### 彪哥

爱好前端

- 初识 TypeScript

- TypeScript 常用语法

- ts-axios 项目初始化

- ts-axios 基础功能实现

- ts-axios 异常情况处理

- ts-axios 接口扩展

- ts-axios 拦截器实现

- ts-axios 配置化实现

- ts-axios 取消功能实现

- ts-axios 更多功能实现

- ts-axios 单元测试

  - 前言
  - Jest 安装和配置
  - 辅助模块单元测试
  - 请求模块单元测试
  - headers 模块单元测试
  - Axios 实例模块单元测试
  - 拦截器模块单元测试
    - 测试代码编写
  - mergeConfig 模块单元测试
  - 请求取消模块单元测试
  - 剩余模块单元测试

- ts-axios 部署与发布

- 《TypeScript 从零实现 axios》
- ts-axios 单元测试

HuangYi
2020-01-05
目录

# 拦截器模块单元测试

# # 拦截器模块单元测试

拦截器是 `ts-axios` 库一个非常实用的功能，接下来我们来编写它的测试代码。

## # 测试代码编写

`test/interceptor.spec.ts`：

    import axios, { AxiosRequestConfig, AxiosResponse } from '../src/index'
    import { getAjaxRequest } from './helper'

    describe('interceptors', () => {
      beforeEach(() => {
        jasmine.Ajax.install()
      })

      afterEach(() => {
        jasmine.Ajax.uninstall()
      })

      test('should add a request interceptor', () => {
        const instance = axios.create()

        instance.interceptors.request.use((config: AxiosRequestConfig) => {
          config.headers.test = 'added by interceptor'
          return config
        })

        instance('/foo')

        return getAjaxRequest().then(request => {
          expect(request.requestHeaders.test).toBe('added by interceptor')
        })
      })

      test('should add a request interceptor that returns a new config object', () => {
        const instance = axios.create()

        instance.interceptors.request.use(() => {
          return {
            url: '/bar',
            method: 'post'
          }
        })

        instance('/foo')

        return getAjaxRequest().then(request => {
          expect(request.method).toBe('POST')
          expect(request.url).toBe('/bar')
        })
      })

      test('should add a request interceptor that returns a promise', done => {
        const instance = axios.create()

        instance.interceptors.request.use((config: AxiosRequestConfig) => {
          return new Promise(resolve => {
            setTimeout(() => {
              config.headers.async = 'promise'
              resolve(config)
            }, 10)
          })
        })

        instance('/foo')

        setTimeout(() => {
          getAjaxRequest().then(request => {
            expect(request.requestHeaders.async).toBe('promise')
            done()
          })
        }, 100)
      })

      test('should add multiple request interceptors', () => {
        const instance = axios.create()

        instance.interceptors.request.use(config => {
          config.headers.test1 = '1'
          return config
        })
        instance.interceptors.request.use(config => {
          config.headers.test2 = '2'
          return config
        })
        instance.interceptors.request.use(config => {
          config.headers.test3 = '3'
          return config
        })

        instance('/foo')

        return getAjaxRequest().then(request => {
          expect(request.requestHeaders.test1).toBe('1')
          expect(request.requestHeaders.test2).toBe('2')
          expect(request.requestHeaders.test3).toBe('3')
        })
      })

      test('should add a response interceptor', done => {
        let response: AxiosResponse
        const instance = axios.create()

        instance.interceptors.response.use(data => {
          data.data = data.data + ' - modified by interceptor'
          return data
        })

        instance('/foo').then(data => {
          response = data
        })

        getAjaxRequest().then(request => {
          request.respondWith({
            status: 200,
            responseText: 'OK'
          })

          setTimeout(() => {
            expect(response.data).toBe('OK - modified by interceptor')
            done()
          }, 100)
        })
      })

      test('should add a response interceptor that returns a new data object', done => {
        let response: AxiosResponse
        const instance = axios.create()

        instance.interceptors.response.use(() => {
          return {
            data: 'stuff',
            headers: null,
            status: 500,
            statusText: 'ERR',
            request: null,
            config: {}
          }
        })

        instance('/foo').then(res => {
          response = res
        })

        getAjaxRequest().then(request => {
          request.respondWith({
            status: 200,
            responseText: 'OK'
          })

          setTimeout(() => {
            expect(response.data).toBe('stuff')
            expect(response.headers).toBeNull()
            expect(response.status).toBe(500)
            expect(response.statusText).toBe('ERR')
            expect(response.request).toBeNull()
            expect(response.config).toEqual({})
            done()
          }, 100)
        })
      })

      test('should add a response interceptor that returns a promise', done => {
        let response: AxiosResponse
        const instance = axios.create()

        instance.interceptors.response.use(data => {
          return new Promise(resolve => {
            // do something async
            setTimeout(() => {
              data.data = 'you have been promised!'
              resolve(data)
            }, 10)
          })
        })

        instance('/foo').then(res => {
          response = res
        })

        getAjaxRequest().then(request => {
          request.respondWith({
            status: 200,
            responseText: 'OK'
          })

          setTimeout(() => {
            expect(response.data).toBe('you have been promised!')
            done()
          }, 100)
        })
      })

      test('should add multiple response interceptors', done => {
        let response: AxiosResponse
        const instance = axios.create()

        instance.interceptors.response.use(data => {
          data.data = data.data + '1'
          return data
        })
        instance.interceptors.response.use(data => {
          data.data = data.data + '2'
          return data
        })
        instance.interceptors.response.use(data => {
          data.data = data.data + '3'
          return data
        })

        instance('/foo').then(data => {
          response = data
        })

        getAjaxRequest().then(request => {
          request.respondWith({
            status: 200,
            responseText: 'OK'
          })

          setTimeout(() => {
            expect(response.data).toBe('OK123')
            done()
          }, 100)
        })
      })

      test('should allow removing interceptors', done => {
        let response: AxiosResponse
        let intercept
        const instance = axios.create()

        instance.interceptors.response.use(data => {
          data.data = data.data + '1'
          return data
        })
        intercept = instance.interceptors.response.use(data => {
          data.data = data.data + '2'
          return data
        })
        instance.interceptors.response.use(data => {
          data.data = data.data + '3'
          return data
        })

        instance.interceptors.response.eject(intercept)
        instance.interceptors.response.eject(5)

        instance('/foo').then(data => {
          response = data
        })

        getAjaxRequest().then(request => {
          request.respondWith({
            status: 200,
            responseText: 'OK'
          })

          setTimeout(() => {
            expect(response.data).toBe('OK13')
            done()
          }, 100)
        })
      })
    })

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258

运行测试后我们发现在测试用例 `should add a request interceptor that returns a new config object` 报错了，是代码运行的报错，而不是测试期望结果的报错，顺着报错信息，我们可以找到报错原因。

在 `core/xhr.ts` 中，执行到 `processHeaders` 中的 `Object.keys(headers).forEach` 代码报错，因为我们在拦截器对请求配置做了修改，导致 `headers` 为空，所以报错。

于是我们在解构赋值 `headers` 的时候，给它添加默认值即可。

    const {
      // ...
      headers = {}
    } = config

1
2
3
4

再次运行测试，发现全部测试通过。

至此，我们完成了 `ts-axios` 库对拦截器模块的单元测试，下节课我们来测试 `mergeConfig` 模块的业务逻辑。

编辑
(opens new window)
#TypeScript
上次更新: 2022/12/14, 19:36:42
Axios 实例模块单元测试
mergeConfig 模块单元测试

← Axios 实例模块单元测试 mergeConfig 模块单元测试→

最近更新

  01
Git修改分支名
08-11

  02
CSS给table的tbody添加滚动条
06-29

  03
我做了一个手写春联小网页，祝大家虎年暴富 原创
01-28

更多文章>

Copyright © 2016-2022 Hesb | MIT License

- 跟随系统
- 浅色模式
- 深色模式
- 阅读模式