bug #34091 [Debug] work around failing chdir() on Darwin (mary2501)

This PR was merged into the 4.3 branch.

Discussion
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[Debug] work around failing chdir() on Darwin

| Q             | A
| ------------- | ---
| Branch?       |  4.3 for bug fixes <!-- see below -->
| Bug fix?      | yes
| New feature?  | no <!-- please update src/**/CHANGELOG.md files -->
| Deprecations? | no <!-- please update UPGRADE-*.md and src/**/CHANGELOG.md files -->
| Tickets       | Fix https://github.com/happybottoms/coverd/issues/15 <!-- prefix each issue number with "Fix #", if any -->
| License       | MIT
| Doc PR        | symfony/symfony-docs#... <!-- required for new features -->
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 - Always add tests and ensure they pass.
 - Never break backward compatibility (see https://symfony.com/bc).
 - Bug fixes must be submitted against the lowest maintained branch where they apply
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Commits
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f40373eb7c [Debug] work around failing chdir() on Darwin

src/Symfony/Component/Debug/DebugClassLoader.php

@@ -455,7 +455,11 @@ class DebugClassLoader
                 $real = self::$darwinCache[$kDir][0];
             } else {
                 $dir = getcwd();
-                chdir($real);
+
+                if (!@chdir($real)) {
+                    return $real.$file;
+                }
+
                 $real = getcwd().'/';
                 chdir($dir);