From c6b31061997526b31961ec34328408ca421f51fc Mon Sep 17 00:00:00 2001 From: Xtreak Date: Sun, 14 Jul 2019 15:43:59 +0530 Subject: [PATCH] [3.7] bpo-37579: Improve equality behavior for pure Python datetime and time (GH-14726) (GH-14745) 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](https://bugs.python.org/issue37579) (cherry picked from commit e6b46aafad3427463d6264a68824df4797e682f1) Co-authored-by: Xtreak https://bugs.python.org/issue37579 --- Lib/datetime.py | 4 ++-- Lib/test/datetimetester.py | 20 +++++++++++++++++++ .../2019-07-13-10-59-43.bpo-37579.B1Tq9i.rst | 4 ++++ 3 files changed, 26 insertions(+), 2 deletions(-) create mode 100644 Misc/NEWS.d/next/Library/2019-07-13-10-59-43.bpo-37579.B1Tq9i.rst diff --git a/Lib/datetime.py b/Lib/datetime.py index a964b202e3c7..03beb055a00b 100644 --- a/Lib/datetime.py +++ b/Lib/datetime.py @@ -718,7 +718,7 @@ class timedelta: if isinstance(other, timedelta): return self._cmp(other) == 0 else: - return False + return NotImplemented def __le__(self, other): if isinstance(other, timedelta): @@ -1261,7 +1261,7 @@ class time: if isinstance(other, time): return self._cmp(other, allow_mixed=True) == 0 else: - return False + return NotImplemented def __le__(self, other): if isinstance(other, time): diff --git a/Lib/test/datetimetester.py b/Lib/test/datetimetester.py index 2f8975d8c07f..581441738658 100644 --- a/Lib/test/datetimetester.py +++ b/Lib/test/datetimetester.py @@ -53,6 +53,19 @@ OTHERSTUFF = (10, 34.5, "abc", {}, [], ()) 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 @@ class HarmlessMixedComparison: 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) diff --git a/Misc/NEWS.d/next/Library/2019-07-13-10-59-43.bpo-37579.B1Tq9i.rst b/Misc/NEWS.d/next/Library/2019-07-13-10-59-43.bpo-37579.B1Tq9i.rst new file mode 100644 index 000000000000..ad52cf2a06cc --- /dev/null +++ b/Misc/NEWS.d/next/Library/2019-07-13-10-59-43.bpo-37579.B1Tq9i.rst @@ -0,0 +1,4 @@ +Return :exc:`NotImplemented` in Python implementation of ``__eq__`` for +:class:`~datetime.timedelta` and :class:`~datetime.time` when the other +object being compared is not of the same type to match C implementation. +Patch by Karthikeyan Singaravelan. -- 2.47.3