From 6015cc50bc38b9e920ce4986ee10658eaa14f561 Mon Sep 17 00:00:00 2001 From: Serhiy Storchaka Date: Sun, 28 Oct 2018 13:43:03 +0200 Subject: [PATCH] bpo-32892: Support subclasses of base types in isinstance checks for AST constants. (GH-9934) Some projects (e.g. Chameleon) create ast.Str containing an instance of the str subclass. --- Lib/ast.py | 2 +- Lib/test/test_ast.py | 4 ++++ 2 files changed, 5 insertions(+), 1 deletion(-) diff --git a/Lib/ast.py b/Lib/ast.py index de3df1473e..4c8c7795ff 100644 --- a/Lib/ast.py +++ b/Lib/ast.py @@ -346,7 +346,7 @@ class _ABC(type): except AttributeError: return False else: - return type(value) in _const_types[cls] + return isinstance(value, _const_types[cls]) return type.__instancecheck__(cls, inst) def _new(cls, *args, **kwargs): diff --git a/Lib/test/test_ast.py b/Lib/test/test_ast.py index 10be02eee0..4bbdc3b82d 100644 --- a/Lib/test/test_ast.py +++ b/Lib/test/test_ast.py @@ -399,6 +399,10 @@ class AST_Tests(unittest.TestCase): self.assertFalse(isinstance(ast.Constant(), ast.NameConstant)) self.assertFalse(isinstance(ast.Constant(), ast.Ellipsis)) + class S(str): pass + self.assertTrue(isinstance(ast.Constant(S('42')), ast.Str)) + self.assertFalse(isinstance(ast.Constant(S('42')), ast.Num)) + def test_subclasses(self): class N(ast.Num): def __init__(self, *args, **kwargs): -- 2.40.0