chore: add some explanations and explicit check callouts to mypy ignores

Signed-off-by: Ihar Hrachyshka <ihar.hrachyshka@gmail.com>

llama_stack/strong_typing/auxiliary.py

@@ -77,7 +77,9 @@ def typeannotation(
     """
 
     def wrap(cls: Type[T]) -> Type[T]:
-        cls.__repr__ = _compact_dataclass_repr  # type: ignore
+        # mypy fails to equate bound-y functions (first argument interpreted as
+        # the bound object) with class methods, hence the `ignore` directive.
+        cls.__repr__ = _compact_dataclass_repr  # type: ignore[method-assign]
         if not dataclasses.is_dataclass(cls):
             cls = dataclasses.dataclass(  # type: ignore[call-overload]
                 cls,

llama_stack/strong_typing/deserializer.py

@@ -627,7 +627,8 @@ class NamedTupleDeserializer(ClassDeserializer[NamedTuple]):
         super().assign(property_parsers)
 
     def create(self, **field_values: Any) -> NamedTuple:
-        return self.class_type(**field_values)  # type: ignore
+        # mypy fails to deduce that this class returns NamedTuples only, hence the `ignore` directive
+        return self.class_type(**field_values)  # type: ignore[no-any-return]
 
 
 class DataclassDeserializer(ClassDeserializer[T]):

llama_stack/strong_typing/inspection.py

@@ -260,7 +260,8 @@ def extend_enum(
         values: Dict[str, Any] = {}
         values.update((e.name, e.value) for e in source)
         values.update((e.name, e.value) for e in extend)
-        enum_class: Type[enum.Enum] = enum.Enum(extend.__name__, values)  # type: ignore
+        # mypy fails to determine that __name__ is always a string; hence the `ignore` directive.
+        enum_class: Type[enum.Enum] = enum.Enum(extend.__name__, values)  # type: ignore[misc]
 
         # assign the newly created type to the same module where the extending class is defined
         enum_class.__module__ = extend.__module__
@@ -327,9 +328,7 @@ def _unwrap_optional_type(typ: Type[Optional[T]]) -> Type[T]:
         raise TypeError("optional type must have un-subscripted type of Union")
 
     # will automatically unwrap Union[T] into T
-    return Union[
+    return Union[tuple(filter(lambda item: item is not type(None), typing.get_args(typ)))]  # type: ignore[return-value]
-        tuple(filter(lambda item: item is not type(None), typing.get_args(typ)))  # type: ignore
-    ]
 
 
 def is_type_union(typ: object) -> bool:
@@ -431,7 +430,7 @@ def _unwrap_generic_list(typ: Type[List[T]]) -> Type[T]:
     "Extracts the item type of a list type (e.g. returns `T` for `List[T]`)."
 
     (list_type,) = typing.get_args(typ)  # unpack single tuple element
-    return list_type  # type: ignore
+    return list_type  # type: ignore[no-any-return]
 
 
 def is_generic_set(typ: object) -> TypeGuard[Type[set]]:
@@ -456,7 +455,7 @@ def _unwrap_generic_set(typ: Type[Set[T]]) -> Type[T]:
     "Extracts the item type of a set type (e.g. returns `T` for `Set[T]`)."
 
     (set_type,) = typing.get_args(typ)  # unpack single tuple element
-    return set_type  # type: ignore
+    return set_type  # type: ignore[no-any-return]
 
 
 def is_generic_dict(typ: object) -> TypeGuard[Type[dict]]:
@@ -513,7 +512,7 @@ def unwrap_annotated_type(typ: T) -> T:
 
     if is_type_annotated(typ):
         # type is Annotated[T, ...]
-        return typing.get_args(typ)[0]  # type: ignore
+        return typing.get_args(typ)[0]  # type: ignore[no-any-return]
     else:
         # type is a regular type
         return typ
@@ -538,7 +537,7 @@ def rewrap_annotated_type(transform: Callable[[Type[S]], Type[T]], typ: Type[S])
     transformed_type = transform(inner_type)
 
     if metadata is not None:
-        return Annotated[(transformed_type, *metadata)]  # type: ignore
+        return Annotated[(transformed_type, *metadata)]  # type: ignore[return-value]
     else:
         return transformed_type
 

llama_stack/strong_typing/schema.py

@@ -463,10 +463,14 @@ class JsonSchemaGenerator:
             ret: Schema = {"oneOf": [self.type_to_schema(union_type) for union_type in typing.get_args(typ)]}
             if discriminator:
                 # for each union type, we need to read the value of the discriminator
-                mapping: JsonType = {}
+                mapping: dict[str, JsonType] = {}
                 for union_type in typing.get_args(typ):
                     props = self.type_to_schema(union_type, force_expand=True)["properties"]
-                    mapping[props[discriminator]["default"]] = self.type_to_schema(union_type)["$ref"]  # type: ignore
+                    # mypy is confused here because JsonType allows multiple types, some of them
+                    # not indexable (bool?) or not indexable by string (list?). The correctness of
+                    # types depends on correct model definitions. Hence multiple ignore statements below.
+                    discriminator_value = props[discriminator]["default"]  # type: ignore[index,call-overload]
+                    mapping[discriminator_value] = self.type_to_schema(union_type)["$ref"]  # type: ignore[index]
 
                 ret["discriminator"] = {
                     "propertyName": discriminator,