Fix mypy issues and bring extra type hints

Author: KingDarBoja

gql/client.py

@@ -211,7 +211,9 @@ def _execute(self, document: DocumentNode, *args, **kwargs) -> ExecutionResult:
 
         return self.transport.execute(document, *args, **kwargs)
 
-    def execute(self, document: DocumentNode, *args, **kwargs) -> Dict:
+    def execute(
+        self, document: DocumentNode, *args, **kwargs
+    ) -> Optional[Dict[str, Any]]:
 
         # Validate and execute on the transport
         result = self._execute(document, *args, **kwargs)
@@ -225,7 +227,9 @@ def execute(self, document: DocumentNode, *args, **kwargs) -> Dict:
         ), "Transport returned an ExecutionResult without data or errors"
 
         if self.client.type_adapter:
-            result.data = self.client.type_adapter.convert_scalars(result.data)
+            result = result._replace(
+                data=self.client.type_adapter.convert_scalars(result.data)
+            )
 
         return result.data
 
@@ -289,7 +293,7 @@ async def _subscribe(
 
     async def subscribe(
         self, document: DocumentNode, *args, **kwargs
-    ) -> AsyncGenerator[Dict, None]:
+    ) -> AsyncGenerator[Optional[Dict[str, Any]], None]:
 
         # Validate and subscribe on the transport
         async for result in self._subscribe(document, *args, **kwargs):
@@ -300,7 +304,9 @@ async def subscribe(
 
             elif result.data is not None:
                 if self.client.type_adapter:
-                    result.data = self.client.type_adapter.convert_scalars(result.data)
+                    result = result._replace(
+                        data=self.client.type_adapter.convert_scalars(result.data)
+                    )
                 yield result.data
 
     async def _execute(
@@ -316,7 +322,9 @@ async def _execute(
             self.client.execute_timeout,
         )
 
-    async def execute(self, document: DocumentNode, *args, **kwargs) -> Dict:
+    async def execute(
+        self, document: DocumentNode, *args, **kwargs
+    ) -> Optional[Dict[str, Any]]:
 
         # Validate and execute on the transport
         result = await self._execute(document, *args, **kwargs)
@@ -330,7 +338,9 @@ async def execute(self, document: DocumentNode, *args, **kwargs) -> Dict:
         ), "Transport returned an ExecutionResult without data or errors"
 
         if self.client.type_adapter:
-            result.data = self.client.type_adapter.convert_scalars(result.data)
+            result = result._replace(
+                data=self.client.type_adapter.convert_scalars(result.data)
+            )
 
         return result.data
 

gql/type_adapter.py

@@ -1,4 +1,4 @@
-from typing import Any, Dict, List, Optional, Union
+from typing import Any, Dict, List, Optional, Union, cast
 
 from graphql import GraphQLSchema
 from graphql.type.definition import GraphQLField, GraphQLObjectType, GraphQLScalarType
@@ -88,7 +88,7 @@ def traverse_schema(
         except (KeyError, AttributeError):
             return None
 
-    def _get_decoded_scalar_type(self, keys: List[str], value: Any):
+    def _get_decoded_scalar_type(self, keys: List[str], value: str) -> str:
         """Get the decoded value of the type identified by `keys`.
 
         If the type is not a custom scalar, then return the original value.
@@ -100,7 +100,7 @@ def _get_decoded_scalar_type(self, keys: List[str], value: Any):
             return self.custom_types[scalar_type].parse_value(value)
         return value
 
-    def convert_scalars(self, response: Dict[str, Any]):
+    def convert_scalars(self, response: Dict[str, Any]) -> Dict[str, Any]:
         """Recursively traverse the GQL response
 
         Recursively traverses the GQL response and calls _get_decoded_scalar_type()
@@ -114,7 +114,9 @@ def convert_scalars(self, response: Dict[str, Any]):
         Builds a new tree with the substituted values so old `response` is not
         modified."""
 
-        def iterate(node: Union[List, Dict, str], keys: List[str] = None):
+        def iterate(
+            node: Union[List, Dict, str], keys: List[str] = None
+        ) -> Union[Dict[str, Any], List, str]:
             if keys is None:
                 keys = []
             if isinstance(node, dict):
@@ -126,4 +128,4 @@ def iterate(node: Union[List, Dict, str], keys: List[str] = None):
             else:
                 return self._get_decoded_scalar_type(keys, node)
 
-        return iterate(response)
+        return cast(Dict, iterate(response))