bpo-37579: Improve equality behavior for pure Python datetime and time (GH-14726)
Returns NotImplemented for timedelta and time in __eq__ for different types in Python implementation, which matches the C implementation.
This also adds tests to enforce that these objects will fall back to the right hand side's __eq__ and/or __ne__ implementation.
bpo-37579
diff --git a/Lib/test/datetimetester.py b/Lib/test/datetimetester.py
index 53de065..37ddd4b 100644
--- a/Lib/test/datetimetester.py
+++ b/Lib/test/datetimetester.py
@@ -53,6 +53,19 @@
INF = float("inf")
NAN = float("nan")
+
+class ComparesEqualClass(object):
+ """
+ A class that is always equal to whatever you compare it to.
+ """
+
+ def __eq__(self, other):
+ return True
+
+ def __ne__(self, other):
+ return False
+
+
#############################################################################
# module tests
@@ -399,6 +412,13 @@
self.assertIn(me, [1, 20, [], me])
self.assertIn([], [me, 1, 20, []])
+ # Comparison to objects of unsupported types should return
+ # NotImplemented which falls back to the right hand side's __eq__
+ # method. In this case, ComparesEqualClass.__eq__ always returns True.
+ # ComparesEqualClass.__ne__ always returns False.
+ self.assertTrue(me == ComparesEqualClass())
+ self.assertFalse(me != ComparesEqualClass())
+
def test_harmful_mixed_comparison(self):
me = self.theclass(1, 1, 1)