Fix crash: key expire while search (#2270)

* fix expire while search

* sleep

Author: dvora-h

redis/commands/search/result.py

@@ -38,7 +38,7 @@ def __init__(
             score = float(res[i + 1]) if with_scores else None
 
             fields = {}
-            if hascontent:
+            if hascontent and res[i + fields_offset] is not None:
                 fields = (
                     dict(
                         dict(

tests/test_search.py

@@ -1698,3 +1698,17 @@ def test_dialect(modclient: redis.Redis):
     with pytest.raises(redis.ResponseError) as err:
         modclient.ft().explain(Query("@title:(@num:[0 10])").dialect(2))
     assert "Syntax error" in str(err)
+
+
+@pytest.mark.redismod
+def test_expire_while_search(modclient: redis.Redis):
+    modclient.ft().create_index((TextField("txt"),))
+    modclient.hset("hset:1", "txt", "a")
+    modclient.hset("hset:2", "txt", "b")
+    modclient.hset("hset:3", "txt", "c")
+    assert 3 == modclient.ft().search(Query("*")).total
+    modclient.pexpire("hset:2", 300)
+    for _ in range(500):
+        modclient.ft().search(Query("*")).docs[1]
+    time.sleep(1)
+    assert 2 == modclient.ft().search(Query("*")).total