Instead of using is_nullish, use a more Pythonic "is None" check.

Author: faassen

graphql/core/execution/executor.py

@@ -8,7 +8,6 @@
 from ..language.source import Source
 from ..type import GraphQLEnumType, GraphQLInterfaceType, GraphQLList, GraphQLNonNull, GraphQLObjectType, \
     GraphQLScalarType, GraphQLUnionType
-from ..utils.is_nullish import is_nullish
 from ..validation import validate
 from .base import ExecutionContext, ExecutionResult, ResolveInfo, Undefined, collect_fields, default_resolve_fn, \
     get_argument_values, get_field_def, get_operation_root_type
@@ -224,7 +223,7 @@ def complete_value(self, ctx, return_type, field_asts, info, result):
             return completed
 
         # If result is null-like, return null.
-        if is_nullish(result):
+        if result is None:
             return None
 
         # If field type is List, complete each item in the list with the inner type
@@ -248,7 +247,7 @@ def complete_value(self, ctx, return_type, field_asts, info, result):
         if isinstance(return_type, (GraphQLScalarType, GraphQLEnumType)):
             serialized_result = return_type.serialize(result)
 
-            if is_nullish(serialized_result):
+            if serialized_result is None:
                 return None
 
             return serialized_result

graphql/core/execution/values.py

@@ -11,7 +11,6 @@
     GraphQLScalarType,
     is_input_type
 )
-from ..utils.is_nullish import is_nullish
 from ..utils.is_valid_value import is_valid_value
 from ..utils.type_from_ast import type_from_ast
 from ..utils.value_from_ast import value_from_ast
@@ -56,10 +55,10 @@ def get_argument_values(arg_defs, arg_asts, variables):
             variables
         )
 
-        if is_nullish(value):
+        if value is None:
             value = arg_def.default_value
 
-        if not is_nullish(value):
+        if value is not None:
             result[name] = value
 
     return result
@@ -81,14 +80,14 @@ def get_variable_value(schema, definition_ast, input):
         )
 
     if is_valid_value(type, input):
-        if is_nullish(input):
+        if input is None:
             default_value = definition_ast.default_value
             if default_value:
                 return value_from_ast(default_value, type)
 
         return coerce_value(type, input)
 
-    if is_nullish(input):
+    if input is None:
         raise GraphQLError(
             'Variable "${}" of required type "{}" was not provided.'.format(
                 variable.name.value,
@@ -115,7 +114,7 @@ def coerce_value(type, value):
         # We only call this function after calling isValidValue.
         return coerce_value(type.of_type, value)
 
-    if is_nullish(value):
+    if value is None:
         return None
 
     if isinstance(type, GraphQLList):
@@ -130,19 +129,15 @@ def coerce_value(type, value):
         obj = {}
         for field_name, field in fields.items():
             field_value = coerce_value(field.type, value[field_name])
-            if is_nullish(field_value):
+            if field_value is None:
                 field_value = field.default_value
 
-            if not is_nullish(field_value):
+            if field_value is not None:
                 obj[field_name] = field_value
 
         return obj
 
     assert isinstance(type, (GraphQLScalarType, GraphQLEnumType)), \
         'Must be input type'
 
-    parsed = type.parse_value(value)
-    if not is_nullish(parsed):
-        return parsed
-
-    return None
+    return type.parse_value(value)

graphql/core/utils/ast_from_value.py

@@ -11,14 +11,13 @@
     GraphQLNonNull,
 )
 from ..type.scalars import GraphQLFloat
-from .is_nullish import is_nullish
 
 
 def ast_from_value(value, type=None):
     if isinstance(type, GraphQLNonNull):
         return ast_from_value(value, type.of_type)
 
-    if is_nullish(value):
+    if value is None:
         return None
 
     if isinstance(value, list):

graphql/core/utils/is_nullish.py

@@ -6,7 +6,6 @@
     GraphQLNonNull,
     GraphQLScalarType,
 )
-from .is_nullish import is_nullish
 
 
 def is_valid_literal_value(type, value_ast):
@@ -49,4 +48,4 @@ def is_valid_literal_value(type, value_ast):
 
     assert isinstance(type, (GraphQLScalarType, GraphQLEnumType)), 'Must be input type'
 
-    return not is_nullish(type.parse_literal(value_ast))
+    return type.parse_literal(value_ast) is not None

graphql/core/utils/is_valid_literal_value.py

@@ -11,18 +11,17 @@
     GraphQLNonNull,
     GraphQLScalarType,
 )
-from .is_nullish import is_nullish
 
 
 def is_valid_value(type, value):
     """Given a type and any value, return True if that value is valid."""
     if isinstance(type, GraphQLNonNull):
-        if is_nullish(value):
+        if value is None:
             return False
 
         return is_valid_value(type.of_type, value)
 
-    if is_nullish(value):
+    if value is None:
         return True
 
     if isinstance(type, GraphQLList):
@@ -54,4 +53,4 @@ def is_valid_value(type, value):
 
     # Scalar/Enum input checks to ensure the type can parse the value to
     # a non-null value.
-    return not is_nullish(type.parse_value(value))
+    return type.parse_value(value) is not None

graphql/core/utils/is_valid_value.py

@@ -8,7 +8,6 @@
     GraphQLUnionType
 )
 from .ast_from_value import ast_from_value
-from .is_nullish import is_nullish
 
 
 def print_schema(schema):
@@ -118,7 +117,7 @@ def _print_args(field):
 
 
 def _print_input_value(arg):
-    if not is_nullish(arg.default_value):
+    if arg.default_value is not None:
         default_value = ' = ' + print_ast(ast_from_value(arg.default_value, arg.type))
     else:
         default_value = ''

graphql/core/utils/schema_printer.py

@@ -1,6 +1,5 @@
 from ..language import ast
 from ..type import (GraphQLEnumType, GraphQLInputObjectType, GraphQLList, GraphQLNonNull, GraphQLScalarType)
-from .is_nullish import is_nullish
 
 
 def value_from_ast(value_ast, type, variables=None):
@@ -63,8 +62,4 @@ def value_from_ast(value_ast, type, variables=None):
     assert isinstance(type, (GraphQLScalarType, GraphQLEnumType)), \
         'Must be input type'
 
-    parsed = type.parse_literal(value_ast)
-    if not is_nullish(parsed):
-        return parsed
-
-    return None
+    return type.parse_literal(value_ast)

graphql/core/utils/value_from_ast.py

@@ -1,8 +1,6 @@
 from collections import OrderedDict
 from graphql.core.type.definition import GraphQLField, GraphQLArgument, GraphQLInputObjectField, GraphQLEnumValue
 from graphql.core.utils.schema_printer import print_schema, print_introspection_schema
-from graphql.core.utils.is_nullish import is_nullish
-from graphql.core.language.printer import print_ast
 from graphql.core.type import (
     GraphQLSchema,
     GraphQLInputObjectType,
@@ -526,4 +524,4 @@ def test_prints_introspection_schema():
   LIST
   NON_NULL
 }
-'''
+'''