Issue #9128: Validate class decorator syntax correctly in parser module.

Lib/test/test_parser.py

@@ -180,6 +180,14 @@ class RoundtripLegalSyntaxTestCase(unittest.TestCase):
 
     def test_class_defs(self):
         self.check_suite("class foo():pass")
+        self.check_suite("@class_decorator\n"
+                         "class foo():pass")
+        self.check_suite("@class_decorator(arg)\n"
+                         "class foo():pass")
+        self.check_suite("@decorator1\n"
+                         "@decorator2\n"
+                         "class foo():pass")
+
 
     def test_import_from_statement(self):
         self.check_suite("from sys.path import *")

Misc/NEWS

@@ -16,6 +16,7 @@ Core and Builtins
 Library
 -------
 
+- Issue #9128: Fix validation of class decorators in parser module.
 
 Extension Modules
 -----------------

Modules/parsermodule.c

@@ -2682,14 +2682,15 @@ validate_funcdef(node *tree)
 static int
 validate_decorated(node *tree)
 {
-  int nch = NCH(tree);
-  int ok = (validate_ntype(tree, decorated)
-            && (nch == 2)
-            && validate_decorators(RCHILD(tree, -2))
-            && (validate_funcdef(RCHILD(tree, -1))
-                || validate_class(RCHILD(tree, -1)))
-            );
-  return ok;
+    int nch = NCH(tree);
+    int ok = (validate_ntype(tree, decorated)
+              && (nch == 2)
+              && validate_decorators(RCHILD(tree, -2)));
+    if (TYPE(RCHILD(tree, -1)) == funcdef)
+        ok = ok && validate_funcdef(RCHILD(tree, -1));
+    else
+        ok = ok && validate_class(RCHILD(tree, -1));
+    return ok;
 }
 
 static int