From 5ee5570ddd125777f0257b7f44050c908c0ded1f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E9=99=88=E5=AE=B6=E5=90=8D?= <chenjiaming@kezaihui.com>
Date: Wed, 1 Jul 2026 10:21:23 +0800
Subject: [PATCH] Fix truncation marker overflow

---
 common/src/util/__tests__/string.test.ts | 49 +++++++++++++++++++++++-
 common/src/util/string.ts                |  9 +++++
 2 files changed, 56 insertions(+), 2 deletions(-)

diff --git a/common/src/util/__tests__/string.test.ts b/common/src/util/__tests__/string.test.ts
index 3a141ca6b6..2c6bdb1187 100644
--- a/common/src/util/__tests__/string.test.ts
+++ b/common/src/util/__tests__/string.test.ts
@@ -1,6 +1,52 @@
 import { describe, expect, it } from 'bun:test'
 
-import { pluralize } from '../string'
+import { pluralize, truncateStringWithMessage } from '../string'
+
+describe('truncateStringWithMessage', () => {
+  it('should keep the truncation marker within maxLength for end truncation', () => {
+    const result = truncateStringWithMessage({
+      str: 'abcdefghijklmnopqrstuvwxyz',
+      maxLength: 10,
+    })
+
+    expect(result).toHaveLength(10)
+    expect(result).toBe('\n[TRUNCATE')
+  })
+
+  it('should keep the truncation marker within maxLength for start truncation', () => {
+    const result = truncateStringWithMessage({
+      str: 'abcdefghijklmnopqrstuvwxyz',
+      maxLength: 10,
+      remove: 'START',
+    })
+
+    expect(result).toHaveLength(10)
+    expect(result).toBe('[...TRUNCA')
+  })
+
+  it('should keep the truncation marker within maxLength for middle truncation', () => {
+    const result = truncateStringWithMessage({
+      str: 'abcdefghijklmnopqrstuvwxyz',
+      maxLength: 10,
+      remove: 'MIDDLE',
+    })
+
+    expect(result).toHaveLength(10)
+    expect(result).toBe('\n[...TRUNC')
+  })
+
+  it('should preserve context around the marker when maxLength allows it', () => {
+    const result = truncateStringWithMessage({
+      str: 'abcdefghijklmnopqrstuvwxyz',
+      maxLength: 19,
+      message: 'CUT',
+      remove: 'MIDDLE',
+    })
+
+    expect(result).toBe('abc\n[...CUT...]\nxyz')
+    expect(result).toHaveLength(19)
+  })
+})
 
 describe('pluralize', () => {
   it('should handle singular and plural cases correctly', () => {
@@ -236,4 +282,3 @@ describe('pluralize', () => {
     expect(pluralize(2, 'dependency')).toBe('2 dependencies')
   })
 })
-
diff --git a/common/src/util/string.ts b/common/src/util/string.ts
index 506de962fd..6f37310759 100644
--- a/common/src/util/string.ts
+++ b/common/src/util/string.ts
@@ -24,14 +24,23 @@ export const truncateStringWithMessage = ({
 
   if (remove === 'END') {
     const suffix = `\n[${message}...]`
+    if (suffix.length >= maxLength) {
+      return suffix.slice(0, maxLength)
+    }
     return str.slice(0, maxLength - suffix.length) + suffix
   }
   if (remove === 'START') {
     const prefix = `[...${message}]\n`
+    if (prefix.length >= maxLength) {
+      return prefix.slice(0, maxLength)
+    }
     return prefix + str.slice(str.length - maxLength + prefix.length)
   }
 
   const middle = `\n[...${message}...]\n`
+  if (middle.length >= maxLength) {
+    return middle.slice(0, maxLength)
+  }
   const length = Math.floor((maxLength - middle.length) / 2)
   return str.slice(0, length) + middle + str.slice(-length)
 }