Handle $id property for draft6 in validates()

docs/spelling-wordlist.txt

@@ -15,6 +15,7 @@ indices
 ipv
 iterable
 jsonschema
+pre
 programmatically
 recurses
 regex

jsonschema/tests/test_validators.py

@@ -76,6 +76,28 @@ def test_if_a_version_is_not_provided_it_is_not_registered(self):
             validators.create(meta_schema={u"id": "id"})
         self.assertFalse(validates.called)
 
+    def test_if_validates_registers_meta_schema_id(self):
+        meta_schema_key = "meta schema id"
+        my_meta_schema = {u"id": meta_schema_key}
+
+        validators.create(
+            meta_schema=my_meta_schema,
+            version="my version",
+        )
+
+        self.assertIn(meta_schema_key, validators.meta_schemas)
+
+    def test_if_validates_registers_meta_schema_draft6_id(self):
+        meta_schema_key = "meta schema $id"
+        my_meta_schema = {u"$id": meta_schema_key}
+
+        validators.create(
+            meta_schema=my_meta_schema,
+            version="my version",
+        )
+
+        self.assertIn(meta_schema_key, validators.meta_schemas)
+
     def test_extend(self):
         original_validators = dict(self.Validator.VALIDATORS)
         new = mock.Mock()
@@ -1025,6 +1047,17 @@ def test_custom_validator(self):
             Validator,
         )
 
+    def test_custom_validator_draft6(self):
+        Validator = validators.create(
+            meta_schema={"$id": "meta schema $id"},
+            version="13",
+        )
+        schema = {"$schema": "meta schema $id"}
+        self.assertIs(
+            validators.validator_for(schema),
+            Validator,
+        )
+
     def test_validator_for_jsonschema_default(self):
         self.assertIs(validators.validator_for({}), validators._LATEST_VERSION)
 

jsonschema/validators.py

@@ -36,7 +36,9 @@ def validates(version):
     Register the decorated validator for a ``version`` of the specification.
 
     Registered validators and their meta schemas will be considered when
-    parsing ``$schema`` properties' URIs.
+    parsing ``$schema`` properties' URIs. Meta schemas can use either
+    ``id`` or ``$id`` depending on whether they follow pre-draft6 or draft6
+    and later, respectively.
 
     Arguments:
 
@@ -54,6 +56,8 @@ def _validates(cls):
         validators[version] = cls
         if u"id" in cls.META_SCHEMA:
             meta_schemas[cls.META_SCHEMA[u"id"]] = cls
+        elif u"$id" in cls.META_SCHEMA:
+            meta_schemas[cls.META_SCHEMA[u"$id"]] = cls
         return cls
     return _validates