 	}
 
@@ -41,6 +45,10 @@ public function __construct(private Container $container)
 	 */
 	public function run(Output $errorOutput, bool $debugEnabled): void
 	{
+		if ($debugEnabled) {
+			$this->bootstrapAutoloaderExceptionReporter->enable($errorOutput);
+		}
+
 		if ($this->hasRun) {
 			return;
 		}

src/Reflection/BetterReflection/BetterReflectionSourceLocatorFactory.php

@@ -19,6 +19,7 @@
 use PHPStan\Php\PhpVersion;
 use PHPStan\Reflection\BetterReflection\SourceLocator\AutoloadFunctionsSourceLocator;
 use PHPStan\Reflection\BetterReflection\SourceLocator\AutoloadSourceLocator;
+use PHPStan\Reflection\BetterReflection\SourceLocator\BootstrapAutoloaderExceptionReporter;
 use PHPStan\Reflection\BetterReflection\SourceLocator\CachedPhpInternalSourceLocator;
 use PHPStan\Reflection\BetterReflection\SourceLocator\ComposerJsonAndInstalledJsonSourceLocatorMaker;
 use PHPStan\Reflection\BetterReflection\SourceLocator\FileNodesFetcher;
@@ -69,6 +70,7 @@ public function __construct(
 		private ComposerJsonAndInstalledJsonSourceLocatorMaker $composerJsonAndInstalledJsonSourceLocatorMaker,
 		private OptimizedPsrAutoloaderLocatorFactory $optimizedPsrAutoloaderLocatorFactory,
 		private FileNodesFetcher $fileNodesFetcher,
+		private BootstrapAutoloaderExceptionReporter $bootstrapAutoloaderExceptionReporter,
 		#[AutowiredParameter]
 		private array $scanFiles,
 		#[AutowiredParameter]
@@ -109,6 +111,7 @@ public function create(): SourceLocator
 					$astLocator,
 					$this->reflectionSourceStubber,
 				),
+				$this->bootstrapAutoloaderExceptionReporter,
 			));
 
 			$analysedDirectories = [];

src/Reflection/BetterReflection/SourceLocator/AutoloadFunctionsSourceLocator.php

@@ -8,6 +8,7 @@
 use PHPStan\BetterReflection\Reflection\Reflection;
 use PHPStan\BetterReflection\Reflector\Reflector;
 use PHPStan\BetterReflection\SourceLocator\Type\SourceLocator;
+use Throwable;
 use function class_exists;
 use function interface_exists;
 use function PHPStan\autoloadFunctions;
@@ -19,6 +20,7 @@ final class AutoloadFunctionsSourceLocator implements SourceLocator
 	public function __construct(
 		private AutoloadSourceLocator $autoloadSourceLocator,
 		private ReflectionClassSourceLocator $reflectionClassSourceLocator,
+		private BootstrapAutoloaderExceptionReporter $exceptionReporter,
 	)
 	{
 	}
@@ -37,7 +39,22 @@ public function locateIdentifier(Reflector $reflector, Identifier $identifier):
 
 		$autoloadFunctions = autoloadFunctions();
 		foreach ($autoloadFunctions as $autoloadFunction) {
-			$autoloadFunction($className);
+			try {
+				$autoloadFunction($className);
+			} catch (Throwable $e) {
+				// This locator asks every bootstrap-registered autoloader for the class, which is not
+				// the order PHP uses: at runtime the class loader that resolves the class first is
+				// often another one, so an autoloader that throws for names outside its own scope is
+				// never invoked for them and its exception cannot happen. Letting it propagate here
+				// aborts the analysis of the file with an internal error instead, so it is swallowed
+				// and the remaining autoloaders and source locators get their turn. The class may
+				// still have been defined before the throw, so the locators below run either way.
+				// The autoloader ran for real, so its message is its real reason - with --debug,
+				// the reporter prints it.
+				// See https://github.com/phpstan/phpstan/issues/14976
+				$this->exceptionReporter->report($className, $e);
+			}
+
 			$reflection = $this->autoloadSourceLocator->locateIdentifier($reflector, $identifier);
 			if ($reflection !== null) {
 				return $reflection;