bug #41777 [DependencyInjection] accept service locator definitions with no class (nicolas-grekas)

This PR was merged into the 5.3 branch.

Discussion
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[DependencyInjection] accept service locator definitions with no class

| Q             | A
| ------------- | ---
| Branch?       | 5.3
| Bug fix?      | yes
| New feature?  | no
| Deprecations? | no
| Tickets       | Fix #40861, fix #41612
| License       | MIT
| Doc PR        | -

Commits
-------

6bc8ec6c9a [DependencyInjection] accept service locator definitions with no class

Author: nicolas-grekas

Compiler/CheckDefinitionValidityPass.php

@@ -44,7 +44,7 @@ public function process(ContainerBuilder $container)
             }
 
             // non-synthetic, non-abstract service has class
-            if (!$definition->isAbstract() && !$definition->isSynthetic() && !$definition->getClass() && (!$definition->getFactory() || !preg_match(FileLoader::ANONYMOUS_ID_REGEXP, $id))) {
+            if (!$definition->isAbstract() && !$definition->isSynthetic() && !$definition->getClass() && !$definition->hasTag('container.service_locator') && (!$definition->getFactory() || !preg_match(FileLoader::ANONYMOUS_ID_REGEXP, $id))) {
                 if ($definition->getFactory()) {
                     throw new RuntimeException(sprintf('Please add the class to service "%s" even if it is constructed by a factory since we might need to add method calls based on compile-time checks.', $id));
                 }

Tests/Compiler/CheckDefinitionValidityPassTest.php

@@ -37,6 +37,16 @@ public function testProcessDetectsNonSyntheticNonAbstractDefinitionWithoutClass(
         $this->process($container);
     }
 
+    public function testProcessAcceptsServiceLocatorWithoutClass()
+    {
+        $container = new ContainerBuilder();
+        $container->register('a')->addTag('container.service_locator');
+
+        $this->process($container);
+
+        $this->addToAssertionCount(1);
+    }
+
     public function testProcessDetectsFactoryWithoutClass()
     {
         $container = new ContainerBuilder();