BUGFIX: neos#3303 Flush reflection cache for removed php classes

There are a few layers to this bugfix.

1. Previously we ignored deleted files (see `file_exists`) and did not flush the `Flow_Reflection_Status` cache accordingly as we are not able to read the namespace from a deleted php file.
Now we do a best effort reverse lookup by going through all psr-4 autoload configurations and calculate a namespace under which composer would have found this file.

2. We introduce a state `removedReflectionDataClasses` like `updatedReflectionData` which will be used to check if we have to update the `ReflectionData` cache.

Neos.Flow/Classes/Cache/CacheManager.php

@@ -20,6 +20,8 @@
 use Neos\Cache\Frontend\VariableFrontend;
 use Neos\Flow\Configuration\ConfigurationManager;
 use Neos\Flow\Log\Utility\LogEnvironment;
+use Neos\Flow\Monitor\ChangeDetectionStrategy\ChangeDetectionStrategyInterface;
+use Neos\Flow\Package\PackageManager;
 use Neos\Flow\Utility\Environment;
 use Neos\Utility\Files;
 use Neos\Flow\Utility\PhpAnalyzer;
@@ -47,6 +49,11 @@ class CacheManager
      */
     protected $configurationManager;
 
+    /**
+     * @var PackageManager
+     */
+    protected $packageManager;
+
     /**
      * @var LoggerInterface
      */
@@ -118,6 +125,11 @@ public function injectConfigurationManager(ConfigurationManager $configurationMa
         $this->configurationManager = $configurationManager;
     }
 
+    public function injectPackageManager(PackageManager $packageManager): void
+    {
+        $this->packageManager = $packageManager;
+    }
+
     /**
      * @param Environment $environment
      * @return void
@@ -352,15 +364,35 @@ protected function flushClassCachesByChangedFiles(array $changedFiles): void
         $modifiedAspectClassNamesWithUnderscores = [];
         $modifiedClassNamesWithUnderscores = [];
         foreach ($changedFiles as $pathAndFilename => $status) {
-            if (!file_exists($pathAndFilename)) {
-                continue;
+            $classNameWithUnderscores = null;
+            if ($status !== ChangeDetectionStrategyInterface::STATUS_DELETED) {
+                $fileContents = file_get_contents($pathAndFilename);
+                $className = (new PhpAnalyzer($fileContents))->extractFullyQualifiedClassName();
+                if ($className === null) {
+                    continue;
+                }
+                $classNameWithUnderscores = str_replace('\\', '_', $className);
+            } else {
+                // file was deleted
+                foreach ($this->packageManager->getFlowPackages() as $flowPackage) {
+                    if (!str_starts_with($pathAndFilename, $flowPackage->getPackagePath())) {
+                        continue;
+                    }
+                    foreach ($flowPackage->getFlattenedAutoloadConfiguration() as $autoloadConfiguration) {
+                        if (!str_starts_with($pathAndFilename, $autoloadConfiguration['classPath'])) {
+                            continue;
+                        }
+                        $relativePath = substr($pathAndFilename, strlen($autoloadConfiguration['classPath']), -strlen('.php'));
+                        $classNameWithUnderscores = str_replace('\\', '_', rtrim($autoloadConfiguration['namespace'], '\\')) . '_' . str_replace('/', '_', ltrim($relativePath, '/'));
+                        break 2;
+                    }
+                }
             }
-            $fileContents = file_get_contents($pathAndFilename);
-            $className = (new PhpAnalyzer($fileContents))->extractFullyQualifiedClassName();
-            if ($className === null) {
+
+            if ($classNameWithUnderscores === null) {
                 continue;
             }
-            $classNameWithUnderscores = str_replace('\\', '_', $className);
+
             $modifiedClassNamesWithUnderscores[$classNameWithUnderscores] = true;
 
             // If an aspect was modified, the whole code cache needs to be flushed, so keep track of them:

Neos.Flow/Classes/Core/Booting/Scripts.php

@@ -377,6 +377,7 @@ public static function initializeCacheManagement(Bootstrap $bootstrap)
         $cacheManager = new CacheManager();
         $cacheManager->setCacheConfigurations($configurationManager->getConfiguration(ConfigurationManager::CONFIGURATION_TYPE_CACHES));
         $cacheManager->injectConfigurationManager($configurationManager);
+        $cacheManager->injectPackageManager($bootstrap->getEarlyInstance(PackageManager::class));
         $cacheManager->injectLogger($bootstrap->getEarlyInstance(PsrLoggerFactoryInterface::class)->get('systemLogger'));
         $cacheManager->injectEnvironment($environment);
         $cacheManager->injectCacheFactory($cacheFactory);

Neos.Flow/Classes/Reflection/ReflectionService.php

@@ -174,6 +174,11 @@ class ReflectionService
      */
     protected array $updatedReflectionData = [];
 
+    /**
+     * Array with removed reflection information (e.g. in Development context after classes were deleted)
+     */
+    protected array $removedReflectionDataClasses = [];
+
     protected bool $initialized = false;
 
     /**
@@ -1833,6 +1838,8 @@ protected function forgetClass($className): void
 
         unset($this->classReflectionData[$className]);
         unset($this->classesCurrentlyBeingForgotten[$className]);
+
+        $this->removedReflectionDataClasses[$className] = true;
     }
 
     /**
@@ -2024,7 +2031,7 @@ public function saveToCache(): void
             $this->reflectionDataRuntimeCache->set('__availableClassNames', $this->availableClassNames);
         }
 
-        if ($this->updatedReflectionData !== []) {
+        if ($this->updatedReflectionData !== [] || $this->removedReflectionDataClasses !== []) {
             $this->updateReflectionData();
         }
 
@@ -2092,7 +2099,7 @@ protected function saveProductionData(): void
      */
     protected function updateReflectionData(): void
     {
-        $this->log(sprintf('Found %s classes whose reflection data was not cached previously.', count($this->updatedReflectionData)), LogLevel::DEBUG);
+        $this->log(sprintf('Found %s classes whose reflection data was not cached previously and %s classes which were deleted.', count($this->updatedReflectionData), count($this->removedReflectionDataClasses)), LogLevel::DEBUG);
 
         foreach (array_keys($this->updatedReflectionData) as $className) {
             $this->statusCache->set($this->produceCacheIdentifierFromClassName($className), '');