Fix false positive no-member in except * handler

Author: matusvalo

astroid/protocols.py

@@ -527,11 +527,21 @@ def excepthandler_assigned_stmts(
 ) -> Any:
     from astroid import objects  # pylint: disable=import-outside-toplevel
 
-    for assigned in node_classes.unpack_infer(self.type):
-        if isinstance(assigned, nodes.ClassDef):
-            assigned = objects.ExceptionInstance(assigned)
+    def _generate_assigned():
+        for assigned in node_classes.unpack_infer(self.type):
+            if isinstance(assigned, nodes.ClassDef):
+                assigned = objects.ExceptionInstance(assigned)
 
+            yield assigned
+
+    if isinstance(self.parent, node_classes.TryStar):
+        # except * handler has assigned ExceptionGroup
+        eg = nodes.ClassDef('ExceptionGroup', self.lineno, self.col_offset, self, end_lineno=self.end_lineno, end_col_offset=self.end_col_offset)
+        assigned = objects.ExceptionInstance(eg)
+        assigned.instance_attrs['exceptions'] = [nodes.List.from_elements(_generate_assigned())]
         yield assigned
+    else:
+        yield from _generate_assigned()
     return {
         "node": self,
         "unknown": node,

tests/test_group_exceptions.py

@@ -11,6 +11,7 @@
     For,
     Name,
     Try,
+    List,
     Uninferable,
     bases,
     extract_node,
@@ -93,6 +94,7 @@ def test_star_exceptions() -> None:
     assert final.value.args[0].value == 0
 
 
+
 @pytest.mark.skipif(not PY311_PLUS, reason="Requires Python 3.11 or higher")
 def test_star_exceptions_infer_name() -> None:
     trystar = extract_node(
@@ -108,3 +110,31 @@ def test_star_exceptions_infer_name() -> None:
     stmts = bases._infer_stmts([trystar], context)
     assert list(stmts) == [Uninferable]
     assert context.lookupname == name
+
+
+@pytest.mark.skipif(not PY311_PLUS, reason="Requires Python 3.11 or higher")
+def test_star_exceptions_infer_exceptions() -> None:
+    code = textwrap.dedent(
+        """
+    try:
+        raise ExceptionGroup("group", [ValueError(654), TypeError(10)])
+    except* ValueError as ve:
+        print(e.exceptions)
+    except* TypeError as te:
+        print(e.exceptions)
+    else:
+        sys.exit(127)
+    finally:
+        sys.exit(0)"""
+    )
+    node = extract_node(code)
+    assert isinstance(node, TryStar)
+    inferred_ve = next(node.handlers[0].statement().name.infer())
+    assert inferred_ve.name =='ExceptionGroup'
+    assert isinstance(inferred_ve.getattr('exceptions')[0], List)
+    assert inferred_ve.getattr('exceptions')[0].elts[0].pytype() == 'builtins.ValueError'
+
+    inferred_te = next(node.handlers[1].statement().name.infer())
+    assert inferred_te.name =='ExceptionGroup'
+    assert isinstance(inferred_te.getattr('exceptions')[0], List)
+    assert inferred_te.getattr('exceptions')[0].elts[0].pytype() == 'builtins.TypeError'