bug #25932 Don't stop PSR-4 service discovery if a parent class is missing (derrabus)

This PR was merged into the 3.4 branch.

Discussion
----------

Don't stop PSR-4 service discovery if a parent class is missing

| Q             | A
| ------------- | ---
| Branch?       | 3.4
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | #25929
| License       | MIT
| Doc PR        | N/A

Commits
-------

3d6c3ba836 Don't stop PSR-4 service discovery if a parent class is missing.

src/Symfony/Component/DependencyInjection/Loader/FileLoader.php

@@ -60,11 +60,16 @@ abstract class FileLoader extends BaseFileLoader
         $interfaces = array();
         $singlyImplemented = array();
 
-        foreach ($classes as $class) {
+        foreach ($classes as $class => $errorMessage) {
             if (interface_exists($class, false)) {
                 $interfaces[] = $class;
             } else {
-                $this->setDefinition($class, unserialize($serializedPrototype));
+                $this->setDefinition($class, $definition = unserialize($serializedPrototype));
+                if (null !== $errorMessage) {
+                    $definition->addError($errorMessage);
+
+                    continue;
+                }
                 foreach (class_implements($class, false) as $interface) {
                     $singlyImplemented[$interface] = isset($singlyImplemented[$interface]) ? false : $class;
                 }
@@ -139,13 +144,25 @@ abstract class FileLoader extends BaseFileLoader
             if (!preg_match('/^[a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff]*+(?:\\\\[a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff]*+)*+$/', $class)) {
                 continue;
             }
+
+            try {
+                $r = $this->container->getReflectionClass($class);
+            } catch (\ReflectionException $e) {
+                $classes[$class] = sprintf(
+                    'While discovering services from namespace "%s", an error was thrown when processing the class "%s": "%s".',
+                    $namespace,
+                    $class,
+                    $e->getMessage()
+                );
+                continue;
+            }
             // check to make sure the expected class exists
-            if (!$r = $this->container->getReflectionClass($class)) {
+            if (!$r) {
                 throw new InvalidArgumentException(sprintf('Expected to find class "%s" in file "%s" while importing services from resource "%s", but it was not found! Check the namespace prefix used with the resource.', $class, $path, $pattern));
             }
 
             if ($r->isInstantiable() || $r->isInterface()) {
-                $classes[] = $class;
+                $classes[$class] = null;
             }
         }
 

src/Symfony/Component/DependencyInjection/Tests/Fixtures/Prototype/BadClasses/MissingParent.php

@@ -0,0 +1,7 @@
+<?php
+
+namespace Symfony\Component\DependencyInjection\Tests\Fixtures\Prototype\BadClasses;
+
+class MissingParent extends MissingClass
+{
+}

src/Symfony/Component/DependencyInjection/Tests/Fixtures/config/prototype.php

@@ -9,7 +9,7 @@ return function (ContainerConfigurator $c) {
         ->tag('baz');
     $di->load(Prototype::class.'\\', '../Prototype')
         ->autoconfigure()
-        ->exclude('../Prototype/{OtherDir}')
+        ->exclude('../Prototype/{OtherDir,BadClasses}')
         ->factory('f')
         ->deprecate('%service_id%')
         ->args(array(0))

src/Symfony/Component/DependencyInjection/Tests/Fixtures/xml/services_prototype.xml

@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="utf-8"?>
 <container xmlns="http://symfony.com/schema/dic/services" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://symfony.com/schema/dic/services http://symfony.com/schema/dic/services/services-1.0.xsd">
   <services>
-      <prototype namespace="Symfony\Component\DependencyInjection\Tests\Fixtures\Prototype\" resource="../Prototype/*" exclude="../Prototype/{OtherDir}" />
+      <prototype namespace="Symfony\Component\DependencyInjection\Tests\Fixtures\Prototype\" resource="../Prototype/*" exclude="../Prototype/{OtherDir,BadClasses}" />
   </services>
 </container>

src/Symfony/Component/DependencyInjection/Tests/Fixtures/yaml/services_prototype.yml

@@ -1,4 +1,4 @@
 services:
     Symfony\Component\DependencyInjection\Tests\Fixtures\Prototype\:
         resource: ../Prototype
-        exclude: '../Prototype/{OtherDir}'
+        exclude: '../Prototype/{OtherDir,BadClasses}'

src/Symfony/Component/DependencyInjection/Tests/Loader/FileLoaderTest.php

@@ -25,6 +25,7 @@ use Symfony\Component\DependencyInjection\Loader\PhpFileLoader;
 use Symfony\Component\DependencyInjection\Loader\XmlFileLoader;
 use Symfony\Component\DependencyInjection\Loader\YamlFileLoader;
 use Symfony\Component\DependencyInjection\Reference;
+use Symfony\Component\DependencyInjection\Tests\Fixtures\Prototype\BadClasses\MissingParent;
 use Symfony\Component\DependencyInjection\Tests\Fixtures\Prototype\OtherDir\AnotherSub\DeeperBaz;
 use Symfony\Component\DependencyInjection\Tests\Fixtures\Prototype\OtherDir\Baz;
 use Symfony\Component\DependencyInjection\Tests\Fixtures\Prototype\Foo;
@@ -163,6 +164,26 @@ class FileLoaderTest extends TestCase
         $this->assertFalse($alias->isPrivate());
     }
 
+    public function testMissingParentClass()
+    {
+        $container = new ContainerBuilder();
+        $container->setParameter('bad_classes_dir', 'BadClasses');
+        $loader = new TestFileLoader($container, new FileLocator(self::$fixturesPath.'/Fixtures'));
+
+        $loader->registerClasses(
+            (new Definition())->setPublic(false),
+            'Symfony\Component\DependencyInjection\Tests\Fixtures\Prototype\BadClasses\\',
+            'Prototype/%bad_classes_dir%/*'
+        );
+
+        $this->assertTrue($container->has(MissingParent::class));
+
+        $this->assertSame(
+            array('While discovering services from namespace "Symfony\Component\DependencyInjection\Tests\Fixtures\Prototype\BadClasses\", an error was thrown when processing the class "Symfony\Component\DependencyInjection\Tests\Fixtures\Prototype\BadClasses\MissingParent": "Class Symfony\Component\DependencyInjection\Tests\Fixtures\Prototype\BadClasses\MissingClass not found".'),
+            $container->getDefinition(MissingParent::class)->getErrors()
+        );
+    }
+
     /**
      * @expectedException \Symfony\Component\DependencyInjection\Exception\InvalidArgumentException
      * @expectedExceptionMessageRegExp /Expected to find class "Symfony\\Component\\DependencyInjection\\Tests\\Fixtures\\Prototype\\Bar" in file ".+" while importing services from resource "Prototype\/Sub\/\*", but it was not found\! Check the namespace prefix used with the resource/