tor-browser

The Tor Browser
git clone https://git.dasho.dev/tor-browser.git
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test-stepper.js (2871B)

      1 /* this source code form is subject to the terms of the mozilla public
      2 * license, v. 2.0. if a copy of the mpl was not distributed with this
      3 * file, you can obtain one at http://mozilla.org/mpl/2.0/. */
      4 
      5 "use strict";
      6 
      7 const { JSTracer } = ChromeUtils.importESModule(
      8  "resource://devtools/server/tracer/tracer.sys.mjs",
      9  { global: "contextual" }
     10 );
     11 
     12 let testFileContent;
     13 
     14 function traceFrame({ frame }) {
     15  const { script } = frame;
     16  const { lineNumber, columnNumber } = script.getOffsetMetadata(frame.offset);
     17 
     18  const { url } = script.source;
     19  const filename = url.substr(url.lastIndexOf("/") + 1);
     20  const line = testFileContent[lineNumber - 1];
     21  // Grey out the beginning of the line, before frame's column,
     22  // and display an arrow before displaying the rest of the line.
     23  const code =
     24    "\x1b[2m" +
     25    line.substr(0, columnNumber - 1) +
     26    "\x1b[0m" +
     27    "\u21A6 " +
     28    line.substr(columnNumber - 1);
     29 
     30  const position = (lineNumber + ":" + columnNumber).padEnd(7);
     31  logStep(`${filename} @ ${position} :: ${code}`);
     32 
     33  // Disable builtin tracer logging
     34  return false;
     35 }
     36 
     37 function logStep(message) {
     38  dump(` \x1b[2m[STEP]\x1b[0m ${message}\n`);
     39 }
     40 
     41 const tracingListener = {
     42  onTracingFrame: traceFrame,
     43  onTracingFrameStep: traceFrame,
     44 };
     45 
     46 exports.start = function (testGlobal, testUrl, pause) {
     47  const tracerOptions = {
     48    global: testGlobal,
     49    // Ensure tracing each execution within functions (and not only function calls)
     50    traceSteps: true,
     51    // Only trace the running test and nothing else
     52    filterFrameSourceUrl: testUrl,
     53  };
     54  testFileContent = readURI(testUrl).split("\n");
     55  // Only pause on each step if the passed value is a number,
     56  // otherwise we are only going to print each executed line in the test script.
     57  if (!isNaN(pause)) {
     58    // Delay each step by an amount of milliseconds
     59    tracerOptions.pauseOnStep = Number(pause);
     60    logStep(`Tracing all test script steps with ${pause}ms pause`);
     61    logStep(
     62      `/!\\ Be conscious about each pause releasing the event loop and breaking run-to-completion.`
     63    );
     64  } else {
     65    logStep(`Tracing all test script steps`);
     66  }
     67  logStep(
     68    `'\u21A6 ' symbol highlights what precise instruction is being called`
     69  );
     70  JSTracer.startTracing(tracerOptions);
     71  JSTracer.addTracingListener(tracingListener);
     72 };
     73 
     74 exports.stop = function () {
     75  JSTracer.stopTracing();
     76  JSTracer.removeTracingListener(tracingListener);
     77 };
     78 
     79 function readURI(uri) {
     80  const { NetUtil } = ChromeUtils.importESModule(
     81    "resource://gre/modules/NetUtil.sys.mjs",
     82    { global: "contextual" }
     83  );
     84  const stream = NetUtil.newChannel({
     85    uri: NetUtil.newURI(uri, "UTF-8"),
     86    loadUsingSystemPrincipal: true,
     87  }).open();
     88  const count = stream.available();
     89  const data = NetUtil.readInputStreamToString(stream, count, {
     90    charset: "UTF-8",
     91  });
     92 
     93  stream.close();
     94  return data;
     95 }