bug #13768 [Debug] Deprecations exception for Symfony internals (nicolas-grekas)

This PR was merged into the 2.7 branch.

Discussion
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[Debug] Deprecations exception for Symfony internals

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | #13764
| License       | MIT
| Doc PR        | -

Allowing 1st level check of the `Symfony\` namespace prevents trigerring deprecation notices for internal things, but keeps notices enabled for `Symfony\Cmf\` classes

Commits
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323e957 [Debug] Deprecations exception for Symfony internals

Author: fabpot

src/Symfony/Component/Debug/DebugClassLoader.php

@@ -180,16 +180,28 @@ public function loadClass($class)
             if (preg_match('#\n \* @deprecated (.*?)\r?\n \*(?: @|/$)#s', $refl->getDocComment(), $notice)) {
                 self::$deprecated[$name] = preg_replace('#\s*\r?\n \* +#', ' ', $notice[1]);
             } else {
-                $len = 1 + (strpos($name, '\\', 1 + strpos($name, '\\')) ?: strpos($name, '_'));
+                if (2 > $len = 1 + (strpos($name, '\\', 1 + strpos($name, '\\')) ?: strpos($name, '_'))) {
+                    $len = 0;
+                    $ns = '';
+                } else {
+                    switch ($ns = substr($name, 0, $len)) {
+                        case 'Symfony\Bridge\\':
+                        case 'Symfony\Bundle\\':
+                        case 'Symfony\Component\\':
+                            $ns = 'Symfony\\';
+                            $len = strlen($ns);
+                            break;
+                    }
+                }
                 $parent = $refl->getParentClass();
 
-                if (!$parent || $len < 2 || strncmp($name, $parent, $len)) {
-                    if ($parent && isset(self::$deprecated[$parent->name]) && ($len < 2 || strncmp($name, $parent->name, $len))) {
+                if (!$parent || strncmp($ns, $parent, $len)) {
+                    if ($parent && isset(self::$deprecated[$parent->name]) && strncmp($ns, $parent->name, $len)) {
                         trigger_error(sprintf('The %s class extends %s that is deprecated %s', $name, $parent->name, self::$deprecated[$parent->name]), E_USER_DEPRECATED);
                     }
 
                     foreach ($refl->getInterfaceNames() as $interface) {
-                        if (isset(self::$deprecated[$interface]) && ($len < 2 || strncmp($name, $interface, $len)) && !($parent && $parent->implementsInterface($interface))) {
+                        if (isset(self::$deprecated[$interface]) && strncmp($ns, $interface, $len) && !($parent && $parent->implementsInterface($interface))) {
                             trigger_error(sprintf('The %s %s %s that is deprecated %s', $name, $refl->isInterface() ? 'interface extends' : 'class implements', $interface, self::$deprecated[$interface]), E_USER_DEPRECATED);
                         }
                     }

src/Symfony/Component/Debug/Tests/DebugClassLoaderTest.php

@@ -193,7 +193,7 @@ public function testDeprecatedSuperInSameNamespace()
         $e = error_reporting(0);
         trigger_error('', E_USER_NOTICE);
 
-        class_exists(__NAMESPACE__.'\Fixtures\ExtendsDeprecatedParent', true);
+        class_exists('Symfony\Bridge\Debug\Tests\Fixtures\ExtendsDeprecatedParent', true);
 
         error_reporting($e);
         restore_error_handler();
@@ -239,8 +239,8 @@ public function findFile($class)
             return __DIR__.'/Fixtures/notPsr0Bis.php';
         } elseif (__NAMESPACE__.'\Fixtures\DeprecatedInterface' === $class) {
             return __DIR__.'/Fixtures/DeprecatedInterface.php';
-        } elseif (__NAMESPACE__.'\Fixtures\ExtendsDeprecatedParent' === $class) {
-            eval('namespace '.__NAMESPACE__.'\Fixtures; class ExtendsDeprecatedParent extends DeprecatedClass {}');
+        } elseif ('Symfony\Bridge\Debug\Tests\Fixtures\ExtendsDeprecatedParent' === $class) {
+            eval('namespace Symfony\Bridge\Debug\Tests\Fixtures; class ExtendsDeprecatedParent extends \\'.__NAMESPACE__.'\Fixtures\DeprecatedClass {}');
         } elseif ('Test\\'.__NAMESPACE__.'\DeprecatedParentClass' === $class) {
             eval('namespace Test\\'.__NAMESPACE__.'; class DeprecatedParentClass extends \\'.__NAMESPACE__.'\Fixtures\DeprecatedClass {}');
         } elseif ('Test\\'.__NAMESPACE__.'\DeprecatedInterfaceClass' === $class) {