CR fixes

strawberry/ext/mypy_plugin.py

@@ -1,5 +1,5 @@
 from decimal import Decimal
-from typing import Any, Callable, Dict, List, Optional, Set, Tuple
+from typing import Any, Callable, Dict, List, Optional, Set, Tuple, cast
 
 from typing_extensions import Final
 
@@ -58,6 +58,8 @@
 
 
 class MypyVersion:
+    """Stores the mypy version to be used by the plugin"""
+
     VERSION: Decimal
 
 
@@ -274,32 +276,23 @@ def is_dataclasses_field_or_strawberry_field(expr: Expression) -> bool:
     return False
 
 
-def _collect_field_args(
-    expr: Expression, ctx: ClassDefContext
-) -> Tuple[bool, Dict[str, Expression]]:
+def _collect_field_args(expr: Expression) -> Tuple[bool, Dict[str, Expression]]:
     """Returns a tuple where the first value represents whether or not
     the expression is a call to dataclass.field and the second is a
     dictionary of the keyword arguments that field() was called with.
     """
-    if (
-        isinstance(expr, CallExpr)
-        and isinstance(expr.callee, RefExpr)
-        and expr.callee.fullname == "dataclasses.field"
-    ):
+
+    if is_dataclasses_field_or_strawberry_field(expr):
+        expr = cast(CallExpr, expr)
+
         # field() only takes keyword arguments.
         args = {}
+
         for name, arg in zip(expr.arg_names, expr.args):
-            if name is None:
-                # This means that `field` is used with `**` unpacking,
-                # the best we can do for now is not to fail.
-                # TODO: we can infer what's inside `**` and try to collect it.
-                ctx.api.fail(
-                    'Unpacking **kwargs in "field()" is not supported',
-                    expr,
-                )
-                return True, {}
+            assert name is not None
             args[name] = arg
         return True, args
+
     return False, {}
 
 
@@ -500,7 +493,7 @@ def collect_attributes(self) -> Optional[List[DataclassAttribute]]:
                 is_init_var = True
                 node.type = node_type.args[0]
 
-            has_field_call, field_args = _collect_field_args(stmt.rvalue, ctx)
+            has_field_call, field_args = _collect_field_args(stmt.rvalue)
 
             is_in_init_param = field_args.get("init")
             if is_in_init_param is None: