puppeteer/src/common/JSHandle.ts
Dan Park a91b8aca37 feat: add drag-and-drop support (#7150)
This commit adds drag-and-drop support, leveraging new additions to the CDP Input domain (Input.setInterceptDrags, Input.dispatchDragEvent, and Input.dragIntercepted).
2021-06-07 13:50:34 +02:00

1064 lines
33 KiB
TypeScript

/**
* Copyright 2019 Google Inc. All rights reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
import { assert } from './assert.js';
import { helper, debugError } from './helper.js';
import { ExecutionContext } from './ExecutionContext.js';
import { Page } from './Page.js';
import { CDPSession } from './Connection.js';
import { KeyInput } from './USKeyboardLayout.js';
import { FrameManager, Frame } from './FrameManager.js';
import { getQueryHandlerAndSelector } from './QueryHandler.js';
import { Protocol } from 'devtools-protocol';
import {
EvaluateFn,
SerializableOrJSHandle,
EvaluateFnReturnType,
EvaluateHandleFn,
WrapElementHandle,
UnwrapPromiseLike,
} from './EvalTypes.js';
import { isNode } from '../environment.js';
/**
* @public
*/
export interface BoxModel {
content: Array<{ x: number; y: number }>;
padding: Array<{ x: number; y: number }>;
border: Array<{ x: number; y: number }>;
margin: Array<{ x: number; y: number }>;
width: number;
height: number;
}
/**
* @public
*/
export interface BoundingBox {
/**
* the x coordinate of the element in pixels.
*/
x: number;
/**
* the y coordinate of the element in pixels.
*/
y: number;
/**
* the width of the element in pixels.
*/
width: number;
/**
* the height of the element in pixels.
*/
height: number;
}
/**
* @internal
*/
export function createJSHandle(
context: ExecutionContext,
remoteObject: Protocol.Runtime.RemoteObject
): JSHandle {
const frame = context.frame();
if (remoteObject.subtype === 'node' && frame) {
const frameManager = frame._frameManager;
return new ElementHandle(
context,
context._client,
remoteObject,
frameManager.page(),
frameManager
);
}
return new JSHandle(context, context._client, remoteObject);
}
/**
* Represents an in-page JavaScript object. JSHandles can be created with the
* {@link Page.evaluateHandle | page.evaluateHandle} method.
*
* @example
* ```js
* const windowHandle = await page.evaluateHandle(() => window);
* ```
*
* JSHandle prevents the referenced JavaScript object from being garbage-collected
* unless the handle is {@link JSHandle.dispose | disposed}. JSHandles are auto-
* disposed when their origin frame gets navigated or the parent context gets destroyed.
*
* JSHandle instances can be used as arguments for {@link Page.$eval},
* {@link Page.evaluate}, and {@link Page.evaluateHandle}.
*
* @public
*/
export class JSHandle<HandleObjectType = unknown> {
/**
* @internal
*/
_context: ExecutionContext;
/**
* @internal
*/
_client: CDPSession;
/**
* @internal
*/
_remoteObject: Protocol.Runtime.RemoteObject;
/**
* @internal
*/
_disposed = false;
/**
* @internal
*/
constructor(
context: ExecutionContext,
client: CDPSession,
remoteObject: Protocol.Runtime.RemoteObject
) {
this._context = context;
this._client = client;
this._remoteObject = remoteObject;
}
/** Returns the execution context the handle belongs to.
*/
executionContext(): ExecutionContext {
return this._context;
}
/**
* This method passes this handle as the first argument to `pageFunction`.
* If `pageFunction` returns a Promise, then `handle.evaluate` would wait
* for the promise to resolve and return its value.
*
* @example
* ```js
* const tweetHandle = await page.$('.tweet .retweets');
* expect(await tweetHandle.evaluate(node => node.innerText)).toBe('10');
* ```
*/
async evaluate<T extends EvaluateFn<HandleObjectType>>(
pageFunction: T | string,
...args: SerializableOrJSHandle[]
): Promise<UnwrapPromiseLike<EvaluateFnReturnType<T>>> {
return await this.executionContext().evaluate<
UnwrapPromiseLike<EvaluateFnReturnType<T>>
>(pageFunction, this, ...args);
}
/**
* This method passes this handle as the first argument to `pageFunction`.
*
* @remarks
*
* The only difference between `jsHandle.evaluate` and
* `jsHandle.evaluateHandle` is that `jsHandle.evaluateHandle`
* returns an in-page object (JSHandle).
*
* If the function passed to `jsHandle.evaluateHandle` returns a Promise,
* then `evaluateHandle.evaluateHandle` waits for the promise to resolve and
* returns its value.
*
* See {@link Page.evaluateHandle} for more details.
*/
async evaluateHandle<HandleType extends JSHandle = JSHandle>(
pageFunction: EvaluateHandleFn,
...args: SerializableOrJSHandle[]
): Promise<HandleType> {
return await this.executionContext().evaluateHandle(
pageFunction,
this,
...args
);
}
/** Fetches a single property from the referenced object.
*/
async getProperty(propertyName: string): Promise<JSHandle | undefined> {
const objectHandle = await this.evaluateHandle(
(object: Element, propertyName: string) => {
const result = { __proto__: null };
result[propertyName] = object[propertyName];
return result;
},
propertyName
);
const properties = await objectHandle.getProperties();
const result = properties.get(propertyName) || null;
await objectHandle.dispose();
return result;
}
/**
* The method returns a map with property names as keys and JSHandle
* instances for the property values.
*
* @example
* ```js
* const listHandle = await page.evaluateHandle(() => document.body.children);
* const properties = await listHandle.getProperties();
* const children = [];
* for (const property of properties.values()) {
* const element = property.asElement();
* if (element)
* children.push(element);
* }
* children; // holds elementHandles to all children of document.body
* ```
*/
async getProperties(): Promise<Map<string, JSHandle>> {
const response = await this._client.send('Runtime.getProperties', {
objectId: this._remoteObject.objectId,
ownProperties: true,
});
const result = new Map<string, JSHandle>();
for (const property of response.result) {
if (!property.enumerable) continue;
result.set(property.name, createJSHandle(this._context, property.value));
}
return result;
}
/**
* @returns Returns a JSON representation of the object.If the object has a
* `toJSON` function, it will not be called.
* @remarks
*
* The JSON is generated by running {@link https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/JSON/stringify | JSON.stringify}
* on the object in page and consequent {@link https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/JSON/parse | JSON.parse} in puppeteer.
* **NOTE** The method throws if the referenced object is not stringifiable.
*/
async jsonValue<T = unknown>(): Promise<T> {
if (this._remoteObject.objectId) {
const response = await this._client.send('Runtime.callFunctionOn', {
functionDeclaration: 'function() { return this; }',
objectId: this._remoteObject.objectId,
returnByValue: true,
awaitPromise: true,
});
return helper.valueFromRemoteObject(response.result) as T;
}
return helper.valueFromRemoteObject(this._remoteObject) as T;
}
/**
* @returns Either `null` or the object handle itself, if the object
* handle is an instance of {@link ElementHandle}.
*/
asElement(): ElementHandle | null {
/* This always returns null, but subclasses can override this and return an
ElementHandle.
*/
return null;
}
/**
* Stops referencing the element handle, and resolves when the object handle is
* successfully disposed of.
*/
async dispose(): Promise<void> {
if (this._disposed) return;
this._disposed = true;
await helper.releaseObject(this._client, this._remoteObject);
}
/**
* Returns a string representation of the JSHandle.
*
* @remarks Useful during debugging.
*/
toString(): string {
if (this._remoteObject.objectId) {
const type = this._remoteObject.subtype || this._remoteObject.type;
return 'JSHandle@' + type;
}
return 'JSHandle:' + helper.valueFromRemoteObject(this._remoteObject);
}
}
/**
* ElementHandle represents an in-page DOM element.
*
* @remarks
*
* ElementHandles can be created with the {@link Page.$} method.
*
* ```js
* const puppeteer = require('puppeteer');
*
* (async () => {
* const browser = await puppeteer.launch();
* const page = await browser.newPage();
* await page.goto('https://example.com');
* const hrefElement = await page.$('a');
* await hrefElement.click();
* // ...
* })();
* ```
*
* ElementHandle prevents the DOM element from being garbage-collected unless the
* handle is {@link JSHandle.dispose | disposed}. ElementHandles are auto-disposed
* when their origin frame gets navigated.
*
* ElementHandle instances can be used as arguments in {@link Page.$eval} and
* {@link Page.evaluate} methods.
*
* If you're using TypeScript, ElementHandle takes a generic argument that
* denotes the type of element the handle is holding within. For example, if you
* have a handle to a `<select>` element, you can type it as
* `ElementHandle<HTMLSelectElement>` and you get some nicer type checks.
*
* @public
*/
export class ElementHandle<
ElementType extends Element = Element
> extends JSHandle<ElementType> {
private _page: Page;
private _frameManager: FrameManager;
/**
* @internal
*/
constructor(
context: ExecutionContext,
client: CDPSession,
remoteObject: Protocol.Runtime.RemoteObject,
page: Page,
frameManager: FrameManager
) {
super(context, client, remoteObject);
this._client = client;
this._remoteObject = remoteObject;
this._page = page;
this._frameManager = frameManager;
}
asElement(): ElementHandle<ElementType> | null {
return this;
}
/**
* Resolves to the content frame for element handles referencing
* iframe nodes, or null otherwise
*/
async contentFrame(): Promise<Frame | null> {
const nodeInfo = await this._client.send('DOM.describeNode', {
objectId: this._remoteObject.objectId,
});
if (typeof nodeInfo.node.frameId !== 'string') return null;
return this._frameManager.frame(nodeInfo.node.frameId);
}
private async _scrollIntoViewIfNeeded(): Promise<void> {
const error = await this.evaluate<
(
element: Element,
pageJavascriptEnabled: boolean
) => Promise<string | false>
>(async (element, pageJavascriptEnabled) => {
if (!element.isConnected) return 'Node is detached from document';
if (element.nodeType !== Node.ELEMENT_NODE)
return 'Node is not of type HTMLElement';
// force-scroll if page's javascript is disabled.
if (!pageJavascriptEnabled) {
element.scrollIntoView({
block: 'center',
inline: 'center',
// @ts-expect-error Chrome still supports behavior: instant but
// it's not in the spec so TS shouts We don't want to make this
// breaking change in Puppeteer yet so we'll ignore the line.
behavior: 'instant',
});
return false;
}
const visibleRatio = await new Promise((resolve) => {
const observer = new IntersectionObserver((entries) => {
resolve(entries[0].intersectionRatio);
observer.disconnect();
});
observer.observe(element);
});
if (visibleRatio !== 1.0) {
element.scrollIntoView({
block: 'center',
inline: 'center',
// @ts-expect-error Chrome still supports behavior: instant but
// it's not in the spec so TS shouts We don't want to make this
// breaking change in Puppeteer yet so we'll ignore the line.
behavior: 'instant',
});
}
return false;
}, this._page.isJavaScriptEnabled());
if (error) throw new Error(error);
}
async clickablePoint(): Promise<Point> {
const [result, layoutMetrics] = await Promise.all([
this._client
.send('DOM.getContentQuads', {
objectId: this._remoteObject.objectId,
})
.catch(debugError),
this._client.send('Page.getLayoutMetrics'),
]);
if (!result || !result.quads.length)
throw new Error('Node is either not visible or not an HTMLElement');
// Filter out quads that have too small area to click into.
const { clientWidth, clientHeight } = layoutMetrics.layoutViewport;
const quads = result.quads
.map((quad) => this._fromProtocolQuad(quad))
.map((quad) =>
this._intersectQuadWithViewport(quad, clientWidth, clientHeight)
)
.filter((quad) => computeQuadArea(quad) > 1);
if (!quads.length)
throw new Error('Node is either not visible or not an HTMLElement');
// Return the middle point of the first quad.
const quad = quads[0];
let x = 0;
let y = 0;
for (const point of quad) {
x += point.x;
y += point.y;
}
return {
x: x / 4,
y: y / 4,
};
}
private _getBoxModel(): Promise<void | Protocol.DOM.GetBoxModelResponse> {
const params: Protocol.DOM.GetBoxModelRequest = {
objectId: this._remoteObject.objectId,
};
return this._client
.send('DOM.getBoxModel', params)
.catch((error) => debugError(error));
}
private _fromProtocolQuad(quad: number[]): Array<{ x: number; y: number }> {
return [
{ x: quad[0], y: quad[1] },
{ x: quad[2], y: quad[3] },
{ x: quad[4], y: quad[5] },
{ x: quad[6], y: quad[7] },
];
}
private _intersectQuadWithViewport(
quad: Array<{ x: number; y: number }>,
width: number,
height: number
): Array<{ x: number; y: number }> {
return quad.map((point) => ({
x: Math.min(Math.max(point.x, 0), width),
y: Math.min(Math.max(point.y, 0), height),
}));
}
/**
* This method scrolls element into view if needed, and then
* uses {@link Page.mouse} to hover over the center of the element.
* If the element is detached from DOM, the method throws an error.
*/
async hover(): Promise<void> {
await this._scrollIntoViewIfNeeded();
const { x, y } = await this.clickablePoint();
await this._page.mouse.move(x, y);
}
/**
* This method scrolls element into view if needed, and then
* uses {@link Page.mouse} to click in the center of the element.
* If the element is detached from DOM, the method throws an error.
*/
async click(options: ClickOptions = {}): Promise<void> {
await this._scrollIntoViewIfNeeded();
const { x, y } = await this.clickablePoint();
await this._page.mouse.click(x, y, options);
}
/**
* This method creates and captures a dragevent from the element.
*/
async drag(target: Point): Promise<Protocol.Input.DragData> {
assert(
this._page.isDragInterceptionEnabled,
'Drag Interception is not enabled!'
);
await this._scrollIntoViewIfNeeded();
const start = await this.clickablePoint();
return await this._page.mouse.drag(start, target);
}
/**
* This method creates a `dragenter` event on the element.
*/
async dragEnter(
data: Protocol.Input.DragData = { items: [], dragOperationsMask: 1 }
): Promise<void> {
await this._scrollIntoViewIfNeeded();
const target = await this.clickablePoint();
await this._page.mouse.dragEnter(target, data);
}
/**
* This method creates a `dragover` event on the element.
*/
async dragOver(
data: Protocol.Input.DragData = { items: [], dragOperationsMask: 1 }
): Promise<void> {
await this._scrollIntoViewIfNeeded();
const target = await this.clickablePoint();
await this._page.mouse.dragOver(target, data);
}
/**
* This method triggers a drop on the element.
*/
async drop(
data: Protocol.Input.DragData = { items: [], dragOperationsMask: 1 }
): Promise<void> {
await this._scrollIntoViewIfNeeded();
const destination = await this.clickablePoint();
await this._page.mouse.drop(destination, data);
}
/**
* This method triggers a dragenter, dragover, and drop on the element.
*/
async dragAndDrop(
target: ElementHandle,
options?: { delay: number }
): Promise<void> {
await this._scrollIntoViewIfNeeded();
const startPoint = await this.clickablePoint();
const targetPoint = await target.clickablePoint();
await this._page.mouse.dragAndDrop(startPoint, targetPoint, options);
}
/**
* Triggers a `change` and `input` event once all the provided options have been
* selected. If there's no `<select>` element matching `selector`, the method
* throws an error.
*
* @example
* ```js
* handle.select('blue'); // single selection
* handle.select('red', 'green', 'blue'); // multiple selections
* ```
* @param values - Values of options to select. If the `<select>` has the
* `multiple` attribute, all values are considered, otherwise only the first
* one is taken into account.
*/
async select(...values: string[]): Promise<string[]> {
for (const value of values)
assert(
helper.isString(value),
'Values must be strings. Found value "' +
value +
'" of type "' +
typeof value +
'"'
);
return this.evaluate<(element: Element, values: string[]) => string[]>(
(element, values) => {
if (!(element instanceof HTMLSelectElement))
throw new Error('Element is not a <select> element.');
const options = Array.from(element.options);
element.value = undefined;
for (const option of options) {
option.selected = values.includes(option.value);
if (option.selected && !element.multiple) break;
}
element.dispatchEvent(new Event('input', { bubbles: true }));
element.dispatchEvent(new Event('change', { bubbles: true }));
return options
.filter((option) => option.selected)
.map((option) => option.value);
},
values
);
}
/**
* This method expects `elementHandle` to point to an
* {@link https://developer.mozilla.org/en-US/docs/Web/HTML/Element/input | input element}.
* @param filePaths - Sets the value of the file input to these paths.
* If some of the `filePaths` are relative paths, then they are resolved
* relative to the {@link https://nodejs.org/api/process.html#process_process_cwd | current working directory}
*/
async uploadFile(...filePaths: string[]): Promise<void> {
const isMultiple = await this.evaluate<(element: Element) => boolean>(
(element) => {
if (!(element instanceof HTMLInputElement)) {
throw new Error('uploadFile can only be called on an input element.');
}
return element.multiple;
}
);
assert(
filePaths.length <= 1 || isMultiple,
'Multiple file uploads only work with <input type=file multiple>'
);
if (!isNode) {
throw new Error(
`JSHandle#uploadFile can only be used in Node environments.`
);
}
/*
This import is only needed for `uploadFile`, so keep it scoped here to
avoid paying the cost unnecessarily.
*/
const path = await import('path');
const fs = await helper.importFSModule();
// Locate all files and confirm that they exist.
const files = await Promise.all(
filePaths.map(async (filePath) => {
const resolvedPath: string = path.resolve(filePath);
try {
await fs.promises.access(resolvedPath, fs.constants.R_OK);
} catch (error) {
if (error.code === 'ENOENT')
throw new Error(`${filePath} does not exist or is not readable`);
}
return resolvedPath;
})
);
const { objectId } = this._remoteObject;
const { node } = await this._client.send('DOM.describeNode', { objectId });
const { backendNodeId } = node;
/* The zero-length array is a special case, it seems that
DOM.setFileInputFiles does not actually update the files in that case,
so the solution is to eval the element value to a new FileList directly.
*/
if (files.length === 0) {
await (this as ElementHandle<HTMLInputElement>).evaluate((element) => {
element.files = new DataTransfer().files;
// Dispatch events for this case because it should behave akin to a user action.
element.dispatchEvent(new Event('input', { bubbles: true }));
element.dispatchEvent(new Event('change', { bubbles: true }));
});
} else {
await this._client.send('DOM.setFileInputFiles', {
objectId,
files,
backendNodeId,
});
}
}
/**
* This method scrolls element into view if needed, and then uses
* {@link Touchscreen.tap} to tap in the center of the element.
* If the element is detached from DOM, the method throws an error.
*/
async tap(): Promise<void> {
await this._scrollIntoViewIfNeeded();
const { x, y } = await this.clickablePoint();
await this._page.touchscreen.tap(x, y);
}
/**
* Calls {@link https://developer.mozilla.org/en-US/docs/Web/API/HTMLElement/focus | focus} on the element.
*/
async focus(): Promise<void> {
await (this as ElementHandle<HTMLElement>).evaluate((element) =>
element.focus()
);
}
/**
* Focuses the element, and then sends a `keydown`, `keypress`/`input`, and
* `keyup` event for each character in the text.
*
* To press a special key, like `Control` or `ArrowDown`,
* use {@link ElementHandle.press}.
*
* @example
* ```js
* await elementHandle.type('Hello'); // Types instantly
* await elementHandle.type('World', {delay: 100}); // Types slower, like a user
* ```
*
* @example
* An example of typing into a text field and then submitting the form:
*
* ```js
* const elementHandle = await page.$('input');
* await elementHandle.type('some text');
* await elementHandle.press('Enter');
* ```
*/
async type(text: string, options?: { delay: number }): Promise<void> {
await this.focus();
await this._page.keyboard.type(text, options);
}
/**
* Focuses the element, and then uses {@link Keyboard.down} and {@link Keyboard.up}.
*
* @remarks
* If `key` is a single character and no modifier keys besides `Shift`
* are being held down, a `keypress`/`input` event will also be generated.
* The `text` option can be specified to force an input event to be generated.
*
* **NOTE** Modifier keys DO affect `elementHandle.press`. Holding down `Shift`
* will type the text in upper case.
*
* @param key - Name of key to press, such as `ArrowLeft`.
* See {@link KeyInput} for a list of all key names.
*/
async press(key: KeyInput, options?: PressOptions): Promise<void> {
await this.focus();
await this._page.keyboard.press(key, options);
}
/**
* This method returns the bounding box of the element (relative to the main frame),
* or `null` if the element is not visible.
*/
async boundingBox(): Promise<BoundingBox | null> {
const result = await this._getBoxModel();
if (!result) return null;
const quad = result.model.border;
const x = Math.min(quad[0], quad[2], quad[4], quad[6]);
const y = Math.min(quad[1], quad[3], quad[5], quad[7]);
const width = Math.max(quad[0], quad[2], quad[4], quad[6]) - x;
const height = Math.max(quad[1], quad[3], quad[5], quad[7]) - y;
return { x, y, width, height };
}
/**
* This method returns boxes of the element, or `null` if the element is not visible.
*
* @remarks
*
* Boxes are represented as an array of points;
* Each Point is an object `{x, y}`. Box points are sorted clock-wise.
*/
async boxModel(): Promise<BoxModel | null> {
const result = await this._getBoxModel();
if (!result) return null;
const { content, padding, border, margin, width, height } = result.model;
return {
content: this._fromProtocolQuad(content),
padding: this._fromProtocolQuad(padding),
border: this._fromProtocolQuad(border),
margin: this._fromProtocolQuad(margin),
width,
height,
};
}
/**
* This method scrolls element into view if needed, and then uses
* {@link Page.screenshot} to take a screenshot of the element.
* If the element is detached from DOM, the method throws an error.
*/
async screenshot(options = {}): Promise<string | Buffer | void> {
let needsViewportReset = false;
let boundingBox = await this.boundingBox();
assert(boundingBox, 'Node is either not visible or not an HTMLElement');
const viewport = this._page.viewport();
if (
viewport &&
(boundingBox.width > viewport.width ||
boundingBox.height > viewport.height)
) {
const newViewport = {
width: Math.max(viewport.width, Math.ceil(boundingBox.width)),
height: Math.max(viewport.height, Math.ceil(boundingBox.height)),
};
await this._page.setViewport(Object.assign({}, viewport, newViewport));
needsViewportReset = true;
}
await this._scrollIntoViewIfNeeded();
boundingBox = await this.boundingBox();
assert(boundingBox, 'Node is either not visible or not an HTMLElement');
assert(boundingBox.width !== 0, 'Node has 0 width.');
assert(boundingBox.height !== 0, 'Node has 0 height.');
const {
layoutViewport: { pageX, pageY },
} = await this._client.send('Page.getLayoutMetrics');
const clip = Object.assign({}, boundingBox);
clip.x += pageX;
clip.y += pageY;
const imageData = await this._page.screenshot(
Object.assign(
{},
{
clip,
},
options
)
);
if (needsViewportReset) await this._page.setViewport(viewport);
return imageData;
}
/**
* Runs `element.querySelector` within the page. If no element matches the selector,
* the return value resolves to `null`.
*/
async $<T extends Element = Element>(
selector: string
): Promise<ElementHandle<T> | null> {
const { updatedSelector, queryHandler } =
getQueryHandlerAndSelector(selector);
return queryHandler.queryOne(this, updatedSelector);
}
/**
* Runs `element.querySelectorAll` within the page. If no elements match the selector,
* the return value resolves to `[]`.
*/
async $$<T extends Element = Element>(
selector: string
): Promise<Array<ElementHandle<T>>> {
const { updatedSelector, queryHandler } =
getQueryHandlerAndSelector(selector);
return queryHandler.queryAll(this, updatedSelector);
}
/**
* This method runs `document.querySelector` within the element and passes it as
* the first argument to `pageFunction`. If there's no element matching `selector`,
* the method throws an error.
*
* If `pageFunction` returns a Promise, then `frame.$eval` would wait for the promise
* to resolve and return its value.
*
* @example
* ```js
* const tweetHandle = await page.$('.tweet');
* expect(await tweetHandle.$eval('.like', node => node.innerText)).toBe('100');
* expect(await tweetHandle.$eval('.retweets', node => node.innerText)).toBe('10');
* ```
*/
async $eval<ReturnType>(
selector: string,
pageFunction: (
element: Element,
...args: unknown[]
) => ReturnType | Promise<ReturnType>,
...args: SerializableOrJSHandle[]
): Promise<WrapElementHandle<ReturnType>> {
const elementHandle = await this.$(selector);
if (!elementHandle)
throw new Error(
`Error: failed to find element matching selector "${selector}"`
);
const result = await elementHandle.evaluate<
(
element: Element,
...args: SerializableOrJSHandle[]
) => ReturnType | Promise<ReturnType>
>(pageFunction, ...args);
await elementHandle.dispose();
/**
* This `as` is a little unfortunate but helps TS understand the behavior of
* `elementHandle.evaluate`. If evaluate returns an element it will return an
* ElementHandle instance, rather than the plain object. All the
* WrapElementHandle type does is wrap ReturnType into
* ElementHandle<ReturnType> if it is an ElementHandle, or leave it alone as
* ReturnType if it isn't.
*/
return result as WrapElementHandle<ReturnType>;
}
/**
* This method runs `document.querySelectorAll` within the element and passes it as
* the first argument to `pageFunction`. If there's no element matching `selector`,
* the method throws an error.
*
* If `pageFunction` returns a Promise, then `frame.$$eval` would wait for the
* promise to resolve and return its value.
*
* @example
* ```html
* <div class="feed">
* <div class="tweet">Hello!</div>
* <div class="tweet">Hi!</div>
* </div>
* ```
*
* @example
* ```js
* const feedHandle = await page.$('.feed');
* expect(await feedHandle.$$eval('.tweet', nodes => nodes.map(n => n.innerText)))
* .toEqual(['Hello!', 'Hi!']);
* ```
*/
async $$eval<ReturnType>(
selector: string,
pageFunction: (
elements: Element[],
...args: unknown[]
) => ReturnType | Promise<ReturnType>,
...args: SerializableOrJSHandle[]
): Promise<WrapElementHandle<ReturnType>> {
const { updatedSelector, queryHandler } =
getQueryHandlerAndSelector(selector);
const arrayHandle = await queryHandler.queryAllArray(this, updatedSelector);
const result = await arrayHandle.evaluate<
(
elements: Element[],
...args: unknown[]
) => ReturnType | Promise<ReturnType>
>(pageFunction, ...args);
await arrayHandle.dispose();
/* This `as` exists for the same reason as the `as` in $eval above.
* See the comment there for a full explanation.
*/
return result as WrapElementHandle<ReturnType>;
}
/**
* The method evaluates the XPath expression relative to the elementHandle.
* If there are no such elements, the method will resolve to an empty array.
* @param expression - Expression to {@link https://developer.mozilla.org/en-US/docs/Web/API/Document/evaluate | evaluate}
*/
async $x(expression: string): Promise<ElementHandle[]> {
const arrayHandle = await this.evaluateHandle(
(element: Document, expression: string) => {
const document = element.ownerDocument || element;
const iterator = document.evaluate(
expression,
element,
null,
XPathResult.ORDERED_NODE_ITERATOR_TYPE
);
const array = [];
let item;
while ((item = iterator.iterateNext())) array.push(item);
return array;
},
expression
);
const properties = await arrayHandle.getProperties();
await arrayHandle.dispose();
const result = [];
for (const property of properties.values()) {
const elementHandle = property.asElement();
if (elementHandle) result.push(elementHandle);
}
return result;
}
/**
* Resolves to true if the element is visible in the current viewport.
*/
async isIntersectingViewport(): Promise<boolean> {
return await this.evaluate<(element: Element) => Promise<boolean>>(
async (element) => {
const visibleRatio = await new Promise((resolve) => {
const observer = new IntersectionObserver((entries) => {
resolve(entries[0].intersectionRatio);
observer.disconnect();
});
observer.observe(element);
});
return visibleRatio > 0;
}
);
}
}
/**
* @public
*/
export interface ClickOptions {
/**
* Time to wait between `mousedown` and `mouseup` in milliseconds.
*
* @defaultValue 0
*/
delay?: number;
/**
* @defaultValue 'left'
*/
button?: 'left' | 'right' | 'middle';
/**
* @defaultValue 1
*/
clickCount?: number;
}
/**
* @public
*/
export interface PressOptions {
/**
* Time to wait between `keydown` and `keyup` in milliseconds. Defaults to 0.
*/
delay?: number;
/**
* If specified, generates an input event with this text.
*/
text?: string;
}
/**
* @public
*/
export interface Point {
x: number;
y: number;
}
function computeQuadArea(quad: Array<{ x: number; y: number }>): number {
/* Compute sum of all directed areas of adjacent triangles
https://en.wikipedia.org/wiki/Polygon#Simple_polygons
*/
let area = 0;
for (let i = 0; i < quad.length; ++i) {
const p1 = quad[i];
const p2 = quad[(i + 1) % quad.length];
area += (p1.x * p2.y - p2.x * p1.y) / 2;
}
return Math.abs(area);
}