Allow to disable lock without defining a resource

Author: MatTheCat

DependencyInjection/Configuration.php

@@ -1117,12 +1117,15 @@ private function addLockSection(ArrayNodeDefinition $rootNode)
                         })
                     ->end()
                     ->addDefaultsIfNotSet()
+                    ->validate()
+                        ->ifTrue(static function (array $config) { return $config['enabled'] && !$config['resources']; })
+                        ->thenInvalid('At least one resource must be defined.')
+                    ->end()
                     ->fixXmlConfig('resource')
                     ->children()
                         ->arrayNode('resources')
                             ->normalizeKeys(false)
                             ->useAttributeAsKey('name')
-                            ->requiresAtLeastOneElement()
                             ->defaultValue(['default' => [class_exists(SemaphoreStore::class) && SemaphoreStore::isSupported() ? 'semaphore' : 'flock']])
                             ->beforeNormalization()
                                 ->ifString()->then(function ($v) { return ['default' => $v]; })

Tests/DependencyInjection/ConfigurationTest.php

@@ -378,6 +378,31 @@ public function testItErrorsWhenDefaultBusDoesNotExist()
         ]);
     }
 
+    public function testLockCanBeDisabled()
+    {
+        $processor = new Processor();
+        $configuration = new Configuration(true);
+
+        $config = $processor->processConfiguration($configuration, [
+            ['lock' => ['enabled' => false]],
+        ]);
+
+        $this->assertFalse($config['lock']['enabled']);
+    }
+
+    public function testEnabledLockNeedsResources()
+    {
+        $processor = new Processor();
+        $configuration = new Configuration(true);
+
+        $this->expectException(InvalidConfigurationException::class);
+        $this->expectExceptionMessage('Invalid configuration for path "framework.lock": At least one resource must be defined.');
+
+        $processor->processConfiguration($configuration, [
+            ['lock' => ['enabled' => true]],
+        ]);
+    }
+
     protected static function getBundleDefaultConfig()
     {
         return [