Fix array order for array_replace_recursive merge strategy

Prior to this change, if a configuration array is defined
in extension.json, array elements cannot be overridden by
setting values in the corresponding configuration variable,
as intended by the array_replace_recursive merge strategy.
This is because the order of the arrays in the
array_replace_recursive() function call need to be
reversed.

Bug: T283464
Change-Id: I55561232a994f745c5f3cd8394674b18c0529d13

includes/registration/ExtensionRegistry.php

@@ -494,7 +494,7 @@ class ExtensionRegistry {
 					$GLOBALS[$key] = array_merge_recursive( $GLOBALS[$key], $val );
 					break;
 				case 'array_replace_recursive':
-					$GLOBALS[$key] = array_replace_recursive( $GLOBALS[$key], $val );
+					$GLOBALS[$key] = array_replace_recursive( $val, $GLOBALS[$key] );
 					break;
 				case 'array_plus_2d':
 					$GLOBALS[$key] = wfArrayPlus2d( $GLOBALS[$key], $val );

tests/phpunit/includes/registration/ExtensionRegistryTest.php

@@ -361,17 +361,17 @@ class ExtensionRegistryTest extends MediaWikiIntegrationTestCase {
 						'JsonZeroConfig' => [
 							'namespace' => 480,
 							'nsName' => 'Zero',
-							'isLocal' => true,
+							'isLocal' => false,
+							'remote' => [
+								'username' => 'foo',
+							],
 						],
 					],
 				],
 				[
 					'mwtestJsonConfigs' => [
 						'JsonZeroConfig' => [
-							'isLocal' => false,
-							'remote' => [
-								'username' => 'foo',
-							],
+							'isLocal' => true,
 						],
 						ExtensionRegistry::MERGE_STRATEGY => 'array_replace_recursive',
 					],