[fix] Fix crash when inferring namedtuple with invalid field name (#2806)

Co-authored-by: Patcher <[email protected]>
Co-authored-by: Pierre Sassoulas <[email protected]>

Author: 3 people

ChangeLog

@@ -7,6 +7,10 @@ What's New in astroid 4.0.0?
 ============================
 Release date: TBA
 
+* Fix crash when inferring namedtuple with invalid field name looking like f-string formatting.
+
+  Closes #2519
+
 * Fix false positive no-member in except * handler.
 
   Closes pylint-dev/pylint#9056

astroid/exceptions.py

@@ -64,7 +64,10 @@ def __init__(self, message: str = "", **kws: Any) -> None:
             setattr(self, key, value)
 
     def __str__(self) -> str:
-        return self.message.format(**vars(self))
+        try:
+            return self.message.format(**vars(self))
+        except ValueError:
+            return self.message  # Return raw message if formatting fails
 
 
 class AstroidBuildingError(AstroidError):

tests/test_regrtest.py

@@ -550,3 +550,14 @@ def test_regression_infer_dict_literal_comparison_uninferable() -> None:
     node = extract_node("{{}}>0")
     inferred = next(node.infer())
     assert inferred.value == Uninferable
+
+
+def test_regression_infer_namedtuple_invalid_fieldname_error() -> None:
+    """Regression test for issue #2519."""
+    code = """
+    from collections import namedtuple
+    namedtuple('a','}')
+    """
+    node = extract_node(code)
+    inferred = next(node.infer())
+    assert inferred.value == Uninferable