minor #33343 [ErrorHandler] make DebugClassLoader turn multi-types declarations to "object" (nicolas-grekas)

This PR was merged into the 4.4 branch.

Discussion
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[ErrorHandler] make DebugClassLoader turn multi-types declarations to "object"

| Q             | A
| ------------- | ---
| Branch?       | 4.4
| Bug fix?      | no
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | -
| License       | MIT
| Doc PR        | -

When `@return Foo|Bar` is found, this makes DebugClassLoader generate an `object` return type.
When all classes in the combo type contain `Iterator`, it generates an `iterable` type instead.

Commits
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0abd2712e9 [ErrorHandler] make DebugClassLoader turn multi-types declarations to "object"

src/Symfony/Component/ErrorHandler/DebugClassLoader.php

@@ -752,6 +752,14 @@ class DebugClassLoader
             unset($typesMap['array']);
         }
 
+        $iterable = $object = true;
+        foreach ($typesMap as $n => $t) {
+            if ('null' !== $n) {
+                $iterable = $iterable && (\in_array($n, ['array', 'iterable']) || false !== strpos($n, 'Iterator'));
+                $object = $object && (\in_array($n, ['callable', 'object', '$this', 'static']) || !isset(self::SPECIAL_RETURN_TYPES[$n]));
+            }
+        }
+
         $normalizedType = key($typesMap);
         $returnType = current($typesMap);
 
@@ -762,8 +770,14 @@ class DebugClassLoader
                 $normalizedType = $t;
                 $returnType = $t;
             } elseif ($n !== $normalizedType || !preg_match('/^\\\\?[a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff]*+(?:\\\\[a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff]*+)*+$/', $n)) {
-                // ignore multi-types return declarations
-                return;
+                if ($iterable) {
+                    $normalizedType = $returnType = 'iterable';
+                } elseif ($object) {
+                    $normalizedType = $returnType = 'object';
+                } else {
+                    // ignore multi-types return declarations
+                    return;
+                }
             }
         }
 

src/Symfony/Component/HttpFoundation/Tests/Session/Storage/Handler/RedisArraySessionHandlerTest.php

@@ -13,7 +13,10 @@ namespace Symfony\Component\HttpFoundation\Tests\Session\Storage\Handler;
 
 class RedisArraySessionHandlerTest extends AbstractRedisSessionHandlerTestCase
 {
-    protected function createRedisClient(string $host): \RedisArray
+    /**
+     * @return \RedisArray|object
+     */
+    protected function createRedisClient(string $host)
     {
         return new \RedisArray([$host]);
     }

src/Symfony/Component/HttpFoundation/Tests/Session/Storage/Handler/RedisClusterSessionHandlerTest.php

@@ -24,7 +24,10 @@ class RedisClusterSessionHandlerTest extends AbstractRedisSessionHandlerTestCase
         }
     }
 
-    protected function createRedisClient(string $host): \RedisCluster
+    /**
+     * @return \RedisCluster|object
+     */
+    protected function createRedisClient(string $host)
     {
         return new \RedisCluster(null, explode(' ', getenv('REDIS_CLUSTER_HOSTS')));
     }

src/Symfony/Component/HttpFoundation/Tests/Session/Storage/Handler/RedisSessionHandlerTest.php

@@ -13,7 +13,10 @@ namespace Symfony\Component\HttpFoundation\Tests\Session\Storage\Handler;
 
 class RedisSessionHandlerTest extends AbstractRedisSessionHandlerTestCase
 {
-    protected function createRedisClient(string $host): \Redis
+    /**
+     * @return \Redis|object
+     */
+    protected function createRedisClient(string $host)
     {
         $client = new \Redis();
         $client->connect($host);