Using external class during client side Mocha unit testing - javascript

I am running unit tests on a javascript class using Mocha using the follow methodology, firstly the test:
var base = require('../moduleone.js');
describe("some test", function() {
it("description", function() {
var check = base.toBeTested(dummyValue)
//test is here ...
});
});
the moduleone.js containing function to be tested:
function toBeTested(category){
//below I calling an assert function defined in moduletwo
//works fine when running in browser
assert(type(category)=='string','category is string type');
//more code..
return something
module.exports.toBeTested = toBeTested;
moduletwo.js:
function assert(outcome, description) {
//see code.tutsplus.com quick and easy javascript testing with assert
var li = outcome ? 'pass' : 'fail';
if (li == 'fail') {
console.log('FAIL: '+description);
}
else {
console.log('PASS: '+description);
}
}
The issue I have is mocha doesn't know anything about moduletwo and when the moduleone function calles the function in moduletwo mocha throws a ReferenceError: assert is not defined. How can I link all my dependencies so that mocha can see them?

In your moduleone.js be sure that you are requireing moduletwo.js to bring your assert function into scope for moduleone.js. Otherwise, you get a ReferenceError, not for any reasons with mocha, but because moduleone does not have access to assert.
// moduletwo.js
function assert(outcome, description) { /* your functionality */ }
module.exports = assert
// moduleone.js
var assert = require('./moduletwo')
function toBeTested(category) { /* your functionality that uses assert */ }
module.exports.toBeTested = toBeTested
Now, with regards to that tutorial. If you are following it to learn how to make an easy assert module, that is fine. But if you are trying to test some code that does something else, consider using an existing assertion library like chai. For example:
// example.test.js
var expect = require('chai').expect
var isValidCategory = require('./is-valid-category')
describe('isValidCategory(category)', function () {
it('validates string categories', function () {
expect(isValidCategory('A String Category')).to.be.true
})
it('does not validate non-string categories', function () {
expect(isValidCategory(['an', 'array', 'somehow'])).to.be.false
})
})
// is-valid-category.js
module.exports = function isValidCategory(category) {
return typeof category === 'string'
}

Related

Is it possible to create function inside `conf.js`?

Is it possible to create function which is used for every spec to test, for example login function inside the conf.js file or directly sendKeys from conf.js as from spec.js
From nodejs syntax, it supports to do that as following:
// conf.js
exports.config = {
// put config at here as usual
};
exports.login = function(username, password) {
browser.get('');
element.sendKeys('');
};
// spec.js
var login = require('./conf.js').login;
// actually, you can move the login function to another .js file to keep
// conf.js more dedicated on configuration purpose.
describe("A spec (with setup and tear-down)", function() {
it('', function(){
login('username', 'password')
});
});
But that is not a good practice. Because main test framework supports to do something before each test case. For jasmine it supplys beforeEach:
describe("A spec (with setup and tear-down)", function() {
var foo;
beforeEach(function() {
foo = 0;
foo += 1;
});
afterEach(function() {
foo = 0;
});
it("is just a function, so it can contain any code", function() {
expect(foo).toEqual(1);
});
it("can have more than one expectation", function() {
expect(foo).toEqual(1);
expect(true).toEqual(true);
});
});
At last, I can't see the benefit/advantage to do as you required.

mocha test (and babel) using global variables

I am writing library using es6, transpiling it with babel via webpack and npm.
The problem is, that my lib is dependent on some code, that I can not change but need to use. I don't know how to load var stuff (from the following example) in my tests so that it is visible for the module.
See the example:
external-stuff.js - this one can not be changed and is loaded before my lib is loaded on prod env.
var stuff = {
get some() { return "some"; }
get stuff() { return "stuff"; }
}
some-module.js - this is one of the modules in the library
export class foo {
static get whatever() { return stuff.some; }
static get whichever() { return stuff.stuff; }
}
test
import {foo} from "../src/foo.js";
let assert = require('assert');
describe('foo', function() {
describe('#whatever()', function() {
it("should do some", function () {
assert.equals(foo.whatever(), "some");
});
});
});
If I run this I get "ReferenceError: stuff is not defined"
I already tried to define "stuff" in before() hook, but no success.
In the end I found a solution that's 'good enough'. I am not sure it would be sufficient for some advanced library though.
I have created file called globals.js
var g = typeof(window) === 'undefined' ? global : window;
// Dependencies - add as many global stuff as needed
g.stuff= typeof(stuff) === 'undefined' ? {} : stuff;
And I import this 'es6module' at the beginning of test
import * as globals from "../lib/global/globals"
import {foo} from "../src/foo.js";
And then I use node-import npm module with which I load the global to the tests in beforeEach hook.
beforeEach(function () {
global.stuff = imports.module("lib/global/stuff.js").stuff;
});
This is perfect for unit testing because I can also mock stuff. And its even more awesome because this way I have a place where I 'define' global dependencies. It would be nice to improve on it and make it per es6modul dependencies... and build on it something fancy... ya know.. dependency injection.
complete test
require('node-import'); // +
import * as globals from "../lib/global/globals"; // +
import {foo} from "../src/foo.js";
let assert = require('assert');
describe('foo', function() {
beforeEach(function () { // +
global.stuff = imports.module("lib/global/stuff.js").stuff; // +
}); // +
describe('#whatever()', function() {
it("should do some", function () {
assert.equals(foo.whatever(), "some");
});
});
});

Mock a variable value in JS unit-tests

How could I mock(stub?) variable from external module in unit-tests?
I have a lib which would be running at browser as well as at node.js:
exports.Utils = (function (Config) {
return {
sum: function (val) {
return Config.defaultVal + val;
}
};
}(exports.Config));
Because tests run with only one (Utils.js) file, Config would be undefined here.
Tests runs in node.js enviroment.
var expect = require('chai').expect;
var Utils = require('./src/Utils.js').Utils;
describe("Test for Utils sum", function () {
it("example sum test", function () {
//How could I specify Config.defaultVal here?
expect(Utils.sum(1)).to.be.equal(2);
});
});
Perhaps I should use sinonjs, but I didn't find clear example for my case.

Test a function which uses document properties in qunit

I have a function like this which I would like to write a unit test for :
function A () {
var x = document.referrer;
//Do something with 'a'
}
I would like to write a unit test, to test this function. I'm using QUnit with sinon.js for stubs and mocks. Is there a way for me to mock the document object so that I can provide a value for the referrer and test my logic? I tried assigning a value to document.referrer in my setup function, but that didn't work
Update
This is the test which I'm trying :
module("Verify Referrer", {
setup : function () {
this.documentMock = sinon.mock(document);
this.documentMock.referrer = "http://www.test.com";
},
teardown : function () {
this.documentMock.restore();
}
});
test("UrlFilter test url in white list", function() {
equal(document.referrer, "http://www.test.com");
});
I also tried using stub

First test with mocha

I mactually trying to run my first unit test with mocha using this code :
var assert = require('assert');
var returnCool = function () {
return 1;
}
describe("Array contains", function () {
it('should return-1 when the value is not present', function () {
returnCool().should.equal(1);
});
});
The problem is that my code is actually failing everytime.
I tried with the sample in mocha website :
describe('Array', function(){
describe('#indexOf()', function(){
it('should return -1 when the value is not present', function(){
[1,2,3].indexOf(5).should.equal(-1);
[1,2,3].indexOf(0).should.equal(-1);
})
})
})
And it fails too.
What am I doing wrong ?
Thanks for advance
Looks like you are not calling your assertion library. You are currently calling .should() on an integer
You have included an assert library but are using should - style asserts. Either include should.js or use assert-style asserts (assert.equal([1,2,3].indexOf(5), -1))

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