fix(Textarea): count does not follow maxCharacter or maxLength (#4088)

* fix(Textarea): `count` does not follow `maxCharacter` or `maxLength`

* chore: stash changelog [ci skip]

---------

Co-authored-by: tdesign-bot <tdesign@tencent.com>

Author: RylanBot

packages/components/textarea/Textarea.tsx

@@ -209,7 +209,10 @@ const Textarea = forwardRef<TextareaRefInterface, TextareaProps>((originalProps,
     </div>
   );
 
-  const limitText = renderLimitText(currentLength, maxlength ?? maxcharacter);
+  const limitText = renderLimitText(
+    hasMaxcharacter ? characterLength : currentLength,
+    hasMaxcharacter ? maxcharacter : maxlength,
+  );
 
   return (
     <div style={style} ref={wrapperRef} className={classNames(`${classPrefix}-textarea`, className)}>

packages/components/textarea/__tests__/textarea.test.tsx

@@ -1,5 +1,5 @@
 import React from 'react';
-import { render, fireEvent, vi, mockDelay } from '@test/utils';
+import { fireEvent, mockDelay, render, vi } from '@test/utils';
 import { Textarea } from '..';
 
 describe('Textarea 组件测试', () => {
@@ -94,4 +94,24 @@ describe('Textarea 组件测试', () => {
 
     expect(container.getElementsByTagName('textarea')[0].selectionStart).toBe(value.length);
   });
+
+  test('count follows maxcharacter and maxlength correctly', async () => {
+    const LIMIT_SELECTOR = '.t-textarea__limit';
+
+    const { container: container1 } = render(<Textarea maxcharacter={15} value="hello世界" />);
+    const limitText1 = container1.querySelector(LIMIT_SELECTOR);
+    expect(limitText1?.textContent).toBe('9/15'); // hello(5) + 世(2) + 界(2) = 9
+
+    const { container: container2 } = render(<Textarea maxlength={15} value="hello世界" />);
+    const limitText2 = container2.querySelector(LIMIT_SELECTOR);
+    expect(limitText2?.textContent).toBe('7/15');
+
+    const { container: container3 } = render(<Textarea maxcharacter={15} value="hi👋🌍" />);
+    const limitText3 = container3.querySelector(LIMIT_SELECTOR);
+    expect(limitText3?.textContent).toBe('10/15'); // h(1) + i(1) + 👋(4) + 🌍(4) = 10
+
+    const { container: container4 } = render(<Textarea maxlength={15} value="hi👋🌍" />);
+    const limitText4 = container4.querySelector(LIMIT_SELECTOR);
+    expect(limitText4?.textContent).toBe('4/15');
+  });
 });

packages/tdesign-react/.changelog/pr-4088.md

@@ -0,0 +1,6 @@
+---
+pr_number: 4088
+contributor: RylanBot
+---
+
+- fix(Textarea): 修复 `count` 计算逻辑没有遵循 `maxcharacter` 或 `maxlength` 的问题 @RylanBot ([#4088](https://github.com/Tencent/tdesign-react/pull/4088))