Fix false positive no-member in except * handler

Author: matusvalo

ChangeLog

@@ -7,6 +7,10 @@ What's New in astroid 4.0.0?
 ============================
 Release date: TBA
 
+* Fix false positive no-member in except * handler.
+
+  Closes pylint-dev/pylint#9056
+
 * Fix crash when comparing invalid dict literal
 
   Closes #2522

astroid/protocols.py

@@ -15,6 +15,7 @@
 from typing import TYPE_CHECKING, Any, TypeVar
 
 from astroid import bases, decorators, nodes, util
+from astroid.builder import extract_node
 from astroid.const import Context
 from astroid.context import InferenceContext, copy_context
 from astroid.exceptions import (
@@ -527,11 +528,34 @@ 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 with caught
+        # exceptions under exceptions attribute
+        # pylint: disable-next=stop-iteration-return
+        eg = next(
+            node_classes.unpack_infer(
+                extract_node(
+                    """
+from builtins import ExceptionGroup
+ExceptionGroup
+"""
+                )
+            )
+        )
+        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

@@ -9,6 +9,7 @@
     AssignName,
     ExceptHandler,
     For,
+    List,
     Name,
     Try,
     Uninferable,
@@ -108,3 +109,33 @@ 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"