It
Overview
It is a BDD testing framework for node.js. The premise behind it is to be as lightweight as possible while making testing easy and fun to do.
Installation
npm install it
To use the it executable
npm install -g it
##Usage
It contains the following functions to write and run tests.
- describe - The name of object/context you are testing.
- should - the action that you are testing/should happen.
- beforeAll - an action that should happen before all tests in the current context.
- afterAll - an action that should happen after all tests in the current context.
- beforeEach - an action that should happen before each test in the current context.
- afterEach - an action that should happen before each test in the current context.
###Synchronous tests
Writing synchronous tests in It is extremely simple. So lets start off with an example.
Lets assume we have a Person Object
var Person = function (name, age) {
this.name = name;
this.age = age;
this.getOlder = function (years) {
if (years > 0) {
this.age = this.age + years;
}
};
};
The first tests we could run on person could be testing the setting of name and age.
var it = require("../index"),
assert = require("assert");
it.describe("Person", function (it) {
it.should("set set name", function () {
var person = new Person("bob", 1);
assert.equal(person.name, "bob");
});
it.should("set set age", function () {
var person = new Person("bob", 1);
assert.equal(person.age, 1);
});
});
Notice we use the it passed back to the describe callback.
Next we could test different scenarios of Person#getOlder
var it = require("../index"),
assert = require("assert");
it.describe("Person", function (it) {
it.describe("#getOlder", function (it) {
it.should("accept positive numbers", function () {
var person = new Person("bob", 1);
person.getOlder(2);
assert.equal(person.age, 3);
});
it.should("not apply negative numbers", function () {
var person = new Person("bob", 1);
person.getOlder(-2);
assert.equal(person.age, 1);
});
});
});
In this example we are describing the getOlder method and run different tests against it.
Notice the it passed back is used again.
You may nest tests as deep as you like as long as you remember to use the proper it.
it.describe("#getOlder nested", function (it) {
it.describe("with positive numbers", function (it) {
it.should("work", function () {
var person = new Person("bob", 1);
person.getOlder(2);
assert.equal(person.age, 3);
});
});
it.describe("with negative numbers", function () {
it.should("not work", function () {
var person = new Person("bob", 1);
person.getOlder(-2);
assert.equal(person.age, 1);
});
});
});
###Asynchronous tests
Writing asynchronous tests in It is just as easy as writing synchronous tests.
Lets modify Person to make get older async
var Person = function (name, age) {
this.name = name;
this.age = age;
this.getOlder = function (years, cb) {
setTimeout(function () {
this.age = this.age + years;
cb.call(this, null, this);
}.bind(this), years * 500);
};
};
Now that getOlder is async lets test it
it.describe("#getOlder", function (it) {
it.should("accept positive numbers", function (next) {
var person = new Person("bob", 1);
person.getOlder(2, function (err, person) {
assert.equal(person.age, 3);
next();
});
});
it.should("not apply negative numbers", function () {
var ret = new comb.Promise();
var person = new Person("bob", 1);
person.getOlder(-2, function (err, person) {
assert.equal(person.age, 1);
ret.callback();
});
return ret;
});
});
So in the above example the first should invocation accepts a next argument which is a function that should
be called when the current test is done. If next's function signature is next(err, ...). So if next is invoked
with a first argument other than null or undefined then it is assumed that the test errored.
The second should used a promise as a return value if you have used comb or any other framework that uses
Promises then this will feel pretty natural to you. The test will wait for the promise to resolve before
continuing any other tests.
###Running Tests
To run tests there are two options the it executable
Options
- -d, --directory : The root directory of your tests
- -r, --reporter : The reporter to use when running the tests
- --cov-html : create coverage output in html, if an output path is included then the file will be written to that file otherwise it will defalt to
./coverage.html
- --reporters : Display a list of reporters that are available
- -h, --help : Displays help.
To run an entire suite
it -d ./mytests -r dotmatrix
To run an individual test
it ./mytests/person.test.js
You can alternatively run the test directly
it.describe("A Person", function(it){
it.should("set set name", function () {
var person = new Person("bob", 1);
assert.equal(person.name, "bob");
});
it.should("set set age", function () {
var person = new Person("bob", 1);
assert.equal(person.age, 1);
});
it.run();
});
###Code Coverage
If you use node-jscoverage to generate coverage then by default it
will output a coverage report. You may also output coverage to an HTML
file by passing in the --cov-html
flag to the executable. For example out put see patio test coverage.
###Reporters
It currently has two reporters built in
For the above tests the output for spec should look as follows
Person
√ should set set name (0ms)
√ should set set age (0ms)
#getOlder
√ should accept positive numbers (1002ms)
√ should not apply negative numbers (0ms)
Finished in 1.002s
4 examples, 0 errors
With dot matrix
Person
....
Finished in 1.002s
4 examples, 0 errors
###Assert extensions
The following methods are added to assert for convenience
- lengthOf - assert the length of an array
- isTrue - assert that a value is true
- isFalse - assert that a value is false
- isRegExp - assert that a value is a Regular Expression
- isArray - assert that a value is an Array
- isHash - assert that a value is a plain object
- isObject - assert that a value is a object
- isNumber - assert that a value is a Number
- isDate - assert that a value is a Date
- isBoolean - assert that a value is a Boolean
- isString - assert that a value is a String
- isUndefined - assert that a value is undefined
- isUndefinedOrNull - assert that a value is undefined or null
- isPromiseLike - assert that a value is Promise like (contains the funtions "then", "addErrback", and "addCallback")
- isFunction - assert that a value is a function
- isNull - assert that a value is null
- isNotNull - assert that a value is not null
- instanceOf - assert that a value is an instanceof a particular object
License
MIT https://github.com/doug-martin/it/raw/master/LICENSE
Meta
- Code:
git clone git://github.com/doug-martin/it.git