fix: limit parsing in zrange commands (#3626)

1. The offset value can be negative, in that case we should return an empty array.
2. Fix edge cases of inf*0 and -inf + inf, so they will result in 0 and non NaN (similarily to Valkey).

Signed-off-by: Roman Gershman <roman@dragonflydb.io>

.github/workflows/test-fakeredis.yml

@@ -67,14 +67,14 @@ jobs:
           echo "-----------------------------"
 
           # The order of redirect is important
-          ./dragonfly --proactor_threads=4 --dbfilename=   --noversion_check --port=6380  \
+          ./dragonfly --proactor_threads=4  --noversion_check --port=6380  \
            --lua_resp2_legacy_float 1> /tmp/dragonfly.log 2>&1 &
 
       - name: Run tests
         working-directory: tests/fakeredis
         run: |
           poetry run pytest test/ --ignore test/test_hypothesis.py  --ignore test/test_json/ \
-            --ignore test_bitmap_commands.py --ignore test/test_mixins/  \
+            --ignore test_bitmap_commands.py \
             --junit-xml=results-tests.xml  --html=report-tests.html -v
         continue-on-error: true  # For now to mark the flow as successful
 

src/facade/facade_test.cc

@@ -81,6 +81,9 @@ void RespMatcher::DescribeTo(std::ostream* os) const {
     case RespExpr::ARRAY:
       *os << "array of length " << exp_int_;
       break;
+    case RespExpr::DOUBLE:
+      *os << exp_double_;
+      break;
     default:
       *os << "TBD";
       break;

src/server/zset_family.cc

@@ -731,6 +731,8 @@ ScoredMap FromObject(const CompactObj& co, double weight) {
 
   for (auto& elem : arr) {
     elem.second *= weight;
+    if (isnan(elem.second))
+      elem.second = 0;
     res.emplace(std::move(elem));
   }
 
@@ -749,7 +751,8 @@ ScoredMap ScoreMapFromSet(const PrimeValue& pv, double weight) {
 double Aggregate(double v1, double v2, AggType atype) {
   switch (atype) {
     case AggType::SUM:
-      return v1 + v2;
+      v1 += v2;
+      return isnan(v1) ? 0 : v1;
     case AggType::MAX:
       return max(v1, v2);
     case AggType::MIN:
@@ -2161,15 +2164,21 @@ void ZSetFamily::ZRangeGeneric(CmdArgList args, ConnectionContext* cntx, RangePa
     }
 
     if (parser.Check("LIMIT")) {
-      int64_t limit;
-      tie(range_params.offset, limit) = parser.Next<uint32_t, int64_t>();
+      auto [offset, limit] = parser.Next<int32_t, int32_t>();
+
       range_params.limit = limit < 0 ? UINT32_MAX : static_cast<uint32_t>(limit);
+      range_params.offset = offset < 0 ? UINT32_MAX : static_cast<uint32_t>(offset);
       continue;
     }
 
     return cntx->SendError(absl::StrCat("unsupported option ", parser.Peek()));
   }
 
+  if (range_params.offset == UINT32_MAX) {
+    auto* rb = static_cast<RedisReplyBuilder*>(cntx->reply_builder());
+    return rb->SendEmptyArray();
+  }
+
   ZRangeInternal(args.subspan(0, 3), range_params, cntx);
 }
 

src/server/zset_family_test.cc

@@ -637,6 +637,19 @@ TEST_F(ZSetFamilyTest, ZUnionStoreOpts) {
   ASSERT_THAT(resp, IntArg(3));
   resp = Run({"zrange", "max", "0", "-1", "withscores"});
   EXPECT_THAT(resp.GetVec(), ElementsAre("c", "0", "a", "2", "b", "4"));
+
+  // Check that infinity is handled correctly.
+  Run({"ZADD", "src1", "inf", "x"});
+  Run({"ZADD", "src2", "inf", "x"});
+  Run({"ZUNIONSTORE", "dest", "2", "src1", "src2", "WEIGHTS", "1.0", "0.0"});
+  resp = Run({"ZSCORE", "dest", "x"});
+  EXPECT_THAT(resp, DoubleArg(numeric_limits<double>::infinity()));
+
+  Run({"ZADD", "foo", "inf", "e1"});
+  Run({"ZADD", "bar", "-inf", "e1", "0.0", "e2"});
+  Run({"ZUNIONSTORE", "dest", "3", "foo", "bar", "foo"});
+  resp = Run({"ZSCORE", "dest", "e1"});
+  EXPECT_THAT(resp, DoubleArg(0));
 }
 
 TEST_F(ZSetFamilyTest, ZInterStore) {
@@ -1143,6 +1156,9 @@ TEST_F(ZSetFamilyTest, RangeLimit) {
 
   resp = Run({"ZRANGEBYSCORE", "", "0.0", "0.0", "foo"});
   EXPECT_THAT(resp, ErrArg("unsupported option"));
+
+  resp = Run({"ZRANGEBYLEX", "foo", "-", "+", "LIMIT", "-1", "3"});
+  EXPECT_THAT(resp, ArrLen(0));
 }
 
 }  // namespace dfly

tests/fakeredis/test/test_mixins/test_scripting.py

@@ -591,6 +591,7 @@ def test_lua_log_different_types(r, caplog):
     ]
 
 
+@pytest.mark.unsupported_server_types("dragonfly")
 def test_lua_log_wrong_level(r: redis.Redis):
     script = "redis.log(10, 'string')"
     script = r.register_script(script)