Trigger of autoloader un-tracing did not respect object (#256)

* [core] Fix untrace trigger fo symfony

* update changelog

CHANGELOG.md

@@ -6,6 +6,7 @@ All notable changes to this project will be documented in this file - [read more
 ### Fixed
 - Composer php compatibility declaration #247
 - Add missing files to PECL releases #252
+- Trigger of autoloader un-tracing did not respect object #256
 
 ## [0.10.0]
 

bridge/dd_wrap_autoloader.php

@@ -12,22 +12,36 @@
 
 $dd_autoload_called = false;
 
+$untraceTriggers = [
+    'Composer\Autoload\ClassLoader',
+];
+
 // Instead of tracing autoloaders statically, we should trace them dynamically. This can be done at the moment because
 // of https://github.com/DataDog/dd-trace-php/issues/224 and the fact that in some cases, e.g. Symfony's
 // `Symfony\Component\Config\Resource\ClassExistenceResource::throwOnRequiredClass` loaders are private.
 // As soon as this is fixed we can trace `spl_autoload_register` function and use it as a hook instead of
 // statically hooking into a limited number of class loaders.
-dd_trace('spl_autoload_register', function () use (&$dd_autoload_called) {
+dd_trace('spl_autoload_register', function () use (&$dd_autoload_called, $untraceTriggers) {
     $args = func_get_args();
     $originalAutoloaderRegistered = call_user_func_array('spl_autoload_register', $args);
 
     $loader = $args[0];
 
+    $loaderClass = null;
+    if (is_array($loader)) {
+        if (is_string($loader[0])) {
+            $loaderClass = $loader[0];
+        } elseif (is_object($loader[0])) {
+            $loaderClass = get_class($loader[0]);
+        }
+    }
+
+
     // Why unregistering spl_autoload_register?
     // In some cases (e.g. Symfony) this 'spl_autoload_register' function is called within a private scope and at the
     // moment we are working to have this use case properly handled by the extension. In the meantime we provide
     // this workaround.
-    if (is_array($loader) && $loader[0] === 'Composer\Autoload\ClassLoader' && $loader[1] === 'loadClass') {
+    if (in_array($loaderClass, $untraceTriggers)) {
         dd_untrace('spl_autoload_register');
     }