attempt of interface fix

Author: soyuka

features/main/table_inheritance.feature

@@ -292,34 +292,38 @@ Feature: Table inheritance
     }
     """
 
-  # Scenario: Get the parent interface collection
-  #   When I send a "GET" request to "/resource_interfaces"
-  #   Then the response status code should be 200
-  #   And the response should be in JSON
-  #   And the header "Content-Type" should be equal to "application/ld+json; charset=utf-8"
-  #   And the JSON should be valid according to this schema:
-  #   """
-  #   {
-  #     "type": "object",
-  #     "properties": {
-  #       "hydra:member": {
-  #         "type": "array",
-  #         "items": {
-  #           "type": "object",
-  #           "properties": {
-  #             "@type": {
-  #               "type": "string",
-  #               "pattern": "^ResourceInterface$"
-  #             },
-  #             "foo": {
-  #               "type": "string",
-  #               "required": "true"
-  #             }
-  #           }
-  #         },
-  #         "minItems": 1
-  #       }
-  #     },
-  #     "required": ["hydra:member"]
-  #   }
-  #   """
+   Scenario: Get the parent interface collection
+     When I send a "GET" request to "/resource_interfaces"
+     Then the response status code should be 200
+     And the response should be in JSON
+     And the header "Content-Type" should be equal to "application/ld+json; charset=utf-8"
+     And the JSON should be valid according to this schema:
+     """
+     {
+       "type": "object",
+       "properties": {
+         "hydra:member": {
+           "type": "array",
+           "items": {
+             "type": "object",
+             "properties": {
+               "@type": {
+                 "type": "string",
+                 "pattern": "^ResourceInterface$"
+               },
+               "@id": {
+                 "type": "string",
+                 "pattern": "^_:"
+               },
+               "foo": {
+                 "type": "string",
+                 "required": "true"
+               }
+             }
+           },
+           "minItems": 1
+         }
+       },
+       "required": ["hydra:member"]
+     }
+     """

src/Api/ResourceClassResolver.php

@@ -54,6 +54,11 @@ public function getResourceClass($value, string $resourceClass = null, bool $str
             return $resourceClass;
         }
 
+        // The Resource is an interface
+        if ($value instanceof $resourceClass && $type !== $resourceClass && interface_exists($resourceClass)) {
+            throw new InvalidArgumentException(sprintf('The given object\'s resource is the interface "%s", finding a class is not possible.', $resourceClass));
+        }
+
         if (
             ($isResourceClass ?? $this->isResourceClass($type))
             || (is_subclass_of($type, $resourceClass) && $this->isResourceClass($resourceClass))