Timeouts

Timeouts

Suite-level

Suite-level timeouts may be applied to entire test “suites”, or disabled via this.timeout(0). This will be inherited by all nested suites and test-cases that do not override the value.

describe("a suite of tests", function () {
  this.timeout(500);

  it("should take less than 500ms", function (done) {
    setTimeout(done, 300);
  });

  it("should take less than 500ms as well", function (done) {
    setTimeout(done, 250);
  });
});

Test-level

Test-specific timeouts may also be applied, or the use of this.timeout(0) to disable timeouts all together:

it("should take less than 500ms", function (done) {
  this.timeout(500);
  setTimeout(done, 300);
});

Hook-level

Hook-level timeouts may also be applied:

describe("a suite of tests", function () {
  beforeEach(function (done) {
    this.timeout(3000); // A very long environment setup.
    setTimeout(done, 2500);
  });
});

Again, use this.timeout(0) to disable the timeout for a hook.

Note

In v3.0.0 or newer, a parameter passed to this.timeout() greater than the maximum delay value will cause the timeout to be disabled.

Note

In v8.0.0 or newer, this.enableTimeouts() has been removed.

Caution

With async tests if you disable timeouts via this.timeout(0) and then do not call done(), your test will exit silently.

Diffs

Mocha supports the err.expected and err.actual properties of any thrown AssertionErrors from an assertion library. Mocha will attempt to display the difference between what was expected, and what the assertion actually saw. Here’s an example of a “string” diff using --inline-diffs: