Create ``UninferableBase``

5 files changed, 25 insertions, 24 deletions

diff --git a/astroid/brain/brain_builtin_inference.py b/astroid/brain/brain_builtin_inference.py
index b51d63a5..764ea3d6 100644
--- a/astroid/brain/brain_builtin_inference.py
+++ b/astroid/brain/brain_builtin_inference.py
@@ -209,10 +209,10 @@ def _container_generic_inference(node, context, node_type, transform):
             inferred = next(arg.infer(context=context))
         except (InferenceError, StopIteration) as exc:
             raise UseInferenceDefault from exc
-        if inferred is util.Uninferable:
+        if isinstance(inferred, util.UninferableBase):
             raise UseInferenceDefault
         transformed = transform(inferred)
-    if not transformed or transformed is util.Uninferable:
+    if not transformed or isinstance(transformed, util.UninferableBase):
         raise UseInferenceDefault
     return transformed
 
@@ -423,7 +423,9 @@ def infer_super(node, context: InferenceContext | None = None):
         except (InferenceError, StopIteration) as exc:
             raise UseInferenceDefault from exc
 
-    if mro_pointer is util.Uninferable or mro_type is util.Uninferable:
+    if isinstance(mro_pointer, util.UninferableBase) or isinstance(
+        mro_type, util.UninferableBase
+    ):
         # No way we could understand this.
         raise UseInferenceDefault
 
@@ -445,7 +447,7 @@ def _infer_getattr_args(node, context):
     except (InferenceError, StopIteration) as exc:
         raise UseInferenceDefault from exc
 
-    if obj is util.Uninferable or attr is util.Uninferable:
+    if isinstance(obj, util.UninferableBase) or isinstance(attr, util.UninferableBase):
         # If one of the arguments is something we can't infer,
         # then also make the result of the getattr call something
         # which is unknown.
@@ -467,8 +469,8 @@ def infer_getattr(node, context: InferenceContext | None = None):
     """
     obj, attr = _infer_getattr_args(node, context)
     if (
-        obj is util.Uninferable
-        or attr is util.Uninferable
+        isinstance(obj, util.UninferableBase)
+        or isinstance(attr, util.UninferableBase)
         or not hasattr(obj, "igetattr")
     ):
         return util.Uninferable
@@ -498,8 +500,8 @@ def infer_hasattr(node, context: InferenceContext | None = None):
     try:
         obj, attr = _infer_getattr_args(node, context)
         if (
-            obj is util.Uninferable
-            or attr is util.Uninferable
+            isinstance(obj, util.UninferableBase)
+            or isinstance(attr, util.UninferableBase)
             or not hasattr(obj, "getattr")
         ):
             return util.Uninferable
@@ -530,7 +532,7 @@ def infer_callable(node, context: InferenceContext | None = None):
         inferred = next(argument.infer(context=context))
     except (InferenceError, StopIteration):
         return util.Uninferable
-    if inferred is util.Uninferable:
+    if isinstance(inferred, util.UninferableBase):
         return util.Uninferable
     return nodes.Const(inferred.callable())
 
@@ -585,11 +587,11 @@ def infer_bool(node, context: InferenceContext | None = None):
         inferred = next(argument.infer(context=context))
     except (InferenceError, StopIteration):
         return util.Uninferable
-    if inferred is util.Uninferable:
+    if isinstance(inferred, util.UninferableBase):
         return util.Uninferable
 
     bool_value = inferred.bool_value(context=context)
-    if bool_value is util.Uninferable:
+    if isinstance(bool_value, util.UninferableBase):
         return util.Uninferable
     return nodes.Const(bool_value)
 
@@ -611,7 +613,7 @@ def infer_slice(node, context: InferenceContext | None = None):
     infer_func = partial(helpers.safe_infer, context=context)
     args = [infer_func(arg) for arg in args]
     for arg in args:
-        if not arg or arg is util.Uninferable:
+        if not arg or isinstance(arg, util.UninferableBase):
             raise UseInferenceDefault
         if not isinstance(arg, nodes.Const):
             raise UseInferenceDefault
@@ -725,7 +727,7 @@ def infer_isinstance(callnode, context: InferenceContext | None = None):
         raise UseInferenceDefault("TypeError: " + str(exc)) from exc
     except MroError as exc:
         raise UseInferenceDefault from exc
-    if isinstance_bool is util.Uninferable:
+    if isinstance(isinstance_bool, util.UninferableBase):
         raise UseInferenceDefault
     return nodes.Const(isinstance_bool)
 
@@ -811,7 +813,7 @@ def infer_int(node, context: InferenceContext | None = None):
         except (InferenceError, StopIteration) as exc:
             raise UseInferenceDefault(str(exc)) from exc
 
-        if first_value is util.Uninferable:
+        if isinstance(first_value, util.UninferableBase):
             raise UseInferenceDefault
 
         if isinstance(first_value, nodes.Const) and isinstance(
@@ -924,7 +926,7 @@ def _is_str_format_call(node: nodes.Call) -> bool:
 
 def _infer_str_format_call(
     node: nodes.Call, context: InferenceContext | None = None
-) -> Iterator[nodes.Const | type[util.Uninferable]]:
+) -> Iterator[nodes.Const | util.UninferableBase]:
     """Return a Const node based on the template and passed arguments."""
     call = arguments.CallSite.from_call(node, context=context)
     if isinstance(node.func.expr, nodes.Name):
diff --git a/astroid/brain/brain_dataclasses.py b/astroid/brain/brain_dataclasses.py
index a2e7adfa..1397ed14 100644
--- a/astroid/brain/brain_dataclasses.py
+++ b/astroid/brain/brain_dataclasses.py
@@ -25,7 +25,7 @@ from astroid.exceptions import AstroidSyntaxError, InferenceError, UseInferenceD
 from astroid.inference_tip import inference_tip
 from astroid.manager import AstroidManager
 from astroid.typing import InferenceResult
-from astroid.util import Uninferable
+from astroid.util import Uninferable, UninferableBase
 
 if sys.version_info >= (3, 8):
     from typing import Literal
@@ -446,7 +446,7 @@ def _looks_like_dataclass_decorator(
     except (InferenceError, StopIteration):
         inferred = Uninferable
 
-    if inferred is Uninferable:
+    if isinstance(inferred, UninferableBase):
         if isinstance(node, nodes.Name):
             return node.name in decorator_names
         if isinstance(node, nodes.Attribute):
@@ -594,7 +594,7 @@ _INFERABLE_TYPING_TYPES = frozenset(
 
 def _infer_instance_from_annotation(
     node: nodes.NodeNG, ctx: context.InferenceContext | None = None
-) -> Iterator[type[Uninferable] | bases.Instance]:
+) -> Iterator[UninferableBase | bases.Instance]:
     """Infer an instance corresponding to the type annotation represented by node.
 
     Currently has limited support for the typing module.
diff --git a/astroid/brain/brain_functools.py b/astroid/brain/brain_functools.py
index ffdbc888..f6a9830d 100644
--- a/astroid/brain/brain_functools.py
+++ b/astroid/brain/brain_functools.py
@@ -18,7 +18,7 @@ from astroid.interpreter import objectmodel
 from astroid.manager import AstroidManager
 from astroid.nodes.node_classes import AssignName, Attribute, Call, Name
 from astroid.nodes.scoped_nodes import FunctionDef
-from astroid.util import Uninferable
+from astroid.util import UninferableBase
 
 LRU_CACHE = "functools.lru_cache"
 
@@ -84,7 +84,7 @@ def _functools_partial_inference(
         inferred_wrapped_function = next(partial_function.infer(context=context))
     except (InferenceError, StopIteration) as exc:
         raise UseInferenceDefault from exc
-    if inferred_wrapped_function is Uninferable:
+    if isinstance(inferred_wrapped_function, UninferableBase):
         raise UseInferenceDefault("Cannot infer the wrapped function")
     if not isinstance(inferred_wrapped_function, FunctionDef):
         raise UseInferenceDefault("The wrapped function is not a function")
diff --git a/astroid/brain/brain_namedtuple_enum.py b/astroid/brain/brain_namedtuple_enum.py
index f9141629..36b70361 100644
--- a/astroid/brain/brain_namedtuple_enum.py
+++ b/astroid/brain/brain_namedtuple_enum.py
@@ -52,13 +52,13 @@ TYPING_NAMEDTUPLE_BASENAMES: Final = {
 
 
 def _infer_first(node, context):
-    if node is util.Uninferable:
+    if isinstance(node, util.UninferableBase):
         raise UseInferenceDefault
     try:
         value = next(node.infer(context=context))
     except StopIteration as exc:
         raise InferenceError from exc
-    if value is util.Uninferable:
+    if isinstance(value, util.UninferableBase):
         raise UseInferenceDefault()
     return value
 
diff --git a/astroid/brain/brain_typing.py b/astroid/brain/brain_typing.py
index b11bfa19..e0a9dfd1 100644
--- a/astroid/brain/brain_typing.py
+++ b/astroid/brain/brain_typing.py
@@ -33,7 +33,6 @@ from astroid.nodes.node_classes import (
     Tuple,
 )
 from astroid.nodes.scoped_nodes import ClassDef, FunctionDef
-from astroid.util import Uninferable
 
 if sys.version_info >= (3, 8):
     from typing import Final
@@ -297,7 +296,7 @@ def infer_typing_alias(
         col_offset=assign_name.col_offset,
         parent=node.parent,
     )
-    if res != Uninferable and isinstance(res, ClassDef):
+    if isinstance(res, ClassDef):
         # Only add `res` as base if it's a `ClassDef`
         # This isn't the case for `typing.Pattern` and `typing.Match`
         class_def.postinit(bases=[res], body=[], decorators=None)