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Mocha Testing Framework

Qualified supports the Mocha testing framework, in a BDD or TDD setup.

The following is a Mocha TDD example on how to use the framework using the built in Node.js assertion library:

/// <reference path="/runner/typings/node/index.d.ts" />
/// <reference path="/runner/typings/mocha/index.d.ts" />
/// <reference path="/runner/typings/chai/index.d.ts" />
var assert = require("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));
    });
  });
});

Assertions

Mocha allows you to use any assertion library you want and so does not auto-require a certain library for you by default.

Chai

We recommend that you use the Chai BDD/TDD assertion library. It supports the following assertion styles:

Should

require("chai").should();

foo.should.be.a('string');
foo.should.equal('bar');
foo.should.have.length(3);
tea.should.have.property('flavors')
  .with.length(3);

Expect

var expect = require("chai").expect;

expect(foo).to.be.a('string');
expect(foo).to.equal('bar');
expect(foo).to.have.length(3);
expect(tea).to.have.property('flavors')
  .with.length(3);

Assert

var assert = require("chai").assert;

assert.typeOf(foo, 'string');
assert.equal(foo, 'bar');
assert.lengthOf(foo, 3)
assert.property(tea, 'flavors');
assert.lengthOf(tea.flavors, 3);

Loaded NPM Packages

The following test related packages are loaded into the VM and available for use:

Learn More

You can learn more on the Mocha website.

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