[3.12] gh-115881: Ensure `ast.parse()` parses conditional context managers even with...

diff --git a/Grammar/python.gram b/Grammar/python.gram
index a4fd3f27dba9449ed0c495487c183c3800a16cdc..19dd92de896d8c115e141bae69a06e71364b3b88 100644 (file)
--- a/Grammar/python.gram
+++ b/Grammar/python.gram
@@ -392,7 +392,7 @@ for_stmt[stmt_ty]:
 with_stmt[stmt_ty]:
     | invalid_with_stmt_indent
     | 'with' '(' a[asdl_withitem_seq*]=','.with_item+ ','? ')' ':' b=block {
-        CHECK_VERSION(stmt_ty, 9, "Parenthesized context managers are", _PyAST_With(a, b, NULL, EXTRA)) }
+        _PyAST_With(a, b, NULL, EXTRA) }
     | 'with' a[asdl_withitem_seq*]=','.with_item+ ':' tc=[TYPE_COMMENT] b=block {
         _PyAST_With(a, b, NEW_TYPE_COMMENT(p, tc), EXTRA) }
     | ASYNC 'with' '(' a[asdl_withitem_seq*]=','.with_item+ ','? ')' ':' b=block {

diff --git a/Lib/test/test_ast.py b/Lib/test/test_ast.py
index 9736208a92fc6e0b6610e1a1a68938affa6cceb9..a357fbfd228c025faefe5b544df71d26daf04211 100644 (file)
--- a/Lib/test/test_ast.py
+++ b/Lib/test/test_ast.py
@@ -1007,19 +1007,15 @@ class AST_Tests(unittest.TestCase):
         with self.assertRaises(SyntaxError):
             ast.parse('lambda x=1, /: ...', feature_version=(3, 7))
 
-    def test_parenthesized_with_feature_version(self):
-        ast.parse('with (CtxManager() as example): ...', feature_version=(3, 10))
-        # While advertised as a feature in Python 3.10, this was allowed starting 3.9
-        ast.parse('with (CtxManager() as example): ...', feature_version=(3, 9))
-        with self.assertRaises(SyntaxError):
-            ast.parse('with (CtxManager() as example): ...', feature_version=(3, 8))
-        ast.parse('with CtxManager() as example: ...', feature_version=(3, 8))
-
     def test_assignment_expression_feature_version(self):
         ast.parse('(x := 0)', feature_version=(3, 8))
         with self.assertRaises(SyntaxError):
             ast.parse('(x := 0)', feature_version=(3, 7))
 
+    def test_conditional_context_managers_parse_with_low_feature_version(self):
+        # regression test for gh-115881
+        ast.parse('with (x() if y else z()): ...', feature_version=(3, 8))
+
     def test_exception_groups_feature_version(self):
         code = dedent('''
         try: ...

diff --git a/Misc/NEWS.d/next/Library/2024-02-25-19-20-05.gh-issue-115881.ro_Kuw.rst b/Misc/NEWS.d/next/Library/2024-02-25-19-20-05.gh-issue-115881.ro_Kuw.rst
new file mode 100644 (file)
index 0000000..99bccb2
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2024-02-25-19-20-05.gh-issue-115881.ro_Kuw.rst
@@ -0,0 +1,4 @@
+Fix issue where :func:`ast.parse` would incorrectly flag conditional context\r
+managers (such as ``with (x() if y else z()): ...``) as invalid syntax if\r
+``feature_version=(3, 8)`` was passed. This reverts changes to the\r
+grammar made as part of gh-94949.\r

diff --git a/Parser/parser.c b/Parser/parser.c
index 25b4ead78191d3412eff0344f584b048e8c8de65..66eb6e6048934f38576e8682b3e7da16a8a9243b 100644 (file)
--- a/Parser/parser.c
+++ b/Parser/parser.c
@@ -6566,7 +6566,7 @@ with_stmt_rule(Parser *p)
             UNUSED(_end_lineno); // Only used by EXTRA macro
             int _end_col_offset = _token->end_col_offset;
             UNUSED(_end_col_offset); // Only used by EXTRA macro
-            _res = CHECK_VERSION ( stmt_ty , 9 , "Parenthesized context managers are" , _PyAST_With ( a , b , NULL , EXTRA ) );
+            _res = _PyAST_With ( a , b , NULL , EXTRA );
             if (_res == NULL && PyErr_Occurred()) {
                 p->error_indicator = 1;
                 p->level--;