Commit e645c89b authored by Claude Paroz's avatar Claude Paroz
Browse files

[1.5.x] Fixed #14315 -- Made memcached backend handle negative incr/decr values 

Thanks Michael Manfre for the report and initial patch and
Tobias McNulty for the review.

Backport of 79dd751b from master.
parent 79209dfd

django/core/cache/backends/memcached.py

+6 −0
Original line number Diff line number Diff line
@@ -90,6 +90,9 @@ class BaseMemcachedCache(BaseCache): 


    def incr(self, key, delta=1, version=None):

        key = self.make_key(key, version=version)

        # memcached doesn't support a negative delta

        if delta < 0:

            return self._cache.decr(key, -delta)

        try:

            val = self._cache.incr(key, delta)
@@ -105,6 +108,9 @@ class BaseMemcachedCache(BaseCache): 


    def decr(self, key, delta=1, version=None):

        key = self.make_key(key, version=version)

        # memcached doesn't support a negative delta

        if delta < 0:

            return self._cache.incr(key, -delta)

        try:

            val = self._cache.decr(key, delta)

tests/regressiontests/cache/tests.py

+2 −0
Original line number Diff line number Diff line
@@ -257,6 +257,7 @@ class BaseCacheTests(object): 
        self.assertEqual(self.cache.get('answer'), 42)

        self.assertEqual(self.cache.incr('answer', 10), 52)

        self.assertEqual(self.cache.get('answer'), 52)

        self.assertEqual(self.cache.incr('answer', -10), 42)

        self.assertRaises(ValueError, self.cache.incr, 'does_not_exist')



    def test_decr(self):
@@ -266,6 +267,7 @@ class BaseCacheTests(object): 
        self.assertEqual(self.cache.get('answer'), 42)

        self.assertEqual(self.cache.decr('answer', 10), 32)

        self.assertEqual(self.cache.get('answer'), 32)

        self.assertEqual(self.cache.decr('answer', -10), 42)

        self.assertRaises(ValueError, self.cache.decr, 'does_not_exist')



    def test_data_types(self):