-
Notifications
You must be signed in to change notification settings - Fork 0
/
Emitter.spec.js
290 lines (222 loc) · 10.6 KB
/
Emitter.spec.js
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
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
import { jest, expect, test } from '@jest/globals'
import Emitter from '../src/Emitter.js'
const INVALID_INPUT_TYPES = [
'',
{},
[],
NaN,
false,
null
]
describe('Constructor', () => {
test('Given that we want to instantiate the object with an invalid argument', () => {
INVALID_INPUT_TYPES.concat(-1, () => {}).forEach(input => expect(() => new Emitter(input)).toThrowError())
})
test('Given that we want to instantiate the object with a valid argument', () => {
expect(() => new Emitter()).not.toThrow()
expect(new Emitter().maxListeners).toBe(10)
const emitter = new Emitter(15)
expect(emitter.maxListeners).toBe(15)
emitter.maxListeners = 5
expect(emitter.maxListeners).toBe(5)
emitter.maxListeners = undefined
expect(emitter.maxListeners).toBe(10)
expect(emitter.eventNames.length).toBe(0)
})
})
describe('Methods', () => {
test('Given that we want to append a listener', () => {
const emitter = new Emitter()
const eventName = 'test'
const listener = () => {}
INVALID_INPUT_TYPES.concat(0, Infinity, () => {}, undefined).forEach(input => {
expect(() => emitter.addListener(input, listener)).toThrowError(new TypeError('Invalid eventName'))
expect(() => emitter.on(input, listener)).toThrowError(new TypeError('Invalid eventName'))
})
INVALID_INPUT_TYPES.concat(0, Infinity, undefined).forEach(input => {
expect(() => emitter.addListener(eventName, input)).toThrowError(new TypeError('Invalid listener'))
expect(() => emitter.on(eventName, input)).toThrowError(new TypeError('Invalid listener'))
})
expect(emitter
.addListener(eventName, listener)
.on(eventName, listener)).toBeInstanceOf(Emitter)
expect(emitter.eventNames).toEqual([eventName])
expect(() => {
emitter.maxListeners = 1
}).toThrowError(new Error('Memory leak detected'))
emitter.maxListeners = 2
expect(() => emitter.addListener(eventName, listener)).toThrowError(new Error('Memory leak detected'))
})
test('Given that we want to get the raw listeners', () => {
const emitter = new Emitter()
const eventName = 'test'
const listener1 = () => {}
const listener2 = () => {}
INVALID_INPUT_TYPES.concat(0, Infinity, () => {}, undefined).forEach(input => {
expect(() => emitter.rawListeners(input)).toThrowError(new TypeError('Invalid eventName'))
})
expect(emitter.rawListeners(eventName)).toEqual([])
expect(emitter
.on(eventName, listener1)
.on(eventName, listener2)).toBeInstanceOf(Emitter)
expect(emitter.rawListeners(eventName)).toEqual([listener1, listener2])
})
test('Given that we want to prepend a listener', () => {
const emitter = new Emitter()
const eventName = 'test'
const listener1 = () => {}
const listener2 = () => {}
INVALID_INPUT_TYPES.concat(0, Infinity, () => {}, undefined).forEach(input => {
expect(() => emitter.prependListener(input, listener1)).toThrowError(new TypeError('Invalid eventName'))
})
INVALID_INPUT_TYPES.concat(0, Infinity, undefined).forEach(input => {
expect(() => emitter.prependListener(eventName, input)).toThrowError(new TypeError('Invalid listener'))
})
expect(emitter
.on(eventName, listener1)
.prependListener(eventName, listener2)).toBeInstanceOf(Emitter)
expect(emitter.rawListeners(eventName)).toEqual([listener2, listener1])
})
test('Given that we want to emit an event', async () => {
const emitter = new Emitter()
const eventName = 'test'
const listener = jest.fn()
emitter.on(eventName, listener)
for (const input of INVALID_INPUT_TYPES.concat(0, Infinity, () => {}, undefined)) {
await expect(() => emitter.emit(input, 'arg')).rejects.toThrowError(new TypeError('Invalid eventName'))
}
await expect(emitter.emit('foo', 'bar')).resolves.toBeFalsy()
expect(listener).not.toHaveBeenCalled()
await expect(emitter.emit(eventName, 'arg')).resolves.toBeTruthy()
expect(listener).toHaveBeenCalled()
})
test('Given that we want to count the listeners', async () => {
const emitter = new Emitter()
const eventName = 'test'
const listener1 = () => {}
const listener2 = () => {}
INVALID_INPUT_TYPES.concat(0, Infinity, () => {}, undefined).forEach(input => {
expect(() => emitter.listenerCount(input, listener1)).toThrowError(new TypeError('Invalid eventName'))
})
INVALID_INPUT_TYPES.concat(0, Infinity).forEach(input => {
expect(() => emitter.listenerCount(eventName, input)).toThrowError(new TypeError('Invalid listener'))
})
expect(emitter
.on(eventName, listener1)
.on(eventName, listener2)).toBeInstanceOf(Emitter)
expect(emitter.listenerCount(eventName)).toBe(2)
expect(emitter.listenerCount(eventName, listener1)).toBe(1)
expect(emitter.listenerCount(eventName, listener2)).toBe(1)
})
test('Given that we want to push a once listener', async () => {
const emitter = new Emitter()
const eventName = 'test'
const listener1 = () => {}
const listener2 = () => {}
const listener3 = () => {}
INVALID_INPUT_TYPES.concat(0, Infinity, () => {}, undefined).forEach(input => {
expect(() => emitter.once(input, listener1)).toThrowError(new TypeError('Invalid eventName'))
expect(() => emitter.prependOnceListener(input, listener1)).toThrowError(new TypeError('Invalid eventName'))
})
INVALID_INPUT_TYPES.concat(0, Infinity, undefined).forEach(input => {
expect(() => emitter.once(eventName, input)).toThrowError(new TypeError('Invalid listener'))
expect(() => emitter.prependOnceListener(eventName, input)).toThrowError(new TypeError('Invalid listener'))
})
expect(emitter
.on(eventName, listener1)
.once(eventName, listener2)
.prependOnceListener(eventName, listener3)).toBeInstanceOf(Emitter)
expect(emitter.listenerCount(eventName)).toBe(3)
expect(emitter.rawListeners(eventName)).toEqual([listener3, listener1, listener2])
await expect(emitter.emit(eventName, 'arg')).resolves.toBeTruthy()
expect(emitter.listenerCount(eventName)).toBe(1)
expect(emitter.listenerCount(eventName, listener1)).toBe(1)
})
test('Given that we want to get the listener count', () => {
const emitter = new Emitter()
const eventName = 'test'
const listener1 = () => {}
const listener2 = () => {}
expect(emitter
.addListener(eventName, listener1)
.on(eventName, listener1)
.addListener(eventName, listener2)).toBeInstanceOf(Emitter)
expect(emitter.eventNames).toEqual([eventName])
expect(emitter.listenerCount(eventName)).toBe(3)
expect(emitter.listenerCount(eventName, listener1)).toBe(2)
expect(emitter.listenerCount(eventName, listener2)).toBe(1)
})
test('Given that we want to remove listener', () => {
const emitter = new Emitter()
const eventName = 'test'
const listener1 = () => {}
const listener2 = () => {}
INVALID_INPUT_TYPES.concat(0, Infinity, () => {}, undefined).forEach(input => {
expect(() => emitter.removeListener(input, listener1)).toThrowError(new TypeError('Invalid eventName'))
expect(() => emitter.off(input, listener1)).toThrowError(new TypeError('Invalid eventName'))
})
INVALID_INPUT_TYPES.concat(0, Infinity, undefined).forEach(input => {
expect(() => emitter.removeListener(eventName, input)).toThrowError(new TypeError('Invalid listener'))
expect(() => emitter.off(eventName, input)).toThrowError(new TypeError('Invalid listener'))
})
expect(emitter
.on(eventName, listener1)
.on(eventName, listener2)).toBeInstanceOf(Emitter)
expect(emitter.listenerCount(eventName)).toBe(2)
expect(emitter.removeListener(eventName, () => {})).toBeInstanceOf(Emitter)
expect(emitter.removeListener(eventName, listener1)).toBeInstanceOf(Emitter)
expect(emitter.listenerCount(eventName, listener1)).toBe(0)
expect(emitter.listenerCount(eventName, listener2)).toBe(1)
expect(emitter.on(eventName, listener1)).toBeInstanceOf(Emitter)
expect(emitter.listenerCount(eventName)).toBe(2)
expect(emitter.off(eventName, listener1)).toBeInstanceOf(Emitter)
expect(emitter.listenerCount(eventName, listener1)).toBe(0)
expect(emitter.listenerCount(eventName, listener2)).toBe(1)
expect(emitter.off(eventName, listener2)).toBeInstanceOf(Emitter)
expect(emitter.listenerCount(eventName)).toBe(0)
expect(emitter.removeListener(eventName, listener1)).toBeInstanceOf(Emitter)
})
test('Given that we want to remove all listeners', () => {
const emitter = new Emitter()
const eventName1 = 'test1'
const eventName2 = 'test2'
const listener1 = () => {}
const listener2 = () => {}
INVALID_INPUT_TYPES.concat(0, Infinity, () => {}).forEach(input => {
expect(() => emitter.removeAllListeners(input)).toThrowError(new TypeError('Invalid eventName'))
})
expect(emitter
.on(eventName1, listener1)
.on(eventName1, listener2)).toBeInstanceOf(Emitter)
expect(emitter
.on(eventName2, listener1)
.on(eventName2, listener2)).toBeInstanceOf(Emitter)
expect(emitter.listenerCount(eventName1)).toBe(2)
expect(emitter.listenerCount(eventName2)).toBe(2)
expect(emitter.removeAllListeners(eventName1)).toBeInstanceOf(Emitter)
expect(emitter.listenerCount(eventName1)).toBe(0)
expect(emitter.listenerCount(eventName2)).toBe(2)
expect(emitter.removeAllListeners()).toBeInstanceOf(Emitter)
expect(emitter.listenerCount(eventName2)).toBe(0)
expect(emitter.eventNames.length).toBe(0)
expect(emitter.removeAllListeners(eventName1)).toBeInstanceOf(Emitter)
})
test('Given that we want to get the listeners', () => {
const emitter = new Emitter()
const eventName = 'test'
const listener1 = () => {}
const listener2 = () => {}
const listener3 = () => {}
const listener4 = () => {}
INVALID_INPUT_TYPES.concat(0, Infinity, () => {}, undefined).forEach(input => {
expect(() => emitter.listeners(input)).toThrowError(new TypeError('Invalid eventName'))
})
expect(emitter.listeners(eventName)).toEqual([])
expect(emitter
.on(eventName, listener1)
.once(eventName, listener2)
.prependOnceListener(eventName, listener3)
.on(eventName, listener4)).toBeInstanceOf(Emitter)
expect(emitter.listeners(eventName)).toEqual([listener1, listener4])
})
})