mock_fetch.ts

function mockFetch(config: { data?: any; headers?: any; json?: boolean; blob?: boolean; text?: boolean | string; status?: any; statusText?: string; error?: object | string; delay?: boolean }) {
        const { data, headers, json = false, blob = false, text = false, status = 200, statusText = 'Success', error = '', delay = false } = config;
        if (status >= 400) {
            return jest.fn().mockImplementation(() => Promise.reject(error));
        }
        const local_headers = { 'Content-type': 'application/json' };
        const res = new window.Response(data, {
            status,
            statusText,
            headers: headers && Object.keys(headers).length === 0 ? local_headers : headers,
        });

        if (blob) {
            res.blob = () => Promise.resolve({} as any);
        }
        if (json) {
            res.json = () => Promise.resolve(data);
        }
        if (text) {
            res.text = () => Promise.resolve(JSON.stringify(Array.isArray(data) ? data[0] : data));
        }
        if (delay) {
            return jest.fn().mockImplementation(
                () =>
                    new Promise((result) =>
                        setTimeout(() => {
                            result(res);
                        }, 200)
                    )
            );
        } else {
            return jest.fn().mockImplementation(() => Promise.resolve(res));
        }
    };