fix(stream): use correct end_id in XPENDING command (#3276)

The XPENDING command was incorrectly using the start_id instead of the end_id
when parsing the range arguments. This caused incorrect filtering of pending
entries when a range was specified.

This commit fixes the issue by passing the correct end_id to the
ParseStreamEntryID function.

Author: i18nsite

tests/gocase/unit/type/stream/xpending_test.go

@@ -0,0 +1,56 @@
+package stream
+
+import (
+	"context"
+	"testing"
+
+	"github.com/apache/kvrocks/tests/gocase/util"
+	"github.com/redis/go-redis/v9"
+	"github.com/stretchr/testify/require"
+)
+
+func TestXPendingBug(t *testing.T) {
+	srv := util.StartServer(t, map[string]string{})
+	defer srv.Close()
+
+	ctx := context.Background()
+	rdb := srv.NewClient()
+	defer func() { require.NoError(t, rdb.Close()) }()
+
+	key := "stream_xpending_bug"
+	group := "group1"
+
+	// Create stream and group
+	require.NoError(t, rdb.XGroupCreateMkStream(ctx, key, group, "0").Err())
+
+	// Add messages
+	id1, err := rdb.XAdd(ctx, &redis.XAddArgs{Stream: key, Values: map[string]interface{}{"k": "v1"}}).Result()
+	require.NoError(t, err)
+	id2, err := rdb.XAdd(ctx, &redis.XAddArgs{Stream: key, Values: map[string]interface{}{"k": "v2"}}).Result()
+	require.NoError(t, err)
+
+	// Read to make them pending
+	_, err = rdb.XReadGroup(ctx, &redis.XReadGroupArgs{
+		Group:    group,
+		Consumer: "c1",
+		Streams:  []string{key, ">"},
+		Count:    10,
+	}).Result()
+	require.NoError(t, err)
+
+	// XPENDING key group - + 10
+	// If bug exists, this becomes XPENDING key group - - 10, which returns nothing (or only 0-0 if it existed)
+	res, err := rdb.XPendingExt(ctx, &redis.XPendingExtArgs{
+		Stream: key,
+		Group:  group,
+		Start:  "-",
+		End:    "+",
+		Count:  10,
+	}).Result()
+	require.NoError(t, err)
+
+	// Should have 2 pending items
+	require.Len(t, res, 2)
+	require.Equal(t, id1, res[0].ID)
+	require.Equal(t, id2, res[1].ID)
+}