import { Viewport } from "puppeteer" ; import type PercySnapshot from "@percy/puppeteer" ; import { Browser , launchChrome } from "../browser/chrome" ; import { debugLogger } from "../logger" ; import { ScreenshotRenderer } from "./api" ; const logDebug = debugLogger ( "PercyScreenshotRenderer" ) ; /**
 * A screenshot renderer that uses Percy to take and compare screenshots.
 */ export class PercyScreenshotRenderer implements ScreenshotRenderer { private browser : Browser | null = null ; constructor ( ) { } async start ( ) { logDebug ( `start() initiated.` ) ; logDebug ( `Launching Chrome browser.` ) ; this . browser = await launchChrome ( ) ; logDebug ( `Chrome browser launched.` ) ; } async stop ( ) { logDebug ( `stop() initiated.` ) ; if ( this . browser ) { logDebug ( `Closing Chrome browser.` ) ; await this . browser . close ( ) ; logDebug ( `Chrome browser closed.` ) ; } else { logDebug ( `No Chrome browser found.` ) ; } } async render ( name , url , viewport ? ) { logDebug ( `render() invoked with (name = ${ name }, url = ${ url }).` ) ; if ( ! this . browser ) { throw new Error ( "Browser was not launched successfully." ) ; } const page = await this . browser . newPage ( ) ; await page . goto ( url ) ; let percySnapshot ; try { percySnapshot = ( await import ( "@percy/puppeteer" ) ) . default ; } catch ( e ) { throw new Error ( `Please install the '@percy/puppeteer' package:
    
    Using NPM:
    $ npm install -D @percy/puppeteer
    
    Using Yarn:
    $ yarn add -D @percy/puppeteer` ) ; } await percySnapshot ( page , name , viewport && { widths : [ viewport . width / ( viewport . deviceScaleFactor || 1 ) ] , } ) ; } }