test_single_field_subscriptions: extract test schema from harness

Replicates graphql/graphql-js@d82c8e2

Author: Cito

tests/validation/harness.py

@@ -9,7 +9,6 @@
 
 __all__ = [
     "test_schema",
-    "empty_schema",
     "assert_validation_errors",
     "assert_sdl_validation_errors",
 ]
@@ -134,23 +133,8 @@
       complicatedArgs: ComplicatedArgs
     }
 
-    type Message {
-      body: String
-      sender: String
-    }
-
-    type SubscriptionRoot {
-      importantEmails: [String]
-      notImportantEmails: [String]
-      moreImportantEmails: [String]
-      spamEmails: [String]
-      deletedEmails: [String]
-      newMessage: Message
-    }
-
     schema {
       query: QueryRoot
-      subscription: SubscriptionRoot
     }
 
     directive @onQuery on QUERY
@@ -164,18 +148,6 @@
     """
 )
 
-empty_schema = build_schema(
-    """
-    type QueryRoot {
-      empty: Boolean
-    }
-
-    schema {
-      query: QueryRoot
-    }
-    """
-)
-
 
 def assert_validation_errors(
     rule: Type[ValidationRule],

tests/validation/test_single_field_subscriptions.py

@@ -1,10 +1,40 @@
 from functools import partial
 
+from graphql.utilities import build_schema
 from graphql.validation import SingleFieldSubscriptionsRule
 
-from .harness import assert_validation_errors, empty_schema
+from .harness import assert_validation_errors
 
-assert_errors = partial(assert_validation_errors, SingleFieldSubscriptionsRule)
+schema = build_schema(
+    """
+    type Message {
+      body: String
+      sender: String
+    }
+
+    type SubscriptionRoot {
+      importantEmails: [String]
+      notImportantEmails: [String]
+      moreImportantEmails: [String]
+      spamEmails: [String]
+      deletedEmails: [String]
+      newMessage: Message
+    }
+
+    type QueryRoot {
+      dummy: String
+    }
+
+    schema {
+      query: QueryRoot
+      subscription: SubscriptionRoot
+    }
+    """
+)
+
+assert_errors = partial(
+    assert_validation_errors, SingleFieldSubscriptionsRule, schema=schema
+)
 
 assert_valid = partial(assert_errors, errors=[])
 
@@ -262,6 +292,13 @@ def fails_with_introspection_field_in_anonymous_subscription():
         )
 
     def skips_if_not_subscription_type():
+        empty_schema = build_schema(
+            """
+            type Query {
+              dummy: String
+            }
+            """
+        )
         assert_errors(
             """
             subscription {