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// @ts-check
import { Browser } from "puppeteer";import { ensureDir } from "std/fs/mod.ts";import { fromFileUrl } from "std/path/mod.ts";import { assertEquals } from "std/testing/asserts.ts";
const projectDirUrl = new URL("../", import.meta.url);const coverageDirUrl = new URL(".coverage/", projectDirUrl);
/** * Creates a new Puppeteer page for testing served project files with script * coverage enabled. * @param {Browser} browser Puppeteer browser. * @param {URL} projectFilesOriginUrl Project files origin URL. * @param {(page: import("puppeteer").Page) => void | Promise<void>} callback *   Receives the Puppeteer page, ready for testing. */export default async function testPuppeteerPage(  browser,  projectFilesOriginUrl,  callback,) {  if (!(browser instanceof Browser)) {    throw new TypeError(      "Argument 1 `browser` must be a Puppeteer `Browser` instance.",    );  }
  if (!(projectFilesOriginUrl instanceof URL)) {    throw new TypeError(      "Argument 3 `projectFilesOriginUrl` must be a `URL` instance.",    );  }
  if (typeof callback !== "function") {    throw new TypeError("Argument 5 `callback` must be a function.");  }
  const page = await browser.newPage();
  try {    /** @type {Array<Error>} */    const pageErrors = [];
    page.on("pageerror", (error) => {      pageErrors.push(error);    });
    page.on("console", async (message) => {      const type = message.type();      const summary = `Puppeteer page console ${type}`;
      switch (type) {        case "error":        case "info":        case "log":        case "warning": {          const args = await Promise.all(            message.args().map((arg) =>              arg.executionContext().evaluate(                /** @param {unknown} value */                (value) => value instanceof Error ? value.message : value,                arg,              )            ),          );
          // Workaround Puppeteer not providing the arguments when the console          // method was called internally by Puppeteer instead of page code.          if (!args.length) {            const text = message.text();            if (text) args.push(text);          }
          console.group(`${summary}:`);          console[type === "warning" ? "warn" : type](...args);          console.groupEnd();
          break;        }
        default:          console.log(`${summary} occurred.`);      }    });
    await page.coverage.startJSCoverage();
    try {      await callback(page);    } finally {      // This private API is the only way to get the raw V8 script coverage      // result, see:      // https://github.com/puppeteer/puppeteer/issues/2136#issuecomment-657080751      const pageClient = page._client();      const { result } = await pageClient.send("Profiler.takePreciseCoverage");      await page.coverage.stopJSCoverage();
      await ensureDir(fromFileUrl(coverageDirUrl));
      /** @type {Array<Promise<void>>} */      const writes = [];
      for (const scriptCoverage of result) {        if (scriptCoverage.url.startsWith(projectFilesOriginUrl.href)) {          writes.push(            Deno.writeTextFile(              new URL(`${crypto.randomUUID()}.json`, coverageDirUrl),              JSON.stringify({                ...scriptCoverage,                url: projectDirUrl.href +                  scriptCoverage.url.slice(projectFilesOriginUrl.href.length),              }),            ),          );        }      }
      await Promise.all(writes);    }
    assertEquals(pageErrors, []);  } finally {    await page.close();  }}