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mockFetch function for jest
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| export type FetchConfig = RequestInit & { | |
| postman?: boolean; | |
| method?: keyof typeof HTTPMethods; | |
| body?: any; | |
| root: string; | |
| path?: string; | |
| params?: Record<string, any>; | |
| }; | |
| export interface Global { | |
| document: Document; | |
| window: Window; | |
| fetch: (url: string, config: any) => Promise<any>; | |
| } | |
| declare const global: Global; | |
| type OnFetch = (request: RequestInit) => Promise<any>; | |
| export const unmockFetch = () => { | |
| // @ts-ignore | |
| if (global.fetch && global.fetch.mockRestore) global.fetch.mockRestore(); | |
| }; | |
| export const mockFetch = (onFetch: OnFetch) => { | |
| unmockFetch(); | |
| const mockFetch = async (url: string, config: FetchConfig) => { | |
| let parsedBody; | |
| try { | |
| parsedBody = JSON.parse(config.body); | |
| } catch (e) {} | |
| try { | |
| const json = await onFetch({ | |
| ...new Request(url, config), | |
| // a slightly hacky convenience | |
| // to offer access to the body object, if it exists | |
| body: parsedBody | |
| }); | |
| return Promise.resolve({ | |
| ok: true, | |
| json() { | |
| return json; | |
| } | |
| }); | |
| } catch (e) { | |
| return Promise.resolve({ | |
| ok: false, | |
| json() { | |
| return e; | |
| } | |
| }); | |
| } | |
| }; | |
| jest.spyOn(global, "fetch").mockImplementation(mockFetch); | |
| }; |
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