mocha as a library

Question

I would like to use mocha (the node.js test framework, not the ruby mocking library) as a library, rather than using the mocha executable to run my test.

Is it possible to run a mocha test this way? The examples all just call mocha libraries assuming they are already "require'd", and the mocha executable does all the "require-ing" ahead of time, but I would really prefer to do them explicitly in my script so that I can simply set +x on my script and call it directly.

Can I do something like this?

#!/usr/bin/env coffee
mocha = require 'mocha'
test = mocha.Test
suite = mocha.Suite
assert = require("chai").assert

thing = null

suite "Logging", () ->
  setup (done) ->
    thing = new Thing()
    done()
  test "the thing does a thing.", (done) ->
    thing.doThing () ->
      assert.equal thing.numThingsDone, 1
      done()
  teardown (done) ->
    thing = null
    done()

Answer 1

It's possible, but certainly not recommended.

Look at the mocha binary's source (specifically bin/_mocha) to get an idea of what it does. In particular, look at the run function. Everything it's using—Runner, Reporter, etc.—is exported by the mocha library, so there's nothing stopping you from reverse-engineering it.

Answer 2

This feature has since been added. I include an example below.

I got information from here:

You will need 2 files. One test, and one to run the test. You can mark runTest as executable, and set its output in the mocha options.

runTest.js

#!/usr/bin/env node

var Mocha = require('mocha'),
    fs    = require('fs'),
    path  = require('path');

var mocha = new Mocha(
{
  ui: 'tdd'     
});

mocha.addFile(
  path.join(__dirname, 'test.js')
);

mocha.run(function(failures){
  process.on('exit', function () {
    process.exit(failures);
  });
});

test.js

var assert = require('chai').assert

suite('Array', function(){
  setup(function(){});
  suite('#indexOf()', function(){
    test('should return -1 when not present', function(){
      assert.equal(-1, [1,2,3].indexOf(4));
    });
  });
});