Explain the OPcache guard of the autoload trap e2e steps

Print a message when OPcache is not loaded, give the second step the
same comment as the first, and say why the opcache_invalidate() loop
after the trap cannot replace the one before it.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

Author: SanderMuller

.github/workflows/e2e-tests.yml

@@ -259,12 +259,14 @@ jobs:
               composer install
               # The crash needs OPcache: forked workers switch it off, the --debug main process and spawned
               # workers (pcntl_fork disabled, as on Windows) keep it on.
-              php -r 'exit(extension_loaded("Zend OPcache") ? 0 : 1);'
+              php -r 'if (!extension_loaded("Zend OPcache")) { fwrite(STDERR, "OPcache is not loaded, so this step cannot reproduce the crash.\n"); exit(1); }'
               ../../bin/phpstan analyze --debug
               php -d disable_functions=pcntl_fork ../../bin/phpstan analyze
           - script: |
               cd e2e/bootstrap-autoloader-wrong-file
-              php -r 'exit(extension_loaded("Zend OPcache") ? 0 : 1);'
+              # The crash needs OPcache: forked workers switch it off, the --debug main process and spawned
+              # workers (pcntl_fork disabled, as on Windows) keep it on.
+              php -r 'if (!extension_loaded("Zend OPcache")) { fwrite(STDERR, "OPcache is not loaded, so this step cannot reproduce the crash.\n"); exit(1); }'
               ../../bin/phpstan analyze --debug
               php -d disable_functions=pcntl_fork ../../bin/phpstan analyze
           - script: |

src/Reflection/BetterReflection/SourceLocator/AutoloadSourceLocator.php

@@ -400,7 +400,9 @@ static function () use ($className): ?array {
 	 * or a file a bootstrap autoloader included without declaring the class. With OPcache active, the
 	 * trapped include of that file runs the script OPcache compiled from the real file, not the empty
 	 * script FileReadTrapStreamWrapper serves, and dies with "Cannot redeclare". Invalidating the
-	 * entries of the included files makes that include go through the trap.
+	 * entries of the included files makes that include go through the trap. The opcache_invalidate()
+	 * loop after the trap cannot do this, because the include has already run by then. That loop removes
+	 * the empty script the trap left in OPcache.
 	 *
 	 * Forked workers switch OPcache off (see ForkedProcess), so they skip this.
 	 */