Fix #18213: Do not load fixtures with circular dependencies twice instead of throwing an exception

Author: jesse-r-s-hines

CHANGELOG.md

@@ -4,6 +4,7 @@ Yii Framework 2 Change Log
 2.0.38 under development
 ------------------------
 
+- Enh #18213: Do not load fixtures with circular dependencies twice instead of throwing an exception (JesseHines0)
 - Bug #18066: Fixed `yii\db\Query::create()` wasn't using all info from `withQuery()` (maximkou)
 - Bug #18269: Fix integer safe attribute to work properly in `yii\base\Model` (Ladone)
 - Enh #18236: Allow `yii\filters\RateLimiter` to accept a closure function for the `$user` property in order to assign values on runtime (nadar)

test/FixtureTrait.php

@@ -165,12 +165,11 @@ public function getFixture($name)
 
     /**
      * Creates the specified fixture instances.
-     * All dependent fixtures will also be created.
+     * All dependent fixtures will also be created. Duplicate fixtures and circular dependencies will only be created once.
      * @param array $fixtures the fixtures to be created. You may provide fixture names or fixture configurations.
      * If this parameter is not provided, the fixtures specified in [[globalFixtures()]] and [[fixtures()]] will be created.
      * @return Fixture[] the created fixture instances
-     * @throws InvalidConfigException if fixtures are not properly configured or if a circular dependency among
-     * the fixtures is detected.
+     * @throws InvalidConfigException if fixtures are not properly configured
      */
     protected function createFixtures(array $fixtures)
     {
@@ -210,9 +209,8 @@ protected function createFixtures(array $fixtures)
                         // need to use the configuration provided in test case
                         $stack[] = isset($config[$dep]) ? $config[$dep] : ['class' => $dep];
                     }
-                } elseif ($instances[$name] === false) {
-                    throw new InvalidConfigException("A circular dependency is detected for fixture '$class'.");
                 }
+                // if the fixture is already loaded (ie. a circular dependency or if two fixtures depend on the same fixture) just skip it.
             }
         }