From 6fca53f6ec390a29a11fc2f979cdfc8cf3a47ffd Mon Sep 17 00:00:00 2001
From: Zihan Dai <dzh1436286758@gmail.com>
Date: Tue, 10 Nov 2026 20:24:27 +1100
Subject: [PATCH] fix(search): stop user:me matching other usernames

parseUserID checked strings.Contains(q, "user:me"), so a search for
"user:melissa" (or any username that starts with "me") was treated as
"user:me": it filtered by the searcher's own ID, or by no one for a
visitor, and left "lissa" behind as a search word.

Treat the query as "user:me" only when the username in the user: token
is exactly "me".
---
 .../service/search_parser/search_parser.go    |  7 +-
 .../search_parser/search_parser_test.go       | 71 +++++++++++++++++++
 2 files changed, 75 insertions(+), 3 deletions(-)
 create mode 100644 internal/service/search_parser/search_parser_test.go

diff --git a/internal/service/search_parser/search_parser.go b/internal/service/search_parser/search_parser.go
index 3e6182e15..20bbcf949 100644
--- a/internal/service/search_parser/search_parser.go
+++ b/internal/service/search_parser/search_parser.go
@@ -155,15 +155,16 @@ func (sp *SearchParser) parseTags(ctx context.Context, query *string) (tags [][]
 func (sp *SearchParser) parseUserID(ctx context.Context, query *string, currentUserID string) (userID string) {
 	var (
 		exprUsername = `user:(\S+)`
-		exprMe       = "user:me"
+		me           = "me"
 		q            = *query
 	)
 
 	re := regexp.MustCompile(exprUsername)
 	res := re.FindStringSubmatch(q)
-	if strings.Contains(q, exprMe) {
+	// only "user:me" itself means the current user, not a username that starts with "me"
+	if len(res) > 1 && res[1] == me {
 		userID = currentUserID
-		q = strings.ReplaceAll(q, exprMe, "")
+		q = re.ReplaceAllString(q, "")
 	} else if len(res) > 1 {
 		name := res[1]
 		user, has, err := sp.userCommon.GetUserBasicInfoByUserName(ctx, name)
diff --git a/internal/service/search_parser/search_parser_test.go b/internal/service/search_parser/search_parser_test.go
new file mode 100644
index 000000000..5421591e8
--- /dev/null
+++ b/internal/service/search_parser/search_parser_test.go
@@ -0,0 +1,71 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+package search_parser
+
+import (
+	"context"
+	"testing"
+
+	"github.com/apache/answer/internal/entity"
+	"github.com/apache/answer/internal/schema"
+	"github.com/apache/answer/internal/service/mock"
+	usercommon "github.com/apache/answer/internal/service/user_common"
+	"github.com/stretchr/testify/assert"
+	"go.uber.org/mock/gomock"
+)
+
+type usernameRepo struct {
+	usercommon.UserRepo
+	users map[string]*entity.User
+}
+
+func (r *usernameRepo) GetByUsername(_ context.Context, username string) (*entity.User, bool, error) {
+	user, ok := r.users[username]
+	return user, ok, nil
+}
+
+func TestParseStructureUser(t *testing.T) {
+	ctrl := gomock.NewController(t)
+	siteInfo := mock.NewMockSiteInfoCommonService(ctrl)
+	siteInfo.EXPECT().FormatAvatar(gomock.Any(), gomock.Any(), gomock.Any(), gomock.Any()).
+		Return(&schema.AvatarInfo{}).AnyTimes()
+	repo := &usernameRepo{users: map[string]*entity.User{
+		"melissa": {ID: "2", Username: "melissa"},
+	}}
+	sp := NewSearchParser(nil, usercommon.NewUserCommon(repo, nil, nil, siteInfo))
+
+	tests := []struct {
+		query     string
+		wantUser  string
+		wantWords []string
+	}{
+		{query: "user:me", wantUser: "1"},
+		{query: "user:me service", wantUser: "1", wantWords: []string{"service"}},
+		{query: "user:melissa", wantUser: "2"},
+		{query: "user:melissa service", wantUser: "2", wantWords: []string{"service"}},
+	}
+	for _, tt := range tests {
+		t.Run(tt.query, func(t *testing.T) {
+			cond := sp.ParseStructure(context.Background(), &schema.SearchDTO{Query: tt.query, UserID: "1"})
+			assert.Equal(t, tt.wantUser, cond.UserID)
+			assert.ElementsMatch(t, tt.wantWords, cond.Words)
+		})
+	}
+}