/**
* @license
* Copyright 2018 Google Inc.
* SPDX-License-Identifier: Apache-2.0
*/
import assert from 'assert' ;
import expect from 'expect' ;
import {
getTestState,
setupSeparateTestBrowserHooks,
setupTestBrowserHooks,
} from './mocha-utils.js' ;
describe('Screenshots' , function () {
setupTestBrowserHooks();
const state = setupSeparateTestBrowserHooks({
defaultViewport: null ,
});
describe('Page.screenshot' , function () {
it('should work' , async () => {
const {page, server} = await getTestState();
await page.setViewport({width: 500 , height: 500 });
await page.goto (server.PREFIX + '/grid.html' );
const screenshot = await page.screenshot();
expect(screenshot).toBeGolden('screenshot-sanity.png' );
});
it('should clip rect' , async () => {
const {page, server} = await getTestState();
await page.setViewport({width: 500 , height: 500 });
await page.goto (server.PREFIX + '/grid.html' );
const screenshot = await page.screenshot({
clip: {
x: 50 ,
y: 100 ,
width: 150 ,
height: 100 ,
},
});
expect(screenshot).toBeGolden('screenshot-clip-rect.png' );
});
it('should get screenshot bigger than the viewport' , async () => {
const {page, server} = await getTestState();
await page.setViewport({width: 50 , height: 50 });
await page.goto (server.PREFIX + '/grid.html' );
const screenshot = await page.screenshot({
clip: {
x: 25 ,
y: 25 ,
width: 100 ,
height: 100 ,
},
});
expect(screenshot).toBeGolden('screenshot-offscreen-clip.png' );
});
it('should clip clip bigger than the viewport without "captureBeyondViewport"' , async () => {
const {page, server} = await getTestState();
await page.setViewport({width: 50 , height: 50 });
await page.goto (server.PREFIX + '/grid.html' );
const screenshot = await page.screenshot({
captureBeyondViewport: false ,
clip: {
x: 25 ,
y: 25 ,
width: 100 ,
height: 100 ,
},
});
expect(screenshot).toBeGolden('screenshot-offscreen-clip-2.png' );
});
it('should run in parallel' , async () => {
const {page, server} = await getTestState();
await page.setViewport({width: 500 , height: 500 });
await page.goto (server.PREFIX + '/grid.html' );
const promises = [];
for (let i = 0 ; i < 3 ; ++i) {
promises.push(
page.screenshot({
clip: {
x: 50 * i,
y: 0 ,
width: 50 ,
height: 50 ,
},
}),
);
}
const screenshots = await Promise.all(promises);
expect(screenshots[1 ]).toBeGolden('grid-cell-1.png' );
});
it('should take fullPage screenshots' , async () => {
const {page, server} = await getTestState();
await page.setViewport({width: 500 , height: 500 });
await page.goto (server.PREFIX + '/grid.html' );
const screenshot = await page.screenshot({
fullPage: true ,
});
expect(screenshot).toBeGolden('screenshot-grid-fullpage.png' );
});
it('should take fullPage screenshots without captureBeyondViewport' , async () => {
const {page, server} = await getTestState();
await page.setViewport({width: 500 , height: 500 });
await page.goto (server.PREFIX + '/grid.html' );
const screenshot = await page.screenshot({
fullPage: true ,
captureBeyondViewport: false ,
});
expect(screenshot).toBeGolden('screenshot-grid-fullpage-2.png' );
expect(page.viewport()).toMatchObject({width: 500 , height: 500 });
});
it('should run in parallel in multiple pages' , async () => {
const {server, context} = await getTestState();
const N = 2 ;
const pages = await Promise.all(
Array(N)
.fill(0 )
.map(async () => {
const page = await context.newPage();
await page.goto (server.PREFIX + '/grid.html' );
return page;
}),
);
const promises = [];
for (let i = 0 ; i < N; ++i) {
promises.push(
pages[i]!.screenshot({
clip: {x: 50 * i, y: 0 , width: 50 , height: 50 },
}),
);
}
const screenshots = await Promise.all(promises);
for (let i = 0 ; i < N; ++i) {
expect(screenshots[i]).toBeGolden(`grid-cell-${i}.png`);
}
await Promise.all(
pages.map(page => {
return page.close();
}),
);
});
it('should work with odd clip size on Retina displays' , async () => {
const {page} = await getTestState();
// Make sure documentElement height is at least 11px.
await page.setContent(`<div style="width: 11px; height: 11px;" >`);
const screenshot = await page.screenshot({
clip: {
x: 0 ,
y: 0 ,
width: 11 ,
height: 11 ,
},
});
expect(screenshot).toBeGolden('screenshot-clip-odd-size.png' );
});
it('should return base64' , async () => {
const {page, server} = await getTestState();
await page.setViewport({width: 500 , height: 500 });
await page.goto (server.PREFIX + '/grid.html' );
const screenshot = await page.screenshot({
encoding: 'base64' ,
});
expect(Buffer.from(screenshot, 'base64' )).toBeGolden(
'screenshot-sanity.png' ,
);
});
it('should take fullPage screenshots when defaultViewport is null' , async () => {
const {server, page} = state;
await page.goto (server.PREFIX + '/grid.html' );
const screenshot = await page.screenshot({
fullPage: true ,
});
expect(screenshot).toBeInstanceOf(Uint8Array);
});
it('should restore to original viewport size after taking fullPage screenshots when defaultViewport is null' , async () => {
const {server, page} = state;
const originalSize = await page.evaluate(() => {
return {width: window.innerWidth, height: window.innerHeight};
});
await page.goto (server.PREFIX + '/scrollbar.html' );
await page.screenshot({
fullPage: true ,
captureBeyondViewport: false ,
});
const size = await page.evaluate(() => {
return {width: window.innerWidth, height: window.innerHeight};
});
expect(page.viewport()).toBe(null );
expect(size.width).toBe(originalSize.width);
expect(size.height).toBe(originalSize.height);
});
});
describe('ElementHandle.screenshot' , function () {
it('should work' , async () => {
const {page, server} = await getTestState();
await page.setViewport({width: 500 , height: 500 });
await page.goto (server.PREFIX + '/grid.html' );
await page.evaluate(() => {
return window.scrollBy(50 , 100 );
});
using elementHandle = (await page.$('.box:nth-of-type(3)' ))!;
const screenshot = await elementHandle.screenshot();
expect(screenshot).toBeGolden('screenshot-element-bounding-box.png' );
});
it('should work with a null viewport' , async () => {
const {server, page} = state;
await page.goto (server.PREFIX + '/grid.html' );
await page.evaluate(() => {
return window.scrollBy(50 , 100 );
});
using elementHandle = await page.$('.box:nth-of-type(3)' );
assert (elementHandle);
const screenshot = await elementHandle.screenshot();
expect(screenshot).toBeTruthy();
});
it('should take into account padding and border' , async () => {
const {page} = await getTestState();
await page.setViewport({width: 500 , height: 500 });
await page.setContent(`
something above
<style>div {
border: 2 px solid blue;
background: green;
width: 50 px;
height: 50 px;
}
</style>
<div></div>
`);
using elementHandle = (await page.$('div' ))!;
const screenshot = await elementHandle.screenshot();
expect(screenshot).toBeGolden('screenshot-element-padding-border.png' );
});
it('should capture full element when larger than viewport' , async () => {
const {page} = await getTestState();
await page.setViewport({width: 500 , height: 500 });
await page.setContent(`
something above
<style>
:root {
scrollbar-width: none;
}
div.to-screenshot {
border: 1 px solid blue;
width: 600 px;
height: 600 px;
margin-left: 50 px;
}
</style>
<div class ="to-screenshot" ></div>
`);
using elementHandle = (await page.$('div.to-screenshot' ))!;
const screenshot = await elementHandle.screenshot();
expect(screenshot).toBeGolden(
'screenshot-element-larger-than-viewport.png' ,
);
expect(
await page.evaluate(() => {
return {
w: window.innerWidth,
h: window.innerHeight,
};
}),
).toEqual({w: 500 , h: 500 });
});
it('should scroll element into view' , async () => {
const {page} = await getTestState();
await page.setViewport({width: 500 , height: 500 });
await page.setContent(`
something above
<style>div.above {
border: 2 px solid blue;
background: red;
height: 1500 px;
}
div.to-screenshot {
border: 2 px solid blue;
background: green;
width: 50 px;
height: 50 px;
}
</style>
<div class ="above" ></div>
<div class ="to-screenshot" ></div>
`);
using elementHandle = (await page.$('div.to-screenshot' ))!;
const screenshot = await elementHandle.screenshot();
expect(screenshot).toBeGolden(
'screenshot-element-scrolled-into-view.png' ,
);
});
it('should work with a rotated element' , async () => {
const {page} = await getTestState();
await page.setViewport({width: 500 , height: 500 });
await page.setContent(`<!DOCTYPE html>
<div style="position:absolute;
top: 100 px;
left: 100 px;
width: 100 px;
height: 100 px;
background: green;
transform: rotateZ(200 deg);"> </div>`);
using elementHandle = (await page.$('div' ))!;
const screenshot = await elementHandle.screenshot();
expect(screenshot).toBeGolden('screenshot-element-rotate.png' );
});
it('should fail to screenshot a detached element' , async () => {
const {page} = await getTestState();
await page.setContent('<h1>remove this</h1>' );
using elementHandle = (await page.$('h1' ))!;
await page.evaluate(element => {
return element.remove();
}, elementHandle);
const screenshotError = await elementHandle.screenshot().catch (error => {
return error;
});
expect(screenshotError).toBeInstanceOf(Error);
expect(screenshotError.message).toMatch(
/Node is either not visible or not an HTMLElement|Node is detached from document/,
);
});
it('should not hang with zero width/height element' , async () => {
const {page} = await getTestState();
await page.setContent('<div style="width: 50px; height: 0"></div>' );
using div = (await page.$('div' ))!;
const error = await div.screenshot().catch (error_ => {
return error_;
});
expect(error.message).toBe('Node has 0 height.' );
});
it('should work for an element with fractional dimensions' , async () => {
const {page} = await getTestState();
await page.setContent(
'<div style="width:48.51px;height:19.8px;border:1px solid black;"></div>' ,
);
using elementHandle = (await page.$('div' ))!;
const screenshot = await elementHandle.screenshot();
expect(screenshot).toBeGolden('screenshot-element-fractional.png' );
});
it('should work for an element with an offset' , async () => {
const {page} = await getTestState();
await page.setContent(
'<!DOCTYPE html><div style="position:absolute; top: 10.3px; left: 20.4px;width:50.3px;height:20.2px;border:1px solid black;"></div>' ,
);
using elementHandle = (await page.$('div' ))!;
const screenshot = await elementHandle.screenshot();
expect(screenshot).toBeGolden('screenshot-element-fractional-offset.png' );
});
it('should work with webp' , async () => {
const {page, server} = await getTestState();
await page.setViewport({width: 100 , height: 100 });
await page.goto (server.PREFIX + '/grid.html' );
const screenshot = await page.screenshot({
type: 'webp' ,
});
expect(screenshot).toBeInstanceOf(Uint8Array);
});
it('should run in parallel in multiple pages' , async () => {
const {browser, server} = await getTestState();
const context = await browser.createBrowserContext();
const N = 2 ;
const pages = await Promise.all(
Array(N)
.fill(0 )
.map(async () => {
const page = await context.newPage();
await page.goto (server.PREFIX + '/grid.html' );
return page;
}),
);
const promises = [];
for (let i = 0 ; i < N; ++i) {
promises.push(
pages[i]!.screenshot({
clip: {x: 50 * i, y: 0 , width: 50 , height: 50 },
}),
);
}
const screenshots = await Promise.all(promises);
for (let i = 0 ; i < N; ++i) {
expect(screenshots[i]).toBeGolden(`grid-cell-${i}.png`);
}
await Promise.all(
pages.map(page => {
return page.close();
}),
);
await context.close();
});
it('should run in parallel with page.close()' , async () => {
const {browser} = await getTestState();
using context = await browser.createBrowserContext();
const page1 = await context.newPage();
const page2 = await context.newPage();
const screen1 = page1.screenshot();
const screen2 = page2.screenshot();
const close1 = screen1.then(() => {
return page1.close();
});
const close2 = screen2.then(() => {
return page2.close();
});
await screen1;
const page3 = await browser.newPage();
await page3.screenshot();
const close3 = page3.close();
await Promise.all([close1, close2, close3]);
});
it('should use element clip' , async () => {
const {page} = await getTestState();
await page.setViewport({width: 500 , height: 500 });
await page.setContent(`
something above
<style>div {
border: 2 px solid blue;
background: green;
width: 50 px;
height: 50 px;
}
</style>
<div></div>
`);
using elementHandle = (await page.$('div' ))!;
const screenshot = await elementHandle.screenshot({
clip: {
x: 10 ,
y: 10 ,
width: 20 ,
height: 20 ,
},
});
expect(screenshot).toBeGolden('screenshot-element-clip.png' );
});
});
describe('Cdp' , () => {
it('should use scale for clip' , async () => {
const {page, server} = await getTestState();
await page.setViewport({width: 500 , height: 500 });
await page.goto (server.PREFIX + '/grid.html' );
const screenshot = await page.screenshot({
clip: {
x: 50 ,
y: 100 ,
width: 150 ,
height: 100 ,
scale: 2 ,
},
});
expect(screenshot).toBeGolden('screenshot-clip-rect-scale2.png' );
});
it('should allow transparency' , async () => {
const {page, server} = await getTestState();
await page.setViewport({width: 100 , height: 100 });
await page.goto (server.EMPTY_PAGE);
const screenshot = await page.screenshot({omitBackground: true });
expect(screenshot).toBeGolden('transparent.png' );
});
it('should render white background on jpeg file' , async () => {
const {page, server} = await getTestState();
await page.setViewport({width: 100 , height: 100 });
await page.goto (server.EMPTY_PAGE);
const screenshot = await page.screenshot({
omitBackground: true ,
type: 'jpeg' ,
});
expect(screenshot).toBeGolden('white.jpg' );
});
it('should work in "fromSurface: false" mode' , async () => {
const {page, server} = await getTestState();
await page.setViewport({width: 500 , height: 500 });
await page.goto (server.PREFIX + '/grid.html' );
const screenshot = await page.screenshot({
fromSurface: false ,
});
expect(screenshot).toBeDefined();
});
});
});
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