Avoid per-argument work when coercing literal arguments

Author: patrick91

src/graphql/execution/values.py

@@ -435,6 +435,23 @@ def get_argument_values(
     return coerced_values
 
 
+def _default_value_error_handler(
+    arg_def: GraphQLArgument | GraphQLVariableSignature,
+    arg_name: str,
+    node: FieldNode | DirectiveNode | FragmentSpreadNode,
+) -> Callable[[GraphQLError, list[str | int]], None]:
+    """Build the error handler for an invalid argument default value."""
+
+    def on_arg_default_value_error(error: GraphQLError, path: list[str | int]) -> None:
+        msg = (
+            f"{print_argument_or_fragment_variable(arg_def, arg_name, node)}"
+            f" has invalid default value{print_path_list(path)}: {error.message}"
+        )
+        raise GraphQLError(msg, node)
+
+    return on_arg_default_value_error
+
+
 def coerce_argument(
     coerced_values: dict[str, Any],
     node: FieldNode | DirectiveNode | FragmentSpreadNode,
@@ -449,13 +466,6 @@ def coerce_argument(
     arg_type = arg_def.type
     out_name = getattr(arg_def, "out_name", None) or arg_name
 
-    def on_arg_default_value_error(error: GraphQLError, path: list[str | int]) -> None:
-        msg = (
-            f"{print_argument_or_fragment_variable(arg_def, arg_name, node)}"
-            f" has invalid default value{print_path_list(path)}: {error.message}"
-        )
-        raise GraphQLError(msg, node)
-
     if argument_node is None:
         if is_required_argument(arg_def):
             # Note: ProvidedRequiredArgumentsRule validation should catch this
@@ -470,7 +480,7 @@ def on_arg_default_value_error(error: GraphQLError, path: list[str | int]) -> No
             coerced_values,
             out_name,
             arg_def,
-            on_arg_default_value_error,
+            _default_value_error_handler(arg_def, arg_name, node),
             hide_suggestions,
         )
         return
@@ -495,7 +505,7 @@ def on_arg_default_value_error(error: GraphQLError, path: list[str | int]) -> No
                 coerced_values,
                 out_name,
                 arg_def,
-                on_arg_default_value_error,
+                _default_value_error_handler(arg_def, arg_name, node),
                 hide_suggestions,
             )
             return

src/graphql/utilities/coerce_input_value.py

@@ -2,7 +2,7 @@
 
 from __future__ import annotations
 
-from typing import TYPE_CHECKING, Any
+from typing import TYPE_CHECKING, Any, cast
 
 from ..language import (
     ListValueNode,
@@ -30,6 +30,7 @@
 if TYPE_CHECKING:
     from ..execution.get_variable_signature import GraphQLVariableSignature
     from ..execution.values import FragmentVariableValues, VariableValues
+    from ..language import ConstValueNode
     from ..type import GraphQLArgument, GraphQLInputField
 
 __all__ = ["coerce_default_value", "coerce_input_literal", "coerce_input_value"]
@@ -320,9 +321,14 @@ def coerce_input_literal(
     leaf_type = assert_leaf_type(type_)
     try:
         if leaf_type.coerce_input_literal is not None:
-            return leaf_type.coerce_input_literal(
+            # A bare variable was handled above, so only list and object literals
+            # can still contain variables; other literals are already constant.
+            const_node = (
                 replace_variables(value_node, variable_values, fragment_variable_values)
+                if isinstance(value_node, (ListValueNode, ObjectValueNode))
+                else cast("ConstValueNode", value_node)
             )
+            return leaf_type.coerce_input_literal(const_node)
         return leaf_type.parse_literal(
             value_node, variable_values.coerced if variable_values else None
         )