Add drag-and-drop support.

docs/api.md

@@ -155,6 +155,7 @@
   * [page.goto(url[, options])](#pagegotourl-options)
   * [page.hover(selector)](#pagehoverselector)
   * [page.isClosed()](#pageisclosed)
+  * [page.isDragInterceptionEnabled](#pageisdraginterceptionenabled)
   * [page.isJavaScriptEnabled()](#pageisjavascriptenabled)
   * [page.keyboard](#pagekeyboard)
   * [page.mainFrame()](#pagemainframe)
@@ -171,6 +172,7 @@
   * [page.setCookie(...cookies)](#pagesetcookiecookies)
   * [page.setDefaultNavigationTimeout(timeout)](#pagesetdefaultnavigationtimeouttimeout)
   * [page.setDefaultTimeout(timeout)](#pagesetdefaulttimeouttimeout)
+  * [page.setDragInterception(enabled)](#pagesetdraginterceptionenabled)
   * [page.setExtraHTTPHeaders(headers)](#pagesetextrahttpheadersheaders)
   * [page.setGeolocation(options)](#pagesetgeolocationoptions)
   * [page.setJavaScriptEnabled(enabled)](#pagesetjavascriptenabledenabled)
@@ -214,6 +216,11 @@
 - [class: Mouse](#class-mouse)
   * [mouse.click(x, y[, options])](#mouseclickx-y-options)
   * [mouse.down([options])](#mousedownoptions)
+  * [mouse.drag(start, target)](#mousedragstart-target)
+  * [mouse.dragAndDrop(start, target[, options])](#mousedraganddropstart-target-options)
+  * [mouse.dragEnter(target, data)](#mousedragentertarget-data)
+  * [mouse.dragOver(target, data)](#mousedragovertarget-data)
+  * [mouse.drop(target, data)](#mousedroptarget-data)
   * [mouse.move(x, y[, options])](#mousemovex-y-options)
   * [mouse.up([options])](#mouseupoptions)
   * [mouse.wheel([options])](#mousewheeloptions)
@@ -294,8 +301,14 @@
   * [elementHandle.boundingBox()](#elementhandleboundingbox)
   * [elementHandle.boxModel()](#elementhandleboxmodel)
   * [elementHandle.click([options])](#elementhandleclickoptions)
+  * [elementHandle.clickablePoint()](#elementhandleclickablepoint)
   * [elementHandle.contentFrame()](#elementhandlecontentframe)
   * [elementHandle.dispose()](#elementhandledispose)
+  * [elementHandle.drag(target)](#elementhandledragtarget)
+  * [elementHandle.dragAndDrop(target[, options])](#elementhandledraganddroptarget-options)
+  * [elementHandle.dragEnter([data])](#elementhandledragenterdata)
+  * [elementHandle.dragOver([data])](#elementhandledragoverdata)
+  * [elementHandle.drop([data])](#elementhandledropdata)
   * [elementHandle.evaluate(pageFunction[, ...args])](#elementhandleevaluatepagefunction-args)
   * [elementHandle.evaluateHandle(pageFunction[, ...args])](#elementhandleevaluatehandlepagefunction-args)
   * [elementHandle.executionContext()](#elementhandleexecutioncontext)
@@ -1919,6 +1932,12 @@ Shortcut for [page.mainFrame().hover(selector)](#framehoverselector).
 
 Indicates that the page has been closed.
 
+#### page.isDragInterceptionEnabled
+
+- returns: <[boolean]>
+
+Indicates that drag events are being intercepted.
+
 #### page.isJavaScriptEnabled()
 
 - returns: <[boolean]>
@@ -2183,6 +2202,13 @@ This setting will change the default maximum time for the following methods and
 
 > **NOTE** [`page.setDefaultNavigationTimeout`](#pagesetdefaultnavigationtimeouttimeout) takes priority over [`page.setDefaultTimeout`](#pagesetdefaulttimeouttimeout)
 
+#### page.setDragInterception(enabled)
+
+- `enabled` <[boolean]>
+- returns: <[Promise]>
+
+Enables the Input.drag methods. This provides the capability to cpature drag events emitted on the page, which can then be used to simulate drag-and-drop.
+
 #### page.setExtraHTTPHeaders(headers)
 
 - `headers` <[Object]> An object containing additional HTTP headers to be sent with every request. All header values must be strings.
@@ -2960,6 +2986,62 @@ Shortcut for [`mouse.move`](#mousemovex-y-options), [`mouse.down`](#mousedownopt
 
 Dispatches a `mousedown` event.
 
+#### mouse.drag(start, target)
+
+- `start` <[Object]> the position to start dragging from
+  - `x` <[number]> x coordinate
+  - `y` <[number]> y coordinate
+- `target` <[Object]> the position to drag to
+  - `x` <[number]> x coordinate
+  - `y` <[number]> y coordinate
+- returns: <[Promise<[DragData]>]>
+
+This method creates and captures a dragevent from a given point.
+
+#### mouse.dragAndDrop(start, target[, options])
+
+- `start` <[Object]>
+  - `x` <[number]> x coordinate
+  - `y` <[number]> y coordinate
+- `target` <[Object]>
+  - `x` <[number]> x coordinate
+  - `y` <[number]> y coordinate
+- `options` <[Object]>
+  - `delay` <[number]> how long to delay before dropping onto the target point
+- returns: <[Promise<[DragData]>]>
+
+This method drags from a given start point and drops onto a target point.
+
+#### mouse.dragEnter(target, data)
+
+- `target` <[Object]>
+  - `x` <[number]> x coordinate
+  - `y` <[number]> y coordinate
+- `data` <[Object]>
+- returns: <[Promise]]>
+
+This method triggers a dragenter event from the target point.
+
+#### mouse.dragOver(target, data)
+
+- `target` <[Object]>
+  - `x` <[number]> x coordinate
+  - `y` <[number]> y coordinate
+- `data` <[Object]>
+- returns: <[Promise]]>
+
+This method triggers a dragover event from the target point.
+
+#### mouse.drop(target, data)
+
+- `target` <[Object]>
+  - `x` <[number]> x coordinate
+  - `y` <[number]> y coordinate
+- `data` <[Object]>
+- returns: <[Promise]]>
+
+This method triggers a drop event from the target point.
+
 #### mouse.move(x, y[, options])
 
 - `x` <[number]>
@@ -4035,6 +4117,10 @@ This method returns boxes of the element, or `null` if the element is not visibl
 This method scrolls element into view if needed, and then uses [page.mouse](#pagemouse) to click in the center of the element.
 If the element is detached from DOM, the method throws an error.
 
+#### elementHandle.clickablePoint()
+
+- returns: <[Promise<[Point]>]> Resolves to the x, y point that describes the element's position.
+
 #### elementHandle.contentFrame()
 
 - returns: <[Promise]<?[Frame]>> Resolves to the content frame for element handles referencing iframe nodes, or null otherwise
@@ -4045,6 +4131,45 @@ If the element is detached from DOM, the method throws an error.
 
 The `elementHandle.dispose` method stops referencing the element handle.
 
+#### elementHandle.drag(target)
+
+- `target` <[Object]>
+  - `x` <[number]> x coordinate
+  - `y` <[number]> y coordinate
+- returns: <[Promise<[DragData]>]>
+
+This method creates and captures a drag event from the element.
+
+#### elementHandle.dragAndDrop(target[, options])
+
+- `target` <[ElementHandle]>
+- `options` <[Object]>
+  - `delay` <[number]> how long to delay before dropping onto the target element
+- returns: <[Promise]>
+
+This method will drag a given element and drop it onto a target element.
+
+#### elementHandle.dragEnter([data])
+
+- `data` <[Object]> drag data created from `element.drag`
+- returns: <[Promise]>
+
+This method will trigger a dragenter event from the given element.
+
+#### elementHandle.dragOver([data])
+
+- `data` <[Object]> drag data created from `element.drag`
+- returns: <[Promise]>
+
+This method will trigger a dragover event from the given element.
+
+#### elementHandle.drop([data])
+
+- `data` <[Object]> drag data created from `element.drag`
+- returns: <[Promise]>
+
+This method will trigger a drop event from the given element.
+
 #### elementHandle.evaluate(pageFunction[, ...args])
 
 - `pageFunction` <[function]\([Object]\)> Function to be evaluated in browser context

src/common/Input.ts

@@ -17,6 +17,8 @@
 import { assert } from './assert.js';
 import { CDPSession } from './Connection.js';
 import { keyDefinitions, KeyDefinition, KeyInput } from './USKeyboardLayout.js';
+import { Protocol } from 'devtools-protocol';
+import { Point } from './JSHandle.js';
 
 type KeyDescription = Required<
   Pick<KeyDefinition, 'keyCode' | 'key' | 'text' | 'code' | 'location'>
@@ -485,6 +487,98 @@ export class Mouse {
       pointerType: 'mouse',
     });
   }
+
+  /**
+   * Dispatches a `drag` event.
+   * @param start - starting point for drag
+   * @param target - point to drag to
+   * ```
+   */
+  async drag(start: Point, target: Point): Promise<Protocol.Input.DragData> {
+    const promise = new Promise<Protocol.Input.DragData>((resolve) => {
+      this._client.once('Input.dragIntercepted', (event) =>
+        resolve(event.data)
+      );
+    });
+    await this.move(start.x, start.y);
+    await this.down();
+    await this.move(target.x, target.y);
+    return promise;
+  }
+
+  /**
+   * Dispatches a `dragenter` event.
+   * @param target - point for emitting `dragenter` event
+   * ```
+   */
+  async dragEnter(target: Point, data: Protocol.Input.DragData): Promise<void> {
+    await this._client.send('Input.dispatchDragEvent', {
+      type: 'dragEnter',
+      x: target.x,
+      y: target.y,
+      modifiers: this._keyboard._modifiers,
+      data,
+    });
+  }
+
+  /**
+   * Dispatches a `dragover` event.
+   * @param target - point for emitting `dragover` event
+   * ```
+   */
+  async dragOver(target: Point, data: Protocol.Input.DragData): Promise<void> {
+    await this._client.send('Input.dispatchDragEvent', {
+      type: 'dragOver',
+      x: target.x,
+      y: target.y,
+      modifiers: this._keyboard._modifiers,
+      data,
+    });
+  }
+
+  /**
+   * Performs a dragenter, dragover, and drop in sequence.
+   * @param target - point to drop on
+   * @param data - drag data containing items and operations mask
+   * @param options - An object of options. Accepts delay which,
+   * if specified, is the time to wait between `dragover` and `drop` in milliseconds.
+   * Defaults to 0.
+   * ```
+   */
+  async drop(target: Point, data: Protocol.Input.DragData): Promise<void> {
+    await this._client.send('Input.dispatchDragEvent', {
+      type: 'drop',
+      x: target.x,
+      y: target.y,
+      modifiers: this._keyboard._modifiers,
+      data,
+    });
+  }
+
+  /**
+   * Performs a drag, dragenter, dragover, and drop in sequence.
+   * @param target - point to drag from
+   * @param target - point to drop on
+   * @param options - An object of options. Accepts delay which,
+   * if specified, is the time to wait between `dragover` and `drop` in milliseconds.
+   * Defaults to 0.
+   * ```
+   */
+  async dragAndDrop(
+    start: Point,
+    target: Point,
+    options: { delay?: number } = {}
+  ): Promise<void> {
+    const { delay = null } = options;
+    const data = await this.drag(start, target);
+    await this.dragEnter(target, data);
+    await this.dragOver(target, data);
+    if (delay) {
+      await new Promise((resolve) => setTimeout(resolve, delay));
+    }
+    await this.drop(target, data);
+    await this.up();
+  }
 }
 
 /**