source: node_modules/@reduxjs/toolkit/src/query/tests/apiProvider.test.tsx@ a762898

import { configureStore } from '@reduxjs/toolkit'
import {
  ApiProvider,
  buildCreateApi,
  coreModule,
  createApi,
  reactHooksModule,
} from '@reduxjs/toolkit/query/react'
import { fireEvent, render, waitFor } from '@testing-library/react'
import { delay } from 'msw'
import * as React from 'react'
import type { ReactReduxContextValue } from 'react-redux'
import {
  Provider,
  createDispatchHook,
  createSelectorHook,
  createStoreHook,
} from 'react-redux'

const api = createApi({
  baseQuery: async (arg: any) => {
    await delay(150)
    return { data: arg?.body ? arg.body : null }
  },
  endpoints: (build) => ({
    getUser: build.query<any, number>({
      query: (arg) => arg,
    }),
    updateUser: build.mutation<any, { name: string }>({
      query: (update) => ({ body: update }),
    }),
  }),
})

afterEach(() => {
  vi.resetAllMocks()
})

describe('ApiProvider', () => {
  test('ApiProvider allows a user to make queries without a traditional Redux setup', async () => {
    function User() {
      const [value, setValue] = React.useState(0)

      const { isFetching } = api.endpoints.getUser.useQuery(1, {
        skip: value < 1,
      })

      return (
        <div>
          <div data-testid="isFetching">{String(isFetching)}</div>
          <button onClick={() => setValue((val) => val + 1)}>
            Increment value
          </button>
        </div>
      )
    }

    const { getByText, getByTestId } = render(
      <ApiProvider api={api}>
        <User />
      </ApiProvider>,
    )

    await waitFor(() =>
      expect(getByTestId('isFetching').textContent).toBe('false'),
    )
    fireEvent.click(getByText('Increment value'))
    await waitFor(() =>
      expect(getByTestId('isFetching').textContent).toBe('true'),
    )
    await waitFor(() =>
      expect(getByTestId('isFetching').textContent).toBe('false'),
    )
    fireEvent.click(getByText('Increment value'))
    // Being that nothing has changed in the args, this should never fire.
    expect(getByTestId('isFetching').textContent).toBe('false')
  })
  test('ApiProvider throws if nested inside a Redux context', () => {
    // Intentionally swallow the "unhandled error" message
    vi.spyOn(console, 'error').mockImplementation(() => {})
    expect(() =>
      render(
        <Provider store={configureStore({ reducer: () => null })}>
          <ApiProvider api={api}>child</ApiProvider>
        </Provider>,
      ),
    ).toThrowErrorMatchingInlineSnapshot(
      `[Error: Existing Redux context detected. If you already have a store set up, please use the traditional Redux setup.]`,
    )
  })
  test('ApiProvider allows a custom context', async () => {
    const customContext = React.createContext<ReactReduxContextValue | null>(
      null,
    )

    const createApiWithCustomContext = buildCreateApi(
      coreModule(),
      reactHooksModule({
        hooks: {
          useStore: createStoreHook(customContext),
          useSelector: createSelectorHook(customContext),
          useDispatch: createDispatchHook(customContext),
        },
      }),
    )

    const customApi = createApiWithCustomContext({
      baseQuery: async (arg: any) => {
        await delay(150)
        return { data: arg?.body ? arg.body : null }
      },
      endpoints: (build) => ({
        getUser: build.query<any, number>({
          query: (arg) => arg,
        }),
        updateUser: build.mutation<any, { name: string }>({
          query: (update) => ({ body: update }),
        }),
      }),
    })

    function User() {
      const [value, setValue] = React.useState(0)

      const { isFetching } = customApi.endpoints.getUser.useQuery(1, {
        skip: value < 1,
      })

      return (
        <div>
          <div data-testid="isFetching">{String(isFetching)}</div>
          <button onClick={() => setValue((val) => val + 1)}>
            Increment value
          </button>
        </div>
      )
    }

    const { getByText, getByTestId } = render(
      <ApiProvider api={customApi} context={customContext}>
        <User />
      </ApiProvider>,
    )

    await waitFor(() =>
      expect(getByTestId('isFetching').textContent).toBe('false'),
    )
    fireEvent.click(getByText('Increment value'))
    await waitFor(() =>
      expect(getByTestId('isFetching').textContent).toBe('true'),
    )
    await waitFor(() =>
      expect(getByTestId('isFetching').textContent).toBe('false'),
    )
    fireEvent.click(getByText('Increment value'))
    // Being that nothing has changed in the args, this should never fire.
    expect(getByTestId('isFetching').textContent).toBe('false')

    // won't throw if nested, because context is different
    expect(() =>
      render(
        <Provider store={configureStore({ reducer: () => null })}>
          <ApiProvider api={customApi} context={customContext}>
            child
          </ApiProvider>
        </Provider>,
      ),
    ).not.toThrow()
  })
})