typed_kwargs: support dict/list as "new since" types

Given a kwarg value that is itself a dict/list, we would only check if
the since_values was present within that container. If the since_values
is itself the dict or list type, then we aren't looking for recursive
structures, we just want to know when the function began to accept that
type.

This is relevant in cases where a function accepted a dict, and at one
point began accepting a list (of strings in the form 'key=value'), or
vice versa.

mesonbuild/interpreterbase/decorators.py

@@ -505,18 +505,24 @@ def typed_kwargs(name: str, *types: KwargInfo) -> T.Callable[..., T.Any]:
         @wraps(f)
         def wrapper(*wrapped_args: T.Any, **wrapped_kwargs: T.Any) -> T.Any:
 
-            def emit_feature_change(values: T.Dict[str, T.Union[str, T.Tuple[str, str]]], feature: T.Union[T.Type['FeatureDeprecated'], T.Type['FeatureNew']]) -> None:
+            def emit_feature_change(values: T.Dict[_T, T.Union[str, T.Tuple[str, str]]], feature: T.Union[T.Type['FeatureDeprecated'], T.Type['FeatureNew']]) -> None:
                 for n, version in values.items():
-                    if isinstance(value, (dict, list)):
+                    warn = False
+                    if isinstance(version, tuple):
+                        version, msg = version
+                    else:
+                        msg = None
+
+                    if n in {dict, list}:
+                        assert isinstance(n, type), 'for mypy'
+                        if isinstance(value, n):
+                            feature.single_use(f'"{name}" keyword argument "{info.name}" of type {n.__name__}', version, subproject, msg, location=node)
+                    elif isinstance(value, (dict, list)):
                         warn = n in value
                     else:
                         warn = n == value
 
                     if warn:
-                        if isinstance(version, tuple):
-                            version, msg = version
-                        else:
-                            msg = None
                         feature.single_use(f'"{name}" keyword argument "{info.name}" value "{n}"', version, subproject, msg, location=node)
 
             node, _, _kwargs, subproject = get_callee_args(wrapped_args)