zqzhang/testing-in-nodejs

Testing in Nodejs

The original source code is cheated from Node.js Recipes.

The full text for the sample code is Chapter 11 Testing in Node.js.

Many thanks to the author Cory Gackenheimer and the publisher Apress.

Here I just want to try the sample code for self study.

My problems

Need to test some Node.js based JavaScript APIs on a platform without npm support. Thus need to figure out:

• which testing framework is suitable, and
• how to enable the framework on the platform.

Node.js assert

Creating Tests with the Node.js assert Module.

The Node.js assert testing module, imported using require(‘assert’), is utilized for internal Node.js tests and has become the basis for many third-party testing implementations. The assert module is created in such a way that if a particular condition is not met for your testing needs, it will throw an assertion error. If all passes, the Node.js process will exit as expected.

Suppose Node.js is supported. Run this command:

node assert.js

Nodeunit

Creating Tests with nodeunit.

Nodeunit provides the same API as the assert module with the addition of two methods, .done() and .expect(amount). To implement a test with nodeunit you need to export the tests from a module. The format of this export can help you to group your tests.

To call a nodeunit test, you must first install nodeunit.

npm install –g nodeunit

nodeunit nodeunit.js

If you meet "Error: Cannot find module 'nodeunit'", you can export NODE_PATH to be the output of npm root -g. See this.

export NODE_PATH=`npm root -g`

Mocha

Creating Tests with mocha.

Mocha is a testing framework that can utilize any assertion module that you choose. It allows you to name your test suite and specific case in order to see the desired output from your tests.

describe('Test suite', function() {

    describe('test-case', function() {

        // tests go here
        it('should return true that 3 equals "3"', function() {

            assert.equal(three, '3', '3 equals "3"');

        });

    });

});

There are two main ways in which you can tell Mocha to perform its tests.

npm install –g mocha

mocha mocha.js

mocha