Fix for HSET argument validation to allow any non-None key

Fixes redis#1337
Fixes redis#1341

Author: AleksMat

CHANGES

@@ -1,3 +1,6 @@
+* 3.5.1 (May 9, 2020)
+    * Fix for HSET argument validation to allow any non-None key. Thanks
+      @AleksMat, #1337, #1341
 * 3.5.0 (April 29, 2020)
     * Removed exception trapping from __del__ methods. redis-py objects that
       hold various resources implement __del__ cleanup methods to release

redis/client.py

@@ -3034,14 +3034,14 @@ def hlen(self, name):
     def hset(self, name, key=None, value=None, mapping=None):
         """
         Set ``key`` to ``value`` within hash ``name``,
-        Use ``mappings`` keyword args to set multiple key/value pairs
-        for a hash ``name``.
+        ``mapping`` accepts a dict of key/value pairs that that will be
+        added to hash ``name``.
         Returns the number of fields that were added.
         """
-        if not key and not mapping:
+        if key is None and not mapping:
             raise DataError("'hset' with no key value pairs")
         items = []
-        if key:
+        if key is not None:
             items.extend((key, value))
         if mapping:
             for pair in mapping.items():

tests/test_commands.py

@@ -1612,6 +1612,10 @@ def test_hget_and_hset(self, r):
         # key inside of hash that doesn't exist returns null value
         assert r.hget('a', 'b') is None
 
+        # keys with bool(key) == False
+        assert r.hset('a', 0, 10) == 1
+        assert r.hset('a', '', 10) == 1
+
     def test_hset_with_multi_key_values(self, r):
         r.hset('a', mapping={'1': 1, '2': 2, '3': 3})
         assert r.hget('a', '1') == b'1'