[container] support subscribed services in child classes (#102)

Author: seferov

README.md

@@ -12,7 +12,7 @@ vendor/bin/psalm-plugin enable psalm/plugin-symfony
 ### Features
 
 - Detect `ContainerInterface::get()` result type. Works better if you [configure](#configuration) compiled container XML file.
-- Support [Service Subscribers](https://github.com/psalm/psalm-plugin-symfony/issues/20).
+- Support [Service Subscribers](https://github.com/psalm/psalm-plugin-symfony/issues/20). Works only if you [configure](#configuration) compiled container XML file.
 - Detect return type of console arguments (`InputInterface::getArgument()`) and options (`InputInterface::getOption()`). Enforces
 to use InputArgument and InputOption constants as a part of best practise.
 - Detects correct Doctrine repository class if entities are configured with annotations.

src/Handler/ContainerHandler.php

@@ -4,6 +4,7 @@
 
 use PhpParser\Node\Expr;
 use PhpParser\Node\Expr\ClassConstFetch;
+use PhpParser\Node\Name;
 use PhpParser\Node\Scalar\String_;
 use PhpParser\Node\Stmt\Class_;
 use PhpParser\Node\Stmt\ClassLike;
@@ -18,6 +19,7 @@
 use Psalm\Plugin\Hook\AfterMethodCallAnalysisInterface;
 use Psalm\StatementsSource;
 use Psalm\Storage\ClassLikeStorage;
+use Psalm\Storage\FileStorage;
 use Psalm\SymfonyPsalmPlugin\Issue\NamingConventionViolation;
 use Psalm\SymfonyPsalmPlugin\Issue\PrivateService;
 use Psalm\SymfonyPsalmPlugin\Issue\ServiceNotFound;
@@ -146,30 +148,24 @@ public static function afterClassLikeVisit(
         }
 
         // see https://symfony.com/doc/current/service_container/service_subscribers_locators.html
-        if (self::$containerMeta && $stmt instanceof Class_ && isset($storage->class_implements['symfony\contracts\service\servicesubscriberinterface'])) {
+        if (self::$containerMeta && $stmt instanceof Class_ && in_array('getsubscribedservices', array_keys($storage->methods))) {
             foreach ($stmt->stmts as $classStmt) {
                 if ($classStmt instanceof ClassMethod && 'getSubscribedServices' === $classStmt->name->name && $classStmt->stmts) {
                     foreach ($classStmt->stmts as $methodStmt) {
-                        if ($methodStmt instanceof Return_ && ($return = $methodStmt->expr) && $return instanceof Expr\Array_) {
-                            foreach ($return->items as $arrayItem) {
-                                if ($arrayItem instanceof Expr\ArrayItem) {
-                                    $value = $arrayItem->value;
-                                    if (!$value instanceof Expr\ClassConstFetch) {
-                                        continue;
-                                    }
-
-                                    /** @var string $className */
-                                    $className = $value->class->getAttribute('resolvedName');
-
-                                    $key = $arrayItem->key;
-                                    $serviceId = $key instanceof String_ ? $key->value : $className;
-
-                                    $service = new Service($serviceId, $className);
-                                    $service->setIsPublic(true);
-                                    self::$containerMeta->add($service);
+                        if (!$methodStmt instanceof Return_) {
+                            continue;
+                        }
 
-                                    $codebase->queueClassLikeForScanning($className);
-                                    $fileStorage->referenced_classlikes[strtolower($className)] = $className;
+                        $return = $methodStmt->expr;
+                        if ($return instanceof Expr\Array_) {
+                            self::addSubscribedServicesArray($return, $codebase, $fileStorage);
+                        } elseif ($return instanceof Expr\FuncCall) {
+                            $funcName = $return->name;
+                            if ($funcName instanceof Name && in_array('array_merge', $funcName->parts)) {
+                                foreach ($return->args as $arg) {
+                                    if ($arg->value instanceof Expr\Array_) {
+                                        self::addSubscribedServicesArray($arg->value, $codebase, $fileStorage);
+                                    }
                                 }
                             }
                         }
@@ -179,6 +175,35 @@ public static function afterClassLikeVisit(
         }
     }
 
+    private static function addSubscribedServicesArray(Expr\Array_ $array, Codebase $codebase, FileStorage $fileStorage): void
+    {
+        if (!self::$containerMeta) {
+            return;
+        }
+
+        foreach ($array->items as $arrayItem) {
+            if ($arrayItem instanceof Expr\ArrayItem) {
+                $value = $arrayItem->value;
+                if (!$value instanceof Expr\ClassConstFetch) {
+                    continue;
+                }
+
+                /** @var string $className */
+                $className = $value->class->getAttribute('resolvedName');
+
+                $key = $arrayItem->key;
+                $serviceId = $key instanceof String_ ? $key->value : $className;
+
+                $service = new Service($serviceId, $className);
+                $service->setIsPublic(true);
+                self::$containerMeta->add($service);
+
+                $codebase->queueClassLikeForScanning($className);
+                $fileStorage->referenced_classlikes[strtolower($className)] = $className;
+            }
+        }
+    }
+
     private static function isContainerMethod(string $declaringMethodId, string $methodName): bool
     {
         return in_array(

tests/acceptance/acceptance/ServiceSubscriber.feature

@@ -62,3 +62,34 @@ Feature: Service Subscriber
       | Trace | $entityManager: Doctrine\ORM\EntityManagerInterface                  |
       | Trace | $validator: Symfony\Component\Validator\Validator\ValidatorInterface |
     And I see no other errors
+
+
+  Scenario: Asserting psalm recognizes return type of services defined in getSubscribedServices using array_merge
+    Given I have the following code
+      """
+      <?php
+
+      use Doctrine\ORM\EntityManagerInterface;
+      use Symfony\Bundle\FrameworkBundle\Controller\AbstractController;
+
+      class SomeController extends AbstractController
+      {
+        public function __invoke()
+        {
+          /** @psalm-trace $entityManager */
+          $entityManager = $this->container->get('custom_service');
+        }
+
+        public static function getSubscribedServices(): array
+        {
+          return array_merge([
+            'custom_service' => EntityManagerInterface::class,
+          ], parent::getSubscribedServices());
+        }
+      }
+      """
+    When I run Psalm
+    Then I see these errors
+      | Type  | Message                                             |
+      | Trace | $entityManager: Doctrine\ORM\EntityManagerInterface |
+    And I see no other errors