implementing the LMOVE and BLMOVE commands (#1504)

Author: chayim

redis/client.py

@@ -581,8 +581,8 @@ class Redis:
     """
     RESPONSE_CALLBACKS = {
         **string_keys_to_dict(
-            'AUTH COPY EXPIRE EXPIREAT HEXISTS HMSET MOVE MSETNX PERSIST '
-            'PSETEX RENAMENX SISMEMBER SMOVE SETEX SETNX',
+            'AUTH COPY EXPIRE EXPIREAT HEXISTS HMSET LMOVE BLMOVE MOVE '
+            'MSETNX PERSIST PSETEX RENAMENX SISMEMBER SMOVE SETEX SETNX',
             bool
         ),
         **string_keys_to_dict(
@@ -1851,6 +1851,23 @@ def keys(self, pattern='*'):
         "Returns a list of keys matching ``pattern``"
         return self.execute_command('KEYS', pattern)
 
+    def lmove(self, first_list, second_list, src="LEFT", dest="RIGHT"):
+        """
+        Atomically returns and removes the first/last element of a list,
+        pushing it as the first/last element on the destination list.
+        Returns the element being popped and pushed.
+        """
+        params = [first_list, second_list, src, dest]
+        return self.execute_command("LMOVE", *params)
+
+    def blmove(self, first_list, second_list, timeout,
+               src="LEFT", dest="RIGHT"):
+        """
+        Blocking version of lmove.
+        """
+        params = [first_list, second_list, src, dest, timeout]
+        return self.execute_command("BLMOVE", *params)
+
     def mget(self, keys, *args):
         """
         Returns a list of values ordered identically to ``keys``

tests/test_commands.py

@@ -849,6 +849,18 @@ def test_mget(self, r):
         r['c'] = '3'
         assert r.mget('a', 'other', 'b', 'c') == [b'1', None, b'2', b'3']
 
+    @skip_if_server_version_lt('6.2.0')
+    def test_lmove(self, r):
+        r.rpush('a', 'one', 'two', 'three', 'four')
+        assert r.lmove('a', 'b')
+        assert r.lmove('a', 'b', 'right', 'left')
+
+    @skip_if_server_version_lt('6.2.0')
+    def test_blmove(self, r):
+        r.rpush('a', 'one', 'two', 'three', 'four')
+        assert r.blmove('a', 'b', 5)
+        assert r.blmove('a', 'b', 1, 'RIGHT', 'LEFT')
+
     def test_mset(self, r):
         d = {'a': b'1', 'b': b'2', 'c': b'3'}
         assert r.mset(d)