From 7ba430caf8ae41742e71092e464ab06952ea6ef4 Mon Sep 17 00:00:00 2001
From: HypeMC <hypemc@gmail.com>
Date: Tue, 13 Aug 2024 19:38:01 +0200
Subject: [PATCH] [DependencyInjection] Add `ContainerBuilder::registerChild()`
 shortcut method

---
 .../Component/DependencyInjection/CHANGELOG.md     |  1 +
 .../DependencyInjection/ContainerBuilder.php       |  9 +++++++++
 .../Tests/ContainerBuilderTest.php                 | 14 ++++++++++++--
 3 files changed, 22 insertions(+), 2 deletions(-)

diff --git a/src/Symfony/Component/DependencyInjection/CHANGELOG.md b/src/Symfony/Component/DependencyInjection/CHANGELOG.md
index f7038a59b5653..3855313ccb8e8 100644
--- a/src/Symfony/Component/DependencyInjection/CHANGELOG.md
+++ b/src/Symfony/Component/DependencyInjection/CHANGELOG.md
@@ -5,6 +5,7 @@ CHANGELOG
 ---
 
  * Deprecate `!tagged` tag, use `!tagged_iterator` instead
+ * Add a `ContainerBuilder::registerChild()` shortcut method for registering child definitions
 
 7.1
 ---
diff --git a/src/Symfony/Component/DependencyInjection/ContainerBuilder.php b/src/Symfony/Component/DependencyInjection/ContainerBuilder.php
index ee042fcc72328..b4477df4757f3 100644
--- a/src/Symfony/Component/DependencyInjection/ContainerBuilder.php
+++ b/src/Symfony/Component/DependencyInjection/ContainerBuilder.php
@@ -937,6 +937,15 @@ public function register(string $id, ?string $class = null): Definition
         return $this->setDefinition($id, new Definition($class));
     }
 
+    /**
+     * This method provides a fluid interface for easily registering a child
+     * service definition of the given parent service.
+     */
+    public function registerChild(string $id, string $parent): ChildDefinition
+    {
+        return $this->setDefinition($id, new ChildDefinition($parent));
+    }
+
     /**
      * Registers an autowired service definition.
      *
diff --git a/src/Symfony/Component/DependencyInjection/Tests/ContainerBuilderTest.php b/src/Symfony/Component/DependencyInjection/Tests/ContainerBuilderTest.php
index 612ee1112feed..5feaa3d19a83b 100644
--- a/src/Symfony/Component/DependencyInjection/Tests/ContainerBuilderTest.php
+++ b/src/Symfony/Component/DependencyInjection/Tests/ContainerBuilderTest.php
@@ -212,8 +212,18 @@ public function testRegister()
     {
         $builder = new ContainerBuilder();
         $builder->register('foo', 'Bar\FooClass');
-        $this->assertTrue($builder->hasDefinition('foo'), '->register() registers a new service definition');
-        $this->assertInstanceOf(Definition::class, $builder->getDefinition('foo'), '->register() returns the newly created Definition instance');
+        $this->assertTrue($builder->hasDefinition('foo'), '->hasDefinition() returns true if a service definition exists');
+        $this->assertInstanceOf(Definition::class, $builder->getDefinition('foo'), '->getDefinition() returns an instance of Definition');
+    }
+
+    public function testRegisterChild()
+    {
+        $builder = new ContainerBuilder();
+        $builder->register('foo', 'Bar\FooClass');
+        $builder->registerChild('bar', 'foo');
+        $this->assertTrue($builder->hasDefinition('bar'), '->hasDefinition() returns true if a service definition exists');
+        $this->assertInstanceOf(ChildDefinition::class, $definition = $builder->getDefinition('bar'), '->getDefinition() returns an instance of Definition');
+        $this->assertSame('foo', $definition->getParent(), '->getParent() returns the id of the parent service');
     }
 
     public function testAutowire()