angular进行简单单元测试的实现方法实例-百家乐凯发k8

前言

之前对单元测试的认知就是复杂，难搞，思路有，就是不知道怎样去实现，最近一次开会解决问题的过程中，发现原来单元测试可以十分简单，简单到几行代码就能实现。

示例

下面代码实现的功能是，判断课程所在的学院 college是否在用户所有的学院array colleges中，如果存在，变量show赋值为true，不存在，则赋值为false，如果college为undefined或者null，也赋值为true。

/**
 * 观察课程学院是否与用户所在学院相同
 * @param college 课程学院
 * @param colleges 用户学院
 */
 public whethershow(college: { id: number }, colleges: array<{ id: number }>) {
 assert.notnull(college, 'college未定义');
 const collegeid = college.id;
 let show = colleges != null && colleges && colleges.length > 0 ? false : true;
 if (colleges != null) {
 colleges.foreach(selectcollege => {
 if (collegeid === selectcollege.id) {
  show = true;
 }
 });
 }
 return show;
 }

要对该方法进行单元测试，思路就是传值进去进行对比，重点在于传值，用之前的思路就是，定义college和colleges,然后进行对比：

it('is show', () => {
 const course = new course({id: 1})
 const collegeone = new college({id: 1});
 const collegetwo = new college({id: 2});
 component.colleges = [];
 expect(component.whethershow(course,component.colleges)).tobe(true);
 component.colleges = undefined;
 expect(component.whethershow(course,component.colleges)).tobe(true);
 component.colleges = [collegeone];
 expect(component.whethershow(course,component.colleges)).tobe(true);
 component.colleges = [collegetwo];
 expect(component.whethershow(course,component.colleges)).tobe(false);
 component.colleges = [collegeone, collegetwo];
 expect(component.whethershow(course,component.colleges)).tobe(true);
 });

通过控制台的信息可以发现，无论是null还是undefined，都是可以通过的，后来老师提供了新的思路，既然要测试的是功能，就不要管怎么传的，可以不用传对象，然后就有了下面的写法：

it('is show', () => {
 expect(component.whethershow({id: 1}, null)).tobe(true);
 expect(component.whethershow({id: 1}, undefined)).tobe(true);
 expect(component.whethershow({id: 1}, [])).tobe(true);
 expect(component.whethershow({id: 1}, [{id: 2}, {id: 3}])).tobe(false);
 expect(component.whethershow({id: 1}, [{id: 1}, {id: 2}, {id: 3}])).tobe(true);
 expect(component.whethershow({id: 1}, [{id: 2}, {id: 3}, {id: 1}])).tobe(true);
 });

值传进去了，方法也能判断了，比起之前的写法简直要好太多，而且对于一些方法来说，这种方法省力不少，尤其是对多种情况进行测试，要进行多个变量的定义：

/**
 * 判断查询的关键字是否课程代码或名称中
 * @param course 课程
 * @param searchkey 查询关键字
 */
 public iscodeornamecontainssearchkey(course: { code: string, name: string }, searchkey: string) {
 return searchkey === null
  || course.code.tolowercase().indexof(searchkey.tolowercase()) !== -1
  || course.name.tolowercase().indexof(searchkey.tolowercase()) !== -1;
 }

该方法实现的是通过课程名称或代码进行查询操作，通过对查询关键字和课程名称或代码进行对比实现该功能，要考虑以下几种情况：查询关键字为null、查询关键字与课程名称或代码部分完全不相同、查询关键字与课程名称或代码部分相同、查询关键字与课程名称或代码完全相同、查询关键字包含课程名称或代码。

如果用旧思想进行测试：

it('iscodeornamecontainssearchkey', () => {
 const courseone = new course({code: '', name: ''});
 const coursetwo = new course({code: '222', name: ''});
 const coursethree = new course({code: '', name: '222'});
 const coursefour = new course({code: '222', name: '222'});
 expect(component.iscodeornamecontainssearchkey(courseone, null));
 expect(component.iscodeornamecontainssearchkey(courseone, ''));
 expect(component.iscodeornamecontainssearchkey(coursetwo, ''));
 expect(component.iscodeornamecontainssearchkey(coursetwo, '1111'));
 expect(component.iscodeornamecontainssearchkey(coursetwo, '22'));
 expect(component.iscodeornamecontainssearchkey(coursetwo, '222'));
 expect(component.iscodeornamecontainssearchkey(coursetwo, '2222'));
 expect(component.iscodeornamecontainssearchkey(coursethree, ''));
 expect(component.iscodeornamecontainssearchkey(coursethree, '1111'));
 expect(component.iscodeornamecontainssearchkey(coursethree, '22'));
 expect(component.iscodeornamecontainssearchkey(coursethree, '222'));
 expect(component.iscodeornamecontainssearchkey(coursethree, '2222'));
 expect(component.iscodeornamecontainssearchkey(coursefour, ''));
 expect(component.iscodeornamecontainssearchkey(coursefour, '1111'));
 expect(component.iscodeornamecontainssearchkey(coursefour, '22'));
 expect(component.iscodeornamecontainssearchkey(coursefour, '222'));
 expect(component.iscodeornamecontainssearchkey(coursefour, '2222'));
 
});

如果使用新思想：

it('iscodeornamecontainssearchkey', () => {
 expect(component.iscodeornamecontainssearchkey({code: '', name: ''}, null)).tobe(true);
 expect(component.iscodeornamecontainssearchkey({code: '', name: ''}, '')).tobe(true);
 expect(component.iscodeornamecontainssearchkey({code: '222', name: ''}, '')).tobe(true);
 expect(component.iscodeornamecontainssearchkey({code: '222', name: ''}, '1111')).tobe(false);
 expect(component.iscodeornamecontainssearchkey({code: '222', name: ''}, '22')).tobe(true);
 expect(component.iscodeornamecontainssearchkey({code: '222', name: ''}, '222')).tobe(true);
 expect(component.iscodeornamecontainssearchkey({code: '222', name: ''}, '2222')).tobe(false);
 expect(component.iscodeornamecontainssearchkey({code: '', name: '222'}, '')).tobe(true);
 expect(component.iscodeornamecontainssearchkey({code: '', name: '222'}, '1111')).tobe(false);
 expect(component.iscodeornamecontainssearchkey({code: '', name: '222'}, '22')).tobe(true);
 expect(component.iscodeornamecontainssearchkey({code: '', name: '222'}, '222')).tobe(true);
 expect(component.iscodeornamecontainssearchkey({code: '', name: '222'}, '2222')).tobe(false);
 expect(component.iscodeornamecontainssearchkey({code: '222', name: '222'}, '')).tobe(true);
 expect(component.iscodeornamecontainssearchkey({code: '222', name: '222'}, '1111')).tobe(false);
 expect(component.iscodeornamecontainssearchkey({code: '222', name: '222'}, '22')).tobe(true);
 expect(component.iscodeornamecontainssearchkey({code: '222', name: '222'}, '222')).tobe(true);
 expect(component.iscodeornamecontainssearchkey({code: '222', name: '222'}, '2222')).tobe(false);
 });

设想一下自己看到他人写的测试代码，如果所需要的变量很少，courseone等等能满足需求，看着也没问题，但是当变量很多的时候，估计写测试的都会忘记每个变量的属性值，更不用说看的人，而且，使用下面的方法写的代码，所需字段以及字段值一目了然，一行代码就能体现所有信息，看着也赏心悦目。

总结

简单的单元测试写起来真的要简单很多，而且感觉比之前的要优雅很多，看起来真的挺整洁的，整整齐齐的看着很舒服，感谢潘老师的指导，也感谢小伙伴们给予的帮助。