Add test for GraphQLResolveInfo with custom context

tests/type/test_definition.py

@@ -1,4 +1,5 @@
 import pickle
+import sys
 from enum import Enum
 from math import isnan, nan
 from typing import Dict
@@ -16,6 +17,7 @@
     InterfaceTypeExtensionNode,
     ObjectTypeDefinitionNode,
     ObjectTypeExtensionNode,
+    OperationDefinitionNode,
     ScalarTypeDefinitionNode,
     ScalarTypeExtensionNode,
     StringValueNode,
@@ -24,7 +26,7 @@
     ValueNode,
     parse_value,
 )
-from graphql.pyutils import Undefined
+from graphql.pyutils import Path, Undefined, is_awaitable
 from graphql.type import (
     GraphQLArgument,
     GraphQLEnumType,
@@ -37,7 +39,9 @@
     GraphQLList,
     GraphQLNonNull,
     GraphQLObjectType,
+    GraphQLResolveInfo,
     GraphQLScalarType,
+    GraphQLSchema,
     GraphQLString,
     GraphQLUnionType,
     introspection_types,
@@ -1301,3 +1305,40 @@ def cannot_redefine_introspection_types():
                 TypeError, match=f"Redefinition of reserved type '{name}'"
             ):
                 introspection_type.__class__(**introspection_type.to_kwargs())
+
+
+def describe_resolve_info():
+    class CustomContext:
+        """A custom context for testing"""
+
+    info_cls = GraphQLResolveInfo
+
+    info_args = {
+        "field_name": "foo",
+        "field_nodes": [],
+        "return_type": GraphQLString,
+        "parent_type": GraphQLObjectType("Foo", {}),
+        "path": Path(None, "foo", None),
+        "schema": GraphQLSchema(),
+        "fragments": {},
+        "root_value": None,
+        "operation": OperationDefinitionNode(),
+        "variable_values": {},
+        "is_awaitable": is_awaitable,
+    }
+
+    def can_create_resolve_info_with_unspecified_context_type():
+        info = info_cls(**info_args, context=CustomContext())
+        assert isinstance(info.context, CustomContext)
+        info = info_cls(**info_args, context="foo")
+        assert isinstance(info.context, str)
+
+    @pytest.mark.skipif(
+        sys.version_info < (3, 9), reason="this needs at least Python 3.9"
+    )
+    def can_create_resolve_info_with_specified_context_type():
+        info = info_cls[CustomContext](**info_args, context=CustomContext())
+        assert isinstance(info.context, CustomContext)
+        # this should not pass type checking
+        info = info_cls[CustomContext](**info_args, context="foo")  # type: ignore
+        assert isinstance(info.context, str)