Third party reporters

Anish Karandikar edited this page May 17, 2018 · 9 revisions

Mocha 1.3.0 allows you to define custom third-party reporters within your own test suite, or by using npm modules. For example if "lcov-reporter" was published to npm, you would simply add it to your package.json in devDependencies and use --reporter lcov-reporter.

Here is a minimalistic sample reporter, which you can use by executing: mocha --reporter my-reporter.js

// my-reporter.js
var mocha = require('mocha');
module.exports = MyReporter;

function MyReporter(runner) {, runner);
  var passes = 0;
  var failures = 0;

  runner.on('pass', function(test){
    console.log('pass: %s', test.fullTitle());

  runner.on('fail', function(test, err){
    console.log('fail: %s -- error: %s', test.fullTitle(), err.message);

  runner.on('end', function(){
    console.log('end: %d/%d', passes, passes + failures);

// To have this reporter "extend" a built-in reporter uncomment the following line:
// mocha.utils.inherits(MyReporter, mocha.reporters.Spec);

For details look at the implementations in lib/reporters/*.

Mocha provides the following events:

  • start: Execution started
  • end: Execution complete
  • suite: Test suite execution started
  • suite end: All tests (and sub-suites) have finished
  • test: Test execution started
  • test end: Test completed
  • hook: Hook execution started
  • hook end: Hook complete
  • pass: Test passed
  • fail: Test failed
  • pending: Test pending