在Nodejs中贯彻单元测试

目录

测试框架

测试接口

describe()

it()

before()

after()

beforeEach()

afterEach()

安装

npm install mocha -g

编写一个稳定可靠的模块

exports.limit = function (num) {
if (num < 0) {
return 0;
}
return num;
};

目录分配

lib

test

index.js

package.json

测试

var lib = require('index');

describe('module', function () {
describe('limit', function () {
it('limit should success', function () {
lib.limit(10);
});
});
});

结果

mocha

$ mocha

․

✔ 1 test complete (2ms)

断言库

加上断言

should

it('limit should success', function () {
lib.limit(10).should.be.equal(10);
});

需求变更

limit

异步测试

测试异步回调

exports.async = function (callback) {
setTimeout(function () {
callback(10);
}, 10);
};

describe('async', function () {
it('async', function (done) {
lib.async(function (result) {
done();
});
});
});

测试Promise

finally

eventually

fulfilled

fulfilledWith

rejected

rejectedWith

then

describe('should', function () {
describe('#Promise', function () {
it('should.reject', function () {
(new Promise(function (resolve, reject) {
reject(new Error('wrong'));
})).should.be.rejectedWith('wrong');
});

it('should.fulfilled', function () {
(new Promise(function (resolve, reject) {
resolve({username: 'jc', age: 18, gender: 'male'})
})).should.be.fulfilled().then(function (it) {
it.should.have.property('username', 'jc');
})
});
});
});

异步方法的超时支持

命令行式

mocha -t 10000

API式

describe('async', function () {
this.timeout(10000);
it('async', function (done) {
lib.async(function (result) {
done();
});
});
});

async

异常测试

getContent

exports.getContent = function (filename, callback) {
fs.readFile(filename, 'utf-8', callback);
};

简单Mock

describe("getContent", function () {
var _readFile;
before(function () {
_readFile = fs.readFile;
fs.readFile = function (filename, encoding, callback) {
process.nextTick(function () {
callback(new Error("mock readFile error"));
});
};
});
// it();
after(function () {
// 用完之后记得还原。否则影响其他case
fs.readFile = _readFile;
})
});

Mock库

muk

var fs = require('fs');
var muk = require('muk');

before(function () {
muk(fs, 'readFile', function(path, encoding, callback) {
process.nextTick(function () {
callback(new Error("mock readFile error"));
});
});
});
// it();
after(function () {
muk.restore();
});

测试私有方法

function _adding(num1, num2) {
return num1 + num2;
}

通过rewire导出方法

rewire

it('limit should return success', function () {
var lib = rewire('../lib/index.js');
var litmit = lib.__get__('limit');
litmit(10);
});

测试Web应用

/user

supertest

var express = require("express");
var request = require("supertest");
var app = express();

// 定义路由
app.get('/user', function(req, res){
res.send(200, { name: 'jerryc' });
});

describe('GET /user', function(){
it('respond with json', function(done){
request(app)
.get('/user')
.set('Accept', 'application/json')
.expect('Content-Type', /json/)
.expect(200)
.end(function (err, res) {
if (err){
done(err);
}
res.body.name.should.be.eql('jerryc');
done();
})
});
});

覆盖率

安装

$ npm install -g istanbul

覆盖率测试

istanbul cover _mocha

JerryC% istanbul cover _mocha

module
limit
✓ limit should success
async
✓ async
getContent
✓ getContent
add
✓ add

should
#Promise
✓ should.reject
✓ should fulfilled

6 passing (32ms)

================== Coverage summary ======================
Statements   : 100% ( 10/10 )
Branches     : 100% ( 2/2 )
Functions    : 100% ( 5/5 )
Lines        : 100% ( 10/10 )
==========================================================

istanbul cover

_mocha

[code]$ istanbul cover _mocha -- tests/test.sqrt.js -R spec

使用Makefile串起项目

TESTS = test/*.test.js
REPORTER = spec
TIMEOUT = 10000
JSCOVERAGE = ./node_modules/jscover/bin/jscover

test:
@NODE_ENV=test ./node_modules/mocha/bin/mocha -R $(REPORTER) -t $(TIMEOUT) $(TESTS)

test-cov: lib-cov
@LIB_COV=1 $(MAKE) test REPORTER=dot
@LIB_COV=1 $(MAKE) test REPORTER=html-cov > coverage.html

lib-cov:
@rm -rf ./lib-cov
@$(JSCOVERAGE) lib lib-cov

.PHONY: test test-cov lib-cov

make test
make test-cov

持续集成，Travis-cli

npm test

.travis.yml

language: node_js
node_js:
- "0.12"

一些观点

彩蛋

faker

整理

Nodejs的单元测试工具

参考