[3.11] pythongh-96587: Raise SyntaxError for PEP654 on older feature_version (pythonGH-96588) (python#96591)

(cherry picked from commit 2c7d2e8)

Co-authored-by: Nikita Sobolev <mail@sobolevn.me>

Author: sobolevn

Grammar/python.gram

@@ -412,7 +412,9 @@ try_stmt[stmt_ty]:
     | invalid_try_stmt
     | 'try' &&':' b=block f=finally_block { _PyAST_Try(b, NULL, NULL, f, EXTRA) }
     | 'try' &&':' b=block ex[asdl_excepthandler_seq*]=except_block+ el=[else_block] f=[finally_block] { _PyAST_Try(b, ex, el, f, EXTRA) }
-    | 'try' &&':' b=block ex[asdl_excepthandler_seq*]=except_star_block+ el=[else_block] f=[finally_block] { _PyAST_TryStar(b, ex, el, f, EXTRA) }
+    | 'try' &&':' b=block ex[asdl_excepthandler_seq*]=except_star_block+ el=[else_block] f=[finally_block] { 
+        CHECK_VERSION(stmt_ty, 11, "Exception groups are", 
+                      _PyAST_TryStar(b, ex, el, f, EXTRA)) }
 
 
 # Except statement

Lib/test/test_ast.py

@@ -771,6 +771,15 @@ def test_assignment_expression_feature_version(self):
         with self.assertRaises(SyntaxError):
             ast.parse('(x := 0)', feature_version=(3, 7))
 
+    def test_exception_groups_feature_version(self):
+        code = dedent('''
+        try: ...
+        except* Exception: ...
+        ''')
+        ast.parse(code)
+        with self.assertRaises(SyntaxError):
+            ast.parse(code, feature_version=(3, 10))
+
     def test_constant_as_name(self):
         for constant in "True", "False", "None":
             expr = ast.Expression(ast.Name(constant, ast.Load()))

Misc/NEWS.d/next/Core and Builtins/2022-09-05-19-20-44.gh-issue-96587.bVxhX2.rst

@@ -0,0 +1,2 @@
+Correctly raise ``SyntaxError`` on exception groups (:pep:`654`) on python
+versions prior to 3.11