test_onGarbageCollection-01.js

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// Test basic usage of onGarbageCollection

const root = newGlobal();

const dbg = new Debugger();

const wrappedRoot = dbg.addDebuggee(root)

const NUM_SLICES = root.NUM_SLICES = 10;

let fired = false;

let slicesFound = 0;

Services.prefs.setBoolPref("security.allow_eval_with_system_principal", true);

registerCleanupFunction(() => {

  Services.prefs.clearUserPref("security.allow_eval_with_system_principal");

});

dbg.memory.onGarbageCollection = data => {

  fired = true;

  print("Got onGarbageCollection: " + JSON.stringify(data, null, 2));

  equal(typeof data.reason, "string");

  equal(typeof data.nonincrementalReason == "string" || data.nonincrementalReason === null,

        true);

  let lastStartTimestamp = 0;

  for (let i = 0; i < data.collections.length; i++) {

    let slice = data.collections[i];

    equal(slice.startTimestamp >= lastStartTimestamp, true);

    equal(slice.startTimestamp <= slice.endTimestamp, true);

    lastStartTimestamp = slice.startTimestamp;

  equal(data.collections.length >= 1, true);

  slicesFound += data.collections.length;

function run_test() {

  do_test_pending();

  root.eval(

    this.allocs = [];

    // GC slices

    for (var i = 0; i < NUM_SLICES; i++) {

      this.allocs.push({});

      gcslice();

    // Full GC

    this.allocs.push({});

    gc();

);

  executeSoon(() => {

    equal(fired, true, "The GC hook should have fired at least once");

    // NUM_SLICES + 1 full gc + however many were triggered naturally (due to

    // whatever zealousness setting).

    print("Found " + slicesFound + " slices");

    equal(slicesFound >= NUM_SLICES + 1, true);

    do_test_finished();

});