[DI] Allow defining bindings on ChildDefinition

src/Symfony/Component/DependencyInjection/ChildDefinition.php

@@ -121,14 +121,6 @@ class ChildDefinition extends Definition
     {
         throw new BadMethodCallException('A ChildDefinition cannot have instanceof conditionals set on it.');
     }
-
-    /**
-     * @internal
-     */
-    public function setBindings(array $bindings)
-    {
-        throw new BadMethodCallException('A ChildDefinition cannot have bindings set on it.');
-    }
 }
 
 class_alias(ChildDefinition::class, DefinitionDecorator::class);

src/Symfony/Component/DependencyInjection/Compiler/ResolveChildDefinitionsPass.php

@@ -103,7 +103,7 @@ class ResolveChildDefinitionsPass extends AbstractRecursivePass
         $def->setAutowired($parentDef->isAutowired());
         $def->setChanges($parentDef->getChanges());
 
-        $def->setBindings($parentDef->getBindings());
+        $def->setBindings($definition->getBindings() + $parentDef->getBindings());
 
         // overwrite with values specified in the decorator
         $changes = $definition->getChanges();

src/Symfony/Component/DependencyInjection/Tests/Compiler/ResolveChildDefinitionsPassTest.php

@@ -382,6 +382,27 @@ class ResolveChildDefinitionsPassTest extends TestCase
         $this->assertSame(array(2, 1, 'foo' => 3), $def->getArguments());
     }
 
+    public function testBindings()
+    {
+        $container = new ContainerBuilder();
+
+        $container->register('parent', 'stdClass')
+            ->setBindings(array('a' => '1', 'b' => '2'))
+        ;
+
+        $child = $container->setDefinition('child', new ChildDefinition('parent'))
+            ->setBindings(array('b' => 'B', 'c' => 'C'))
+        ;
+
+        $this->process($container);
+
+        $bindings = array();
+        foreach ($container->getDefinition('child')->getBindings() as $k => $v) {
+            $bindings[$k] = $v->getValues()[0];
+        }
+        $this->assertEquals(array('b' => 'B', 'c' => 'C', 'a' => '1'), $bindings);
+    }
+
     public function testSetAutoconfiguredOnServiceIsParent()
     {
         $container = new ContainerBuilder();