[pypy-commit] pypy default: Tests for the same situation with other set operations. Fix for

[arigo]

Author: Armin Rigo <arigo at tunes.org>
Branch: 
Changeset: r72408:e27d1225e4ca
Date: 2014-07-09 21:26 +0200
http://bitbucket.org/pypy/pypy/changeset/e27d1225e4ca/

Log:	Tests for the same situation with other set operations. Fix for
	symmetric_difference.

diff --git a/pypy/objspace/std/setobject.py b/pypy/objspace/std/setobject.py
--- a/pypy/objspace/std/setobject.py
+++ b/pypy/objspace/std/setobject.py
@@ -1060,10 +1060,14 @@
         return storage, strategy
 
     def symmetric_difference(self, w_set, w_other):
+        if w_other.length() == 0:
+            return w_set.copy_real()
         storage, strategy = self._symmetric_difference_base(w_set, w_other)
         return w_set.from_storage_and_strategy(storage, strategy)
 
     def symmetric_difference_update(self, w_set, w_other):
+        if w_other.length() == 0:
+            return
         storage, strategy = self._symmetric_difference_base(w_set, w_other)
         w_set.strategy = strategy
         w_set.sstorage = storage
diff --git a/pypy/objspace/std/test/test_setobject.py b/pypy/objspace/std/test/test_setobject.py
--- a/pypy/objspace/std/test/test_setobject.py
+++ b/pypy/objspace/std/test/test_setobject.py
@@ -967,3 +967,28 @@
         assert strategy(s) == "IntegerSetStrategy"
         s.update(set())
         assert strategy(s) == "IntegerSetStrategy"
+        #
+        s = set([1, 2, 3])
+        s |= set()
+        assert strategy(s) == "IntegerSetStrategy"
+        #
+        s = set([1, 2, 3]).difference(set())
+        assert strategy(s) == "IntegerSetStrategy"
+        #
+        s = set([1, 2, 3])
+        s.difference_update(set())
+        assert strategy(s) == "IntegerSetStrategy"
+        #
+        s = set([1, 2, 3]).symmetric_difference(set())
+        assert strategy(s) == "IntegerSetStrategy"
+        #
+        s = set([1, 2, 3])
+        s.symmetric_difference_update(set())
+        assert strategy(s) == "IntegerSetStrategy"
+        #
+        s = set([1, 2, 3]).intersection(set())
+        assert strategy(s) == "EmptySetStrategy"
+        #
+        s = set([1, 2, 3])
+        s.intersection_update(set())
+        assert strategy(s) == "EmptySetStrategy"