Further improve typing of builtins brain (#2225)

Resolves 12 mypy errors

Co-authored-by: Daniël van Noord <[email protected]>

astroid/arguments.py

@@ -91,7 +91,7 @@ def _unpack_keywords(
         keywords: list[tuple[str | None, nodes.NodeNG]],
         context: InferenceContext | None = None,
     ):
-        values = {}
+        values: dict[str | None, InferenceResult] = {}
         context = context or InferenceContext()
         context.extra_context = self.argument_context_map
         for name, value in keywords:

astroid/brain/brain_builtin_inference.py

@@ -7,9 +7,9 @@
 from __future__ import annotations
 
 import itertools
-from collections.abc import Callable, Iterator
+from collections.abc import Callable, Iterable
 from functools import partial
-from typing import Any, Type, Union, cast
+from typing import TYPE_CHECKING, Any, Iterator, NoReturn, Type, Union, cast
 
 from astroid import arguments, helpers, inference_tip, nodes, objects, util
 from astroid.builder import AstroidBuilder
@@ -29,6 +29,9 @@
     SuccessfulInferenceResult,
 )
 
+if TYPE_CHECKING:
+    from astroid.bases import Instance
+
 ContainerObjects = Union[
     objects.FrozenSet,
     objects.DictItems,
@@ -43,6 +46,13 @@
     Type[frozenset],
 ]
 
+CopyResult = Union[
+    nodes.Dict,
+    nodes.List,
+    nodes.Set,
+    objects.FrozenSet,
+]
+
 OBJECT_DUNDER_NEW = "object.__new__"
 
 STR_CLASS = """
@@ -127,6 +137,10 @@ def ljust(self, width, fillchar=None):
 """
 
 
+def _use_default() -> NoReturn:  # pragma: no cover
+    raise UseInferenceDefault()
+
+
 def _extend_string_class(class_node, code, rvalue):
     """Function to extend builtin str/unicode class."""
     code = code.format(rvalue=rvalue)
@@ -193,7 +207,9 @@ def register_builtin_transform(transform, builtin_name) -> None:
     an optional context.
     """
 
-    def _transform_wrapper(node, context: InferenceContext | None = None):
+    def _transform_wrapper(
+        node: nodes.Call, context: InferenceContext | None = None, **kwargs: Any
+    ) -> Iterator:
         result = transform(node, context=context)
         if result:
             if not result.parent:
@@ -257,10 +273,12 @@ def _container_generic_transform(
     iterables: tuple[type[nodes.BaseContainer] | type[ContainerObjects], ...],
     build_elts: BuiltContainers,
 ) -> nodes.BaseContainer | None:
+    elts: Iterable | str | bytes
+
     if isinstance(arg, klass):
         return arg
     if isinstance(arg, iterables):
-        arg = cast(ContainerObjects, arg)
+        arg = cast(Union[nodes.BaseContainer, ContainerObjects], arg)
         if all(isinstance(elt, nodes.Const) for elt in arg.elts):
             elts = [cast(nodes.Const, elt).value for elt in arg.elts]
         else:
@@ -277,9 +295,10 @@ def _container_generic_transform(
                     elts.append(evaluated_object)
     elif isinstance(arg, nodes.Dict):
         # Dicts need to have consts as strings already.
-        if not all(isinstance(elt[0], nodes.Const) for elt in arg.items):
-            raise UseInferenceDefault()
-        elts = [item[0].value for item in arg.items]
+        elts = [
+            item[0].value if isinstance(item[0], nodes.Const) else _use_default()
+            for item in arg.items
+        ]
     elif isinstance(arg, nodes.Const) and isinstance(arg.value, (str, bytes)):
         elts = arg.value
     else:
@@ -399,6 +418,7 @@ def infer_dict(node: nodes.Call, context: InferenceContext | None = None) -> nod
     args = call.positional_arguments
     kwargs = list(call.keyword_arguments.items())
 
+    items: list[tuple[InferenceResult, InferenceResult]]
     if not args and not kwargs:
         # dict()
         return nodes.Dict(
@@ -695,7 +715,9 @@ def infer_slice(node, context: InferenceContext | None = None):
     return slice_node
 
 
-def _infer_object__new__decorator(node, context: InferenceContext | None = None):
+def _infer_object__new__decorator(
+    node: nodes.ClassDef, context: InferenceContext | None = None, **kwargs: Any
+) -> Iterator[Instance]:
     # Instantiate class immediately
     # since that's what @object.__new__ does
     return iter((node.instantiate_class(),))
@@ -944,10 +966,10 @@ def _build_dict_with_elements(elements):
     if isinstance(inferred_values, nodes.Const) and isinstance(
         inferred_values.value, (str, bytes)
     ):
-        elements = [
+        elements_with_value = [
             (nodes.Const(element), default) for element in inferred_values.value
         ]
-        return _build_dict_with_elements(elements)
+        return _build_dict_with_elements(elements_with_value)
     if isinstance(inferred_values, nodes.Dict):
         keys = inferred_values.itered()
         for key in keys:
@@ -964,7 +986,7 @@ def _build_dict_with_elements(elements):
 
 def _infer_copy_method(
     node: nodes.Call, context: InferenceContext | None = None, **kwargs: Any
-) -> Iterator[InferenceResult]:
+) -> Iterator[CopyResult]:
     assert isinstance(node.func, nodes.Attribute)
     inferred_orig, inferred_copy = itertools.tee(node.func.expr.infer(context=context))
     if all(
@@ -973,9 +995,9 @@ def _infer_copy_method(
         )
         for inferred_node in inferred_orig
     ):
-        return inferred_copy
+        return cast(Iterator[CopyResult], inferred_copy)
 
-    raise UseInferenceDefault()
+    raise UseInferenceDefault
 
 
 def _is_str_format_call(node: nodes.Call) -> bool:
@@ -1081,5 +1103,7 @@ def _infer_str_format_call(
 )
 
 AstroidManager().register_transform(
-    nodes.Call, inference_tip(_infer_str_format_call), _is_str_format_call
+    nodes.Call,
+    inference_tip(_infer_str_format_call),
+    _is_str_format_call,
 )

astroid/nodes/node_classes.py

@@ -1864,9 +1864,7 @@ def __init__(
             parent=parent,
         )
 
-    def postinit(
-        self, items: list[tuple[SuccessfulInferenceResult, SuccessfulInferenceResult]]
-    ) -> None:
+    def postinit(self, items: list[tuple[InferenceResult, InferenceResult]]) -> None:
         """Do some setup after initialisation.
 
         :param items: The key-value pairs contained in the dictionary.
@@ -4058,11 +4056,13 @@ class EvaluatedObject(NodeNG):
     _astroid_fields = ("original",)
     _other_fields = ("value",)
 
-    def __init__(self, original: NodeNG, value: NodeNG | util.UninferableBase) -> None:
-        self.original: NodeNG = original
+    def __init__(
+        self, original: SuccessfulInferenceResult, value: InferenceResult
+    ) -> None:
+        self.original: SuccessfulInferenceResult = original
         """The original node that has already been evaluated"""
 
-        self.value: NodeNG | util.UninferableBase = value
+        self.value: InferenceResult = value
         """The inferred value"""
 
         super().__init__(

astroid/rebuilder.py

@@ -22,7 +22,7 @@
 from astroid.manager import AstroidManager
 from astroid.nodes import NodeNG
 from astroid.nodes.utils import Position
-from astroid.typing import SuccessfulInferenceResult
+from astroid.typing import InferenceResult
 
 REDIRECT: Final[dict[str, str]] = {
     "arguments": "Arguments",
@@ -1019,7 +1019,7 @@ def visit_dict(self, node: ast.Dict, parent: NodeNG) -> nodes.Dict:
             end_col_offset=node.end_col_offset,
             parent=parent,
         )
-        items: list[tuple[SuccessfulInferenceResult, SuccessfulInferenceResult]] = list(
+        items: list[tuple[InferenceResult, InferenceResult]] = list(
             self._visit_dict_items(node, parent, newnode)
         )
         newnode.postinit(items)

astroid/typing.py

@@ -17,6 +17,8 @@
 )
 
 if TYPE_CHECKING:
+    from collections.abc import Iterator
+
     from astroid import bases, exceptions, nodes, transforms, util
     from astroid.context import InferenceContext
     from astroid.interpreter._import import spec
@@ -84,7 +86,7 @@ def __call__(
         node: _SuccessfulInferenceResultT_contra,
         context: InferenceContext | None = None,
         **kwargs: Any,
-    ) -> Generator[InferenceResult, None, None]:
+    ) -> Iterator[InferenceResult]:
         ...  # pragma: no cover
 
 

tests/test_nodes.py

@@ -1931,7 +1931,10 @@ def test_str_repr_no_warnings(node):
 
         if "int" in param_type.annotation:
             args[name] = random.randint(0, 50)
-        elif "NodeNG" in param_type.annotation:
+        elif (
+            "NodeNG" in param_type.annotation
+            or "SuccessfulInferenceResult" in param_type.annotation
+        ):
             args[name] = nodes.Unknown()
         elif "str" in param_type.annotation:
             args[name] = ""