feat: enhance handleRemove in Upload (#5974)

onRemove will be executed when removing file button is clicked, remove event will be prevented when return value is false.
But, if we want't to popup a confirm dialog, it can't block the execution of onRemove.
So, I add Promise support for onRemove. The return value of onRemove now can be a Promise, and the handleRemove function in Upload can wait for the non-blocking confirm dialog.

components/upload/Upload.tsx

@@ -167,18 +167,21 @@ export default class Upload extends React.Component<UploadProps, any> {
 
   handleRemove(file) {
     const { onRemove } = this.props;
-    // Prevent removing file
-    const onRemoveReturnValue = onRemove && onRemove(file);
-    if (onRemoveReturnValue === false) {
-      return;
-    }
-    const removedFileList = removeFileItem(file, this.state.fileList);
-    if (removedFileList) {
-      this.onChange({
-        file,
-        fileList: removedFileList,
-      });
-    }
+
+    Promise.resolve(typeof onRemove === 'function' ? onRemove(file) : onRemove).then(ret => {
+      // Prevent removing file
+      if (ret === false) {
+        return;
+      }
+
+      const removedFileList = removeFileItem(file, this.state.fileList);
+      if (removedFileList) {
+        this.onChange({
+          file,
+          fileList: removedFileList,
+        });
+      }
+    });
   }
 
   handleManualRemove = (file) => {

components/upload/index.en-US.md

@@ -34,7 +34,7 @@ Uploading is the process of publishing information (web pages, text, pictures, v
 | onChange   | A callback function, can be executed when uploading state is changing. See [onChange](#onChange)                | Function    | -   |
 | listType   | Built-in stylesheets, support for two types: `text` or `picture`     | string      | 'text'|
 | onPreview  | A callback function, will be executed when file link or preview icon is clicked.  | Function(file) | -  |
-| onRemove   | A callback function, will be executed when removing file button is clicked, remove event will be prevented when return value is `false` | Function(file): boolean | -   |
+| onRemove   | A callback function, will be executed when removing file button is clicked, remove event will be prevented when return value is `false` or a Promise which resolve(false) or reject. | Function(file): `boolean | Promise` | -   |
 | supportServerRender | Need to be turned on while the server side is rendering.| boolean | false    |
 | disabled | disable upload button | boolean | false    |
 | withCredentials | ajax upload with cookie sent | boolean | false |

components/upload/index.zh-CN.md

@@ -35,7 +35,7 @@ title: Upload
 | onChange   | 上传文件改变时的状态，详见 onChange                | Function    | 无    |
 | listType   | 上传列表的内建样式，支持两种基本样式 `text` or `picture`     | string      | 'text'|
 | onPreview  | 点击文件链接或预览图标时的回调                              | Function(file) | 无    |
-| onRemove   | 点击移除文件时的回调，返回值为 false 时不移除                | Function(file): Boolean | 无    |
+| onRemove   | 点击移除文件时的回调，返回值为 false 时不移除。支持返回一个 Promise 对象，Promise 对象 resolve(false) 或 reject 时不移除。                | Function(file): `boolean | Promise` | 无   |
 | supportServerRender | 服务端渲染时需要打开这个                           | boolean | false    |
 | disabled | 是否禁用                           | boolean | false    |
 | withCredentials | 上传请求时是否携带 cookie | boolean | false |