Repository: ant-design/ant-design-mobile (ts)

Issue:
TextArea的最外层容器.adm-text-area未加position: relative;会导致auoSize异常。
### Version of antd-mobile

5.31.1

### Operating system and its version

iOS, Android

### Browser and its version

_No response_

### Sandbox to reproduce

_No response_

### What happened?

如题，你们简单修复下吧，我就不蹭PR了

### Relevant log output

_No response_

Pull request description:
fix(TextArea): hidden textarea element is not positioned relative to its parent
fix #6238
这个 absolute 没比较的父级定位，换行计算错误了

![image](https://github.com/ant-design/ant-design-mobile/assets/77056991/2a7d2449-8240-41e3-aeb4-19a50848858c)


Patch:
diff --git a/src/components/text-area/text-area.less b/src/components/text-area/text-area.less
index c2c10679f..048f80f54 100644
--- a/src/components/text-area/text-area.less
+++ b/src/components/text-area/text-area.less
@@ -5,7 +5,7 @@
   --disabled-color: var(--adm-color-weak);
   --text-align: left;
   --count-text-align: right;
-
+  position: relative;
   width: 100%;
   max-width: 100%;
   max-height: 100%;
diff --git a/src/components/virtual-input/virtual-input.tsx b/src/components/virtual-input/virtual-input.tsx
index 6e764320b..11751f9fc 100644
--- a/src/components/virtual-input/virtual-input.tsx
+++ b/src/components/virtual-input/virtual-input.tsx
@@ -151,7 +151,7 @@ export const VirtualInput = forwardRef<VirtualInputRef, VirtualInputProps>(
             <CloseCircleFill />
           </div>
         )}
-        {!value && (
+        {[undefined, null, ''].includes(value) && (
           <div className={`${classPrefix}-placeholder`}>
             {props.placeholder}
           </div>


Test patch:
diff --git a/src/components/virtual-input/tests/virtual-input.test.tsx b/src/components/virtual-input/tests/virtual-input.test.tsx
index 5e12b3567..0cd11daab 100644
--- a/src/components/virtual-input/tests/virtual-input.test.tsx
+++ b/src/components/virtual-input/tests/virtual-input.test.tsx
@@ -108,4 +108,9 @@ describe('VirtualInput', () => {
       ).not.toBeVisible()
     })
   })
+
+  test('placeholder should not be shown when value is `0`', () => {
+    render(<VirtualInput value={0 as any} placeholder='placeholder' />)
+    expect(screen.queryByText('placeholder')).toBeNull()
+  })
 })