[Python-checkins] bpo-31222: Make (datetime|date|time).replace return subclass type in Pure Python (#4176)

Thu Nov 9 16:34:36 EST 2017

https://github.com/python/cpython/commit/191e993365ac3206f46132dcf46236471ec54bfa
commit: 191e993365ac3206f46132dcf46236471ec54bfa
branch: master
author: Paul Ganssle <pganssle at users.noreply.github.com>
committer: Victor Stinner <victor.stinner at gmail.com>
date: 2017年11月09日T13:34:29-08:00
summary:
bpo-31222: Make (datetime|date|time).replace return subclass type in Pure Python (#4176)
files:
M Lib/datetime.py
M Lib/test/datetimetester.py

diff --git a/Lib/datetime.py b/Lib/datetime.py
index 2f03847be0a..67d8600921c 100644
--- a/Lib/datetime.py
+++ b/Lib/datetime.py
@@ -828,7 +828,7 @@ def replace(self, year=None, month=None, day=None):
 month = self._month
 if day is None:
 day = self._day
- return date(year, month, day)
+ return type(self)(year, month, day)
 
 # Comparisons of date objects with other.
 
@@ -1316,7 +1316,7 @@ def replace(self, hour=None, minute=None, second=None, microsecond=None,
 tzinfo = self.tzinfo
 if fold is None:
 fold = self._fold
- return time(hour, minute, second, microsecond, tzinfo, fold=fold)
+ return type(self)(hour, minute, second, microsecond, tzinfo, fold=fold)
 
 # Pickle support.
 
@@ -1597,7 +1597,7 @@ def replace(self, year=None, month=None, day=None, hour=None,
 tzinfo = self.tzinfo
 if fold is None:
 fold = self.fold
- return datetime(year, month, day, hour, minute, second,
+ return type(self)(year, month, day, hour, minute, second,
 microsecond, tzinfo, fold=fold)
 
 def _local_timezone(self):
diff --git a/Lib/test/datetimetester.py b/Lib/test/datetimetester.py
index c5f91fbe184..5b58e99fbcd 100644
--- a/Lib/test/datetimetester.py
+++ b/Lib/test/datetimetester.py
@@ -1520,6 +1520,13 @@ def test_replace(self):
 base = cls(2000, 2, 29)
 self.assertRaises(ValueError, base.replace, year=2001)
 
+ def test_subclass_replace(self):
+ class DateSubclass(self.theclass):
+ pass
+
+ dt = DateSubclass(2012, 1, 1)
+ self.assertIs(type(dt.replace(year=2013)), DateSubclass)
+
 def test_subclass_date(self):
 
 class C(self.theclass):
@@ -2626,6 +2633,13 @@ def test_replace(self):
 self.assertRaises(ValueError, base.replace, second=100)
 self.assertRaises(ValueError, base.replace, microsecond=1000000)
 
+ def test_subclass_replace(self):
+ class TimeSubclass(self.theclass):
+ pass
+
+ ctime = TimeSubclass(12, 30)
+ self.assertIs(type(ctime.replace(hour=10)), TimeSubclass)
+
 def test_subclass_time(self):
 
 class C(self.theclass):
