False positive unsubscriptable-object (#2307) (#2309)

Fix a regression in 2.15.7 for ``unsubscriptable-object``.

Raise an `InferenceError` when there is a `SyntaxError` due to an invalid `TypeVar` name.
This reverts commit 89dfb48.

Closes #2305
Closes pylint-dev/pylint#9069

(cherry picked from commit 1f0f2f8)

Co-authored-by: Mark Byrne <[email protected]>

ChangeLog

@@ -7,6 +7,16 @@ What's New in astroid 2.15.8?
 Release date: TBA
 
 
+What's New in astroid 2.15.8?
+=============================
+Release date: TBA
+
+* Fix a regression in 2.15.7 for ``unsubscriptable-object``.
+
+  Closes #2305
+  Closes pylint-dev/pylint#9069
+
+
 What's New in astroid 2.15.7?
 =============================
 Release date: 2023-09-23

astroid/brain/brain_typing.py

@@ -15,6 +15,7 @@
 from astroid.builder import _extract_single_node
 from astroid.const import PY38_PLUS, PY39_PLUS
 from astroid.exceptions import (
+    AstroidSyntaxError,
     AttributeInferenceError,
     InferenceError,
     UseInferenceDefault,
@@ -139,14 +140,10 @@ def infer_typing_typevar_or_newtype(
         raise UseInferenceDefault
 
     typename = node.args[0].as_string().strip("'")
-    node = ClassDef(
-        name=typename,
-        lineno=node.lineno,
-        col_offset=node.col_offset,
-        parent=node.parent,
-        end_lineno=node.end_lineno,
-        end_col_offset=node.end_col_offset,
-    )
+    try:
+        node = extract_node(TYPING_TYPE_TEMPLATE.format(typename))
+    except AstroidSyntaxError as exc:
+        raise InferenceError from exc
     return node.infer(context=context_itton)
 
 

tests/brain/test_typing.py

@@ -5,7 +5,10 @@
 # For details: https://github.com/pylint-dev/astroid/blob/main/LICENSE
 # Copyright (c) https://github.com/pylint-dev/astroid/blob/main/CONTRIBUTORS.txt
 
-from astroid import builder, nodes
+import pytest
+
+from astroid import builder
+from astroid.exceptions import InferenceError
 
 
 def test_infer_typevar() -> None:
@@ -15,13 +18,11 @@ def test_infer_typevar() -> None:
     Test that an inferred `typing.TypeVar()` call produces a `nodes.ClassDef`
     node.
     """
-    assign_node = builder.extract_node(
+    call_node = builder.extract_node(
         """
     from typing import TypeVar
-    MyType = TypeVar('My.Type')
+    TypeVar('My.Type')
     """
     )
-    call = assign_node.value
-    inferred = next(call.infer())
-    assert isinstance(inferred, nodes.ClassDef)
-    assert inferred.name == "My.Type"
+    with pytest.raises(InferenceError):
+        call_node.inferred()