From 4c6ffd51250076f934cc4029bc2bc23579b286b8 Mon Sep 17 00:00:00 2001
From: yzc-yzc <96833212+yzc-yzc@users.noreply.github.com>
Date: Fri, 20 Jun 2025 13:51:52 +0800
Subject: [PATCH] Fix negative offset issue for ZRANGEBY[SCORE|LEX] command
 (#14043)

Fix #13952

This PR ensures that ZRANGE_SCORE/LEX command with a negative offset
will return empty.
---
 src/t_zset.c             |  8 +++++++-
 tests/unit/type/zset.tcl | 10 +++++++++-
 2 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/src/t_zset.c b/src/t_zset.c
index 8533ff12b..3379a8f01 100644
--- a/src/t_zset.c
+++ b/src/t_zset.c
@@ -3277,7 +3277,7 @@ void genericZrangebyscoreCommand(zrange_result_handler *handler,
     handler->beginResultEmission(handler, -1);
 
     /* For invalid offset, return directly. */
-    if (offset > 0 && offset >= (long)zsetLength(zobj)) {
+    if (offset < 0 || (offset > 0 && offset >= (long)zsetLength(zobj))) {
         handler->finalizeResultEmission(handler, 0);
         return;
     }
@@ -3551,6 +3551,12 @@ void genericZrangebylexCommand(zrange_result_handler *handler,
 
     handler->beginResultEmission(handler, -1);
 
+    /* For invalid offset, return directly. */
+    if (offset < 0 || (offset > 0 && offset >= (long)zsetLength(zobj))) {
+        handler->finalizeResultEmission(handler, 0);
+        return;
+    }
+
     if (zobj->encoding == OBJ_ENCODING_LISTPACK) {
         unsigned char *zl = zobj->ptr;
         unsigned char *eptr, *sptr;
diff --git a/tests/unit/type/zset.tcl b/tests/unit/type/zset.tcl
index dc0554d84..9eb1ea86d 100644
--- a/tests/unit/type/zset.tcl
+++ b/tests/unit/type/zset.tcl
@@ -583,20 +583,24 @@ start_server {tags {"zset"}} {
             assert_equal {d e f} [r zrangebyscore zset 0 10 LIMIT 2 3]
             assert_equal {d e f} [r zrangebyscore zset 0 10 LIMIT 2 10]
             assert_equal {}      [r zrangebyscore zset 0 10 LIMIT 20 10]
+            assert_equal {}      [r zrangebyscore zset 0 10 LIMIT -1 2]
             assert_equal {f e}   [r zrevrangebyscore zset 10 0 LIMIT 0 2]
             assert_equal {d c b} [r zrevrangebyscore zset 10 0 LIMIT 2 3]
             assert_equal {d c b} [r zrevrangebyscore zset 10 0 LIMIT 2 10]
             assert_equal {}      [r zrevrangebyscore zset 10 0 LIMIT 20 10]
+            assert_equal {}      [r zrevrangebyscore zset 10 0 LIMIT -1 2]
             # zrangebyscore uses different logic when offset > ZSKIPLIST_MAX_SEARCH
             create_long_zset zset 30
             assert_equal {i12 i13 i14} [r zrangebyscore zset 0 20 LIMIT 12 3]
             assert_equal {i14 i15}     [r zrangebyscore zset 0 20 LIMIT 14 2]
             assert_equal {i19 i20 i21} [r zrangebyscore zset 0 30 LIMIT 19 3]
-            assert_equal {i29}     [r zrangebyscore zset 10 30 LIMIT 19 2]
+            assert_equal {i29}         [r zrangebyscore zset 10 30 LIMIT 19 2]
+            assert_equal {}            [r zrangebyscore zset 0 20 LIMIT -1 3]
             assert_equal {i17 i16 i15} [r zrevrangebyscore zset 30 10 LIMIT 12 3]
             assert_equal {i6 i5}       [r zrevrangebyscore zset 20 0 LIMIT 14 2]
             assert_equal {i2 i1 i0}    [r zrevrangebyscore zset 20 0 LIMIT 18 5]
             assert_equal {i0}          [r zrevrangebyscore zset 20 0 LIMIT 20 5]
+            assert_equal {}            [r zrevrangebyscore zset 30 10 LIMIT -1 3]
         }
 
         test "ZRANGEBYSCORE with LIMIT and WITHSCORES - $encoding" {
@@ -680,9 +684,11 @@ start_server {tags {"zset"}} {
             assert_equal {bar} [r zrangebylex zset \[bar \[down LIMIT 0 1]
             assert_equal {cool} [r zrangebylex zset \[bar \[down LIMIT 1 1]
             assert_equal {bar cool down} [r zrangebylex zset \[bar \[down LIMIT 0 100]
+            assert_equal {} [r zrangebylex zset - \[cool LIMIT -1 2]
             assert_equal {omega hill great foo elephant} [r zrevrangebylex zset + \[d LIMIT 0 5]
             assert_equal {omega hill great foo} [r zrevrangebylex zset + \[d LIMIT 0 4]
             assert_equal {great foo elephant} [r zrevrangebylex zset + \[d LIMIT 2 3]
+            assert_equal {} [r zrevrangebylex zset + \[d LIMIT -1 5]
             # zrangebylex uses different logic when offset > ZSKIPLIST_MAX_SEARCH
             create_long_lex_zset
             assert_equal {max null} [r zrangebylex zset - \[tree LIMIT 12 2]
@@ -692,12 +698,14 @@ start_server {tags {"zset"}} {
             assert_equal {max} [r zrangebylex zset \[max \[null LIMIT 0 1]
             assert_equal {null} [r zrangebylex zset \[max \[null LIMIT 1 1]
             assert_equal {max null omega point} [r zrangebylex zset \[max \[point LIMIT 0 100]
+            assert_equal {} [r zrangebylex zset - \[tree LIMIT -1 2]
             assert_equal {tree sea result query point} [r zrevrangebylex zset + \[o LIMIT 0 5]
             assert_equal {tree sea result query} [r zrevrangebylex zset + \[o LIMIT 0 4]
             assert_equal {omega null max lip} [r zrevrangebylex zset + \[l LIMIT 5 4]
             assert_equal {elephant down} [r zrevrangebylex zset + \[a LIMIT 15 2]
             assert_equal {bar alpha} [r zrevrangebylex zset + - LIMIT 18 6]
             assert_equal {hill great foo} [r zrevrangebylex zset + \[c LIMIT 12 3]
+            assert_equal {} [r zrevrangebylex zset + \[o LIMIT -1 5]
         }
 
         test "ZRANGEBYLEX with invalid lex range specifiers - $encoding" {