Issue #24731: Fixed crash on converting objects with special methods
__str__, __trunc__, and __float__ returning instances of subclasses of
str, long, and float to subclasses of str, long, and float correspondingly.
diff --git a/Lib/test/test_float.py b/Lib/test/test_float.py
index 4224306..4ec894c 100644
--- a/Lib/test/test_float.py
+++ b/Lib/test/test_float.py
@@ -27,6 +27,12 @@
test_dir = os.path.dirname(__file__) or os.curdir
format_testfile = os.path.join(test_dir, 'formatfloat_testcases.txt')
+class FloatSubclass(float):
+ pass
+
+class OtherFloatSubclass(float):
+ pass
+
class GeneralFloatCases(unittest.TestCase):
def test_float(self):
@@ -200,6 +206,15 @@
return ""
self.assertRaises(TypeError, time.sleep, Foo5())
+ # Issue #24731
+ class F:
+ def __float__(self):
+ return OtherFloatSubclass(42.)
+ self.assertAlmostEqual(float(F()), 42.)
+ self.assertIs(type(float(F())), OtherFloatSubclass)
+ self.assertAlmostEqual(FloatSubclass(F()), 42.)
+ self.assertIs(type(FloatSubclass(F())), FloatSubclass)
+
def test_is_integer(self):
self.assertFalse((1.1).is_integer())
self.assertTrue((1.).is_integer())