Multi-arg form for set.difference() and set.difference_update().
diff --git a/Lib/test/test_set.py b/Lib/test/test_set.py
index b32d953..1b01954 100644
--- a/Lib/test/test_set.py
+++ b/Lib/test/test_set.py
@@ -149,6 +149,8 @@
self.assertEqual(self.thetype('abcba').difference(C('efgfe')), set('abc'))
self.assertEqual(self.thetype('abcba').difference(C('ccb')), set('a'))
self.assertEqual(self.thetype('abcba').difference(C('ef')), set('abc'))
+ self.assertEqual(self.thetype('abcba').difference(), set('abc'))
+ self.assertEqual(self.thetype('abcba').difference(C('a'), C('b')), set('c'))
def test_sub(self):
i = self.s.difference(self.otherword)
@@ -467,6 +469,18 @@
self.assertEqual(s.difference_update(C(p)), None)
self.assertEqual(s, set(q))
+ s = self.thetype('abcdefghih')
+ s.difference_update()
+ self.assertEqual(s, self.thetype('abcdefghih'))
+
+ s = self.thetype('abcdefghih')
+ s.difference_update(C('aba'))
+ self.assertEqual(s, self.thetype('cdefghih'))
+
+ s = self.thetype('abcdefghih')
+ s.difference_update(C('cdc'), C('aba'))
+ self.assertEqual(s, self.thetype('efghih'))
+
def test_isub(self):
self.s -= set(self.otherword)
for c in (self.word + self.otherword):