RangeError: Maximum call stack size exceeded

[asapach]

Tell us about your runtime:

• QUnit version: 2.6.1
• What environment are you running QUnit in? (e.g., browser, Node): browser (Chrome) and Node
• How are you running QUnit? (e.g., script, testem, Grunt): either via cli, or karma-qunit, or in the browser

What are you trying to do?

We have a fairly large test suite with several thousand tests in it and with latest QUnit it takes forever to start and eventually it seems to run into a fairly impressive recursive call. This repro is an over-simplified version:

for (let i = 0; i < 100; i++) {
    QUnit.module('suite' + i, {
        beforeEach: function () {
            // do something
        },
        afterEach: function () {
            // do something
        }
    });

    for (let j = 0; j < 100; j++) {
        QUnit.test('test' + j, function (assert) {
            assert.ok(j !== 98);
        });
    }
}

What did you expect to happen?

All test suites should finish and report the results.

What actually happened?

QUnit fails before finishing the test run with the following exception:

Uncaught RangeError: Maximum call stack size exceeded
    at Array.join (native)
    at extractStacktrace (qunit.js:1074)
    at Test.run (qunit.js:1518)
    at qunit.js:1737
    at advanceTaskQueue (qunit.js:1129)
    at advance (qunit.js:1110)
    at advanceTestQueue (qunit.js:1155)
    at advance (qunit.js:1113)
    at advanceTestQueue (qunit.js:1155)
    at advance (qunit.js:1113)

[asapach]

The issue seems to have been introduced in v2.6.0

[trentmwillis]

Thanks for the report and reproduction! Definitely sounds like a bug. It was probably introduced with #1260.

[gkatsev]

Just noticed that 2.9.1 is out (thanks greenkeeper!) and I made a test branch that throws an error it seems to be fixed in it.

[Krinkle]

I can't reproduce this on qunit 2.9.2.

nobody@fresh$ qunit --version
2.9.2

nobody@fresh$ time qunit tmp.js
…
ok 9998 suite99 > test97
not ok 9999 suite99 > test98
  ---
  message: "failed, expected argument to be truthy, was: false"
  severity: failed
  actual: false
  expected: true
  stack:     at Object.<anonymous> (/Temp/tmp.js:13:20)
  ...
ok 10000 suite99 > test99
1..10000
# pass 9900
# skip 0
# todo 0
# fail 100

real	0m3.127s

It has the expected failure, and completes the ~ 10,000 times in about 3 seconds (this is inside a container, would presumably be quicker outside of that).