gecko-dev/dom/workers/test/WorkerDebugger.console_debugger.js

"use strict";

function ok(a, msg) {
  postMessage(JSON.stringify({ type: "status", what: !!a, msg }));
}

function is(a, b, msg) {
  ok(a === b, msg);
}

function finish() {
  postMessage(JSON.stringify({ type: "finish" }));
}

function magic() {
  console.log("Hello from the debugger script!");

  var foo = retrieveConsoleEvents();
  ok(Array.isArray(foo), "We received an array.");
  ok(foo.length >= 2, "At least 2 messages.");

  is(
    foo[0].arguments[0],
    "Can you see this console message?",
    "First message ok."
  );
  is(
    foo[1].arguments[0],
    "Can you see this second console message?",
    "Second message ok."
  );

  setConsoleEventHandler(function(consoleData) {
    is(consoleData.arguments[0], "Random message.", "Random message ok!");

    // The consoleEventHandler can be null.
    setConsoleEventHandler(null);

    finish();
  });
}

this.onmessage = function(event) {
  switch (event.data) {
    case "do magic":
      magic();
      break;
  }
};