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
import { StrictMode, useEffect, useRef } from 'react'import type { PropsWithChildren } from 'react'import { fireEvent, render, waitFor } from '@testing-library/react'import { atom, useAtom, useSetAtom } from 'jotai'import { getTestProvider } from './testUtils'
const Provider = getTestProvider()
const useCommitCount = () => {  const commitCountRef = useRef(1)  useEffect(() => {    commitCountRef.current += 1  })  return commitCountRef.current}
it('useSetAtom does not trigger rerender in component', async () => {  const countAtom = atom(0)
  const Displayer = () => {    const [count] = useAtom(countAtom)    const commits = useCommitCount()    return (      <div>        count: {count}, commits: {commits}      </div>    )  }
  const Updater = () => {    const setCount = useSetAtom(countAtom)    const commits = useCommitCount()    return (      <>        <button onClick={() => setCount((value) => value + 1)}>          increment        </button>        <div>updater commits: {commits}</div>      </>    )  }
  const Parent = () => {    return (      <>        <Displayer />        <Updater />      </>    )  }
  const { getByText } = render(    <>      <Provider>        <Parent />      </Provider>    </>  )
  await waitFor(() => {    getByText('count: 0, commits: 1')    getByText('updater commits: 1')  })  fireEvent.click(getByText('increment'))  await waitFor(() => {    getByText('count: 1, commits: 2')    getByText('updater commits: 1')  })  fireEvent.click(getByText('increment'))  await waitFor(() => {    getByText('count: 2, commits: 3')    getByText('updater commits: 1')  })  fireEvent.click(getByText('increment'))  await waitFor(() => {    getByText('count: 3, commits: 4')    getByText('updater commits: 1')  })})
it('useSetAtom with scope', async () => {  const scope = Symbol()  const countAtom = atom(0)
  const Displayer = () => {    const [count] = useAtom(countAtom, scope)    return <div>count: {count}</div>  }
  const Updater = () => {    const setCount = useSetAtom(countAtom, scope)    return (      <button onClick={() => setCount((value) => value + 1)}>increment</button>    )  }
  const Parent = () => {    return (      <>        <Displayer />        <Updater />      </>    )  }
  const { getByText } = render(    <StrictMode>      <Provider scope={scope}>        <Parent />      </Provider>    </StrictMode>  )
  await waitFor(() => {    getByText('count: 0')  })  fireEvent.click(getByText('increment'))  await waitFor(() => {    getByText('count: 1')  })})
it('useSetAtom with write without an argument', async () => {  const countAtom = atom(0)  const incrementCountAtom = atom(null, (get, set) =>    set(countAtom, get(countAtom) + 1)  )
  const Button = ({ cb, children }: PropsWithChildren<{ cb: () => void }>) => (    <button onClick={cb}>{children}</button>  )
  const Displayer = () => {    const [count] = useAtom(countAtom)    return <div>count: {count}</div>  }
  const Updater = () => {    const setCount = useSetAtom(incrementCountAtom)    return <Button cb={setCount}>increment</Button>  }
  const Parent = () => {    return (      <>        <Displayer />        <Updater />      </>    )  }  const { getByText } = render(    <StrictMode>      <Provider>        <Parent />      </Provider>    </StrictMode>  )
  await waitFor(() => {    getByText('count: 0')  })  fireEvent.click(getByText('increment'))  await waitFor(() => {    getByText('count: 1')  })})