show @oneOf in introspection query

gql/cli.py

@@ -140,7 +140,9 @@ def get_parser(with_examples: bool = False) -> ArgumentParser:
              - input_value_deprecation:false  to omit deprecated input fields
              - specified_by_url:true
              - schema_description:true
-             - directive_is_repeatable:true"""
+             - directive_is_repeatable:true
+             - input_object_one_of:true
+             """
         ),
         dest="schema_download",
     )
@@ -430,6 +432,7 @@ def get_introspection_args(args: Namespace) -> Dict:
         "directive_is_repeatable",
         "schema_description",
         "input_value_deprecation",
+        "input_object_one_of",
     ]
 
     if args.schema_download is not None:

gql/utilities/get_introspection_query_ast.py

@@ -11,6 +11,8 @@ def get_introspection_query_ast(
     directive_is_repeatable: bool = False,
     schema_description: bool = False,
     input_value_deprecation: bool = True,
+    input_object_one_of: bool = False,
+    *,
     type_recursion_level: int = 7,
 ) -> DocumentNode:
     """Get a query for introspection as a document using the DSL module.
@@ -68,6 +70,13 @@ def get_introspection_query_ast(
     )
     if descriptions:
         fragment_FullType.select(ds.__Type.description)
+    if input_object_one_of:
+        try:
+            fragment_FullType.select(ds.__Type.isOneOf)
+        except AttributeError:  # pragma: no cover
+            raise NotImplementedError(
+                "isOneOf is only supported from graphql-core version 3.3.0a7"
+            )
     if specified_by_url:
         fragment_FullType.select(ds.__Type.specifiedByURL)
 

setup.py

@@ -16,6 +16,7 @@
 
 tests_requires = [
     "parse==1.20.2",
+    "packaging>=21.0",
     "pytest==8.3.4",
     "pytest-asyncio==0.25.3",
     "pytest-console-scripts==1.4.1",

tests/starwars/test_dsl.py

@@ -15,11 +15,15 @@
     NonNullTypeNode,
     NullValueNode,
     Undefined,
+)
+from graphql import __version__ as graphql_version
+from graphql import (
     build_ast_schema,
     parse,
     print_ast,
 )
 from graphql.utilities import get_introspection_query
+from packaging import version
 
 from gql import Client, gql
 from gql.dsl import (
@@ -1084,6 +1088,50 @@ def test_get_introspection_query_ast(option):
         )
 
 
+@pytest.mark.skipif(
+    version.parse(graphql_version) < version.parse("3.3.0a7"),
+    reason="Requires graphql-core >= 3.3.0a7",
+)
+@pytest.mark.parametrize("option", [True, False])
+def test_get_introspection_query_ast_is_one_of(option):
+
+    introspection_query = print_ast(
+        gql(
+            get_introspection_query(
+                input_value_deprecation=option,
+            )
+        ).document
+    )
+
+    # Because the option does not exist yet in graphql-core,
+    # we add it manually here for now
+    if option:
+        introspection_query = introspection_query.replace(
+            "fields",
+            "isOneOf\n  fields",
+        )
+
+    dsl_introspection_query = get_introspection_query_ast(
+        input_value_deprecation=option,
+        input_object_one_of=option,
+        type_recursion_level=9,
+    )
+
+    assert introspection_query == print_ast(dsl_introspection_query)
+
+
+@pytest.mark.skipif(
+    version.parse(graphql_version) >= version.parse("3.3.0a7"),
+    reason="Test only for older graphql-core versions < 3.3.0a7",
+)
+def test_get_introspection_query_ast_is_one_of_not_implemented_yet():
+
+    with pytest.raises(NotImplementedError):
+        get_introspection_query_ast(
+            input_object_one_of=True,
+        )
+
+
 def test_typename_aliased(ds):
     query = """
 hero {

tests/test_cli.py

@@ -407,6 +407,7 @@ def test_cli_parse_schema_download(parser):
             "specified_by_url:True",
             "schema_description:true",
             "directive_is_repeatable:true",
+            "input_object_one_of:true",
             "--print-schema",
         ]
     )
@@ -419,6 +420,7 @@ def test_cli_parse_schema_download(parser):
         "specified_by_url": True,
         "schema_description": True,
         "directive_is_repeatable": True,
+        "input_object_one_of": True,
     }
 
     assert introspection_args == expected_args