Make use of structural pattern matching

Author: Cito

src/graphql/type/introspection.py

@@ -13,19 +13,19 @@
     GraphQLEnumValue,
     GraphQLField,
     GraphQLFieldMap,
+    GraphQLInputObjectType,
+    GraphQLInterfaceType,
     GraphQLList,
     GraphQLNamedType,
     GraphQLNonNull,
     GraphQLObjectType,
+    GraphQLScalarType,
+    GraphQLUnionType,
     is_abstract_type,
     is_enum_type,
     is_input_object_type,
     is_interface_type,
-    is_list_type,
-    is_non_null_type,
     is_object_type,
-    is_scalar_type,
-    is_union_type,
 )
 from .scalars import GraphQLBoolean, GraphQLString
 
@@ -312,26 +312,27 @@ def __new__(cls):
 
     @staticmethod
     def kind(type_, _info):
-        if is_scalar_type(type_):
-            return TypeKind.SCALAR
-        if is_object_type(type_):
-            return TypeKind.OBJECT
-        if is_interface_type(type_):
-            return TypeKind.INTERFACE
-        if is_union_type(type_):
-            return TypeKind.UNION
-        if is_enum_type(type_):
-            return TypeKind.ENUM
-        if is_input_object_type(type_):
-            return TypeKind.INPUT_OBJECT
-        if is_list_type(type_):
-            return TypeKind.LIST
-        if is_non_null_type(type_):
-            return TypeKind.NON_NULL
-
-        # Not reachable. All possible types have been considered.
-        msg = f"Unexpected type: {inspect(type_)}."  # pragma: no cover
-        raise TypeError(msg)  # pragma: no cover
+        match type_:
+            case GraphQLScalarType():
+                return TypeKind.SCALAR
+            case GraphQLObjectType():
+                return TypeKind.OBJECT
+            case GraphQLInterfaceType():
+                return TypeKind.INTERFACE
+            case GraphQLUnionType():
+                return TypeKind.UNION
+            case GraphQLEnumType():
+                return TypeKind.ENUM
+            case GraphQLInputObjectType():
+                return TypeKind.INPUT_OBJECT
+            case GraphQLList():
+                return TypeKind.LIST
+            case GraphQLNonNull():
+                return TypeKind.NON_NULL
+            case _:  # pragma: no cover
+                # Not reachable. All possible types have been considered.
+                msg = f"Unexpected type: {inspect(type_)}."
+                raise TypeError(msg)
 
     @staticmethod
     def name(type_, _info):

src/graphql/utilities/extend_schema.py

@@ -75,17 +75,11 @@
     GraphQLUnionTypeKwargs,
     assert_schema,
     introspection_types,
-    is_enum_type,
-    is_input_object_type,
-    is_interface_type,
     is_introspection_type,
     is_list_type,
     is_non_null_type,
-    is_object_type,
-    is_scalar_type,
     is_specified_directive,
     is_specified_scalar_type,
-    is_union_type,
     specified_scalar_types,
 )
 from .value_from_ast import value_from_ast
@@ -312,22 +306,23 @@ def extend_named_type(self, type_: GraphQLNamedType) -> GraphQLNamedType:
         if is_introspection_type(type_) or is_specified_scalar_type(type_):
             # Builtin types are not extended.
             return type_
-        if is_scalar_type(type_):
-            return self.extend_scalar_type(type_)
-        if is_object_type(type_):
-            return self.extend_object_type(type_)
-        if is_interface_type(type_):
-            return self.extend_interface_type(type_)
-        if is_union_type(type_):
-            return self.extend_union_type(type_)
-        if is_enum_type(type_):
-            return self.extend_enum_type(type_)
-        if is_input_object_type(type_):
-            return self.extend_input_object_type(type_)
-
-        # Not reachable. All possible types have been considered.
-        msg = f"Unexpected type: {inspect(type_)}."  # pragma: no cover
-        raise TypeError(msg)  # pragma: no cover
+        match type_:
+            case GraphQLScalarType():
+                return self.extend_scalar_type(type_)
+            case GraphQLObjectType():
+                return self.extend_object_type(type_)
+            case GraphQLInterfaceType():
+                return self.extend_interface_type(type_)
+            case GraphQLUnionType():
+                return self.extend_union_type(type_)
+            case GraphQLEnumType():
+                return self.extend_enum_type(type_)
+            case GraphQLInputObjectType():
+                return self.extend_input_object_type(type_)
+            case _:  # pragma: no cover
+                # Not reachable. All possible types have been considered.
+                msg = f"Unexpected type: {inspect(type_)}."
+                raise TypeError(msg)
 
     def extend_input_object_type_fields(
         self, kwargs: GraphQLInputObjectTypeKwargs, extensions: tuple[Any, ...]

src/graphql/utilities/find_breaking_changes.py

@@ -15,6 +15,7 @@
     GraphQLInterfaceType,
     GraphQLNamedType,
     GraphQLObjectType,
+    GraphQLScalarType,
     GraphQLSchema,
     GraphQLType,
     GraphQLUnionType,
@@ -27,7 +28,6 @@
     is_object_type,
     is_required_argument,
     is_required_input_field,
-    is_scalar_type,
     is_specified_scalar_type,
     is_union_type,
 )
@@ -543,22 +543,23 @@ def is_change_safe_for_input_object_field_or_field_arg(
 
 
 def type_kind_name(type_: GraphQLNamedType) -> str:
-    if is_scalar_type(type_):
-        return "a Scalar type"
-    if is_object_type(type_):
-        return "an Object type"
-    if is_interface_type(type_):
-        return "an Interface type"
-    if is_union_type(type_):
-        return "a Union type"
-    if is_enum_type(type_):
-        return "an Enum type"
-    if is_input_object_type(type_):
-        return "an Input type"
-
-    # Not reachable. All possible output types have been considered.
-    msg = f"Unexpected type {inspect(type_)}"  # pragma: no cover
-    raise TypeError(msg)  # pragma: no cover
+    match type_:
+        case GraphQLScalarType():
+            return "a Scalar type"
+        case GraphQLObjectType():
+            return "an Object type"
+        case GraphQLInterfaceType():
+            return "an Interface type"
+        case GraphQLUnionType():
+            return "a Union type"
+        case GraphQLEnumType():
+            return "an Enum type"
+        case GraphQLInputObjectType():
+            return "an Input type"
+        case _:  # pragma: no cover
+            # Not reachable. All possible named types have been considered.
+            msg = f"Unexpected type {inspect(type_)}"
+            raise TypeError(msg)
 
 
 def stringify_value(value: Any, type_: GraphQLInputType) -> str:

src/graphql/utilities/print_schema.py

@@ -21,14 +21,8 @@
     GraphQLScalarType,
     GraphQLSchema,
     GraphQLUnionType,
-    is_enum_type,
-    is_input_object_type,
-    is_interface_type,
     is_introspection_type,
-    is_object_type,
-    is_scalar_type,
     is_specified_directive,
-    is_union_type,
 )
 from .ast_from_value import ast_from_value
 
@@ -138,22 +132,23 @@ def has_default_root_operation_types(schema: GraphQLSchema) -> bool:
 
 def print_type(type_: GraphQLNamedType) -> str:
     """Print a named GraphQL type."""
-    if is_scalar_type(type_):
-        return print_scalar(type_)
-    if is_object_type(type_):
-        return print_object(type_)
-    if is_interface_type(type_):
-        return print_interface(type_)
-    if is_union_type(type_):
-        return print_union(type_)
-    if is_enum_type(type_):
-        return print_enum(type_)
-    if is_input_object_type(type_):
-        return print_input_object(type_)
-
-    # Not reachable. All possible types have been considered.
-    msg = f"Unexpected type: {inspect(type_)}."  # pragma: no cover
-    raise TypeError(msg)  # pragma: no cover
+    match type_:
+        case GraphQLScalarType():
+            return print_scalar(type_)
+        case GraphQLObjectType():
+            return print_object(type_)
+        case GraphQLInterfaceType():
+            return print_interface(type_)
+        case GraphQLUnionType():
+            return print_union(type_)
+        case GraphQLEnumType():
+            return print_enum(type_)
+        case GraphQLInputObjectType():
+            return print_input_object(type_)
+        case _:  # pragma: no cover
+            # Not reachable. All possible types have been considered.
+            msg = f"Unexpected type: {inspect(type_)}."
+            raise TypeError(msg)
 
 
 def print_scalar(type_: GraphQLScalarType) -> str: