Fixes #16838: yii\mutex\Mutex::acquire() no longer returns true if lock is already acquired by the same component in the same process

framework/CHANGELOG.md

@@ -78,6 +78,7 @@ Yii Framework 2 Change Log
 - Bug #15204: `yii\helpers\BaseInflector::slug()` is not removing substrings matching provided replacement from given string anymore (bizley)
 - Bug #16101: Fixed Error Handler to clear registered meta tags, link tags, css/js scripts and files in error view (bizley)
 - Bug #16836: Fix `yii\mutex\MysqlMutex` to handle locks with names longer than 64 characters (rob006)
+- Bug #16838: `yii\mutex\Mutex::acquire()` no longer returns `true` if lock is already acquired by the same component in the same process (rob006)
 - Enh #16839: Increase frequency of lock tries for `yii\mutex\FileMutex::acquireLock()` when $timeout is provided (rob006)
 - Enh #16839: Add support for `$timeout` in  `yii\mutex\PgsqlMutex::acquire()` (rob006)
 - Bug #16828: `yii\console\controllers\MessageController::translator` recognized object' methods and functions calls as identical sets of tokens (erickskrauch)

framework/UPGRADE.md

@@ -62,6 +62,17 @@ Upgrade from Yii 2.0.15
   ```json
   "cebe/markdown": "~1.1.0",
   ```
+  
+* `yii\mutex\Mutex::acquire()` no longer returns `true` if lock is already acquired by the same component in the same process.
+  Make sure that you're not trying to acquire the same lock multiple times in a way that may create infinite loops, for example:
+    
+  ```php
+  if (Yii::$app->mutex->acquire('test')) {
+       while (!Yii::$app->mutex->acquire('test')) {
+           // `Yii::$app->mutex->acquire('test')` will always return `false` here, since lock is already acquired
+      }
+  }
+  ```
 
 
 Upgrade from Yii 2.0.14

framework/mutex/Mutex.php

@@ -69,7 +69,7 @@ abstract class Mutex extends Component
      */
     public function acquire($name, $timeout = 0)
     {
-        if ($this->acquireLock($name, $timeout)) {
+        if (!in_array($name, $this->_locks, true) && $this->acquireLock($name, $timeout)) {
             $this->_locks[] = $name;
 
             return true;