const isNetworkError = require('./isNetworkError') describe('isNetworkError', () => { it('should return true if the specified xhr object contains a network error', () => { const xhrNetworkErrorMock = { readyState: 4, responseText: '', status: 0 } const xhrNetworkError2Mock = { readyState: 2, responseText: '', status: 300 } const xhrRegularErrorMock = { readyState: 4, responseText: 'Failed', status: 400 } const xhrNetworkSuccessMock = { readyState: 4, responseText: 'Success', status: 200 } expect(isNetworkError(xhrNetworkErrorMock)).toEqual(true) expect(isNetworkError(xhrNetworkError2Mock)).toEqual(true) expect(isNetworkError(xhrRegularErrorMock)).toEqual(false) expect(isNetworkError(xhrNetworkSuccessMock)).toEqual(false) }) })