stubEndpointThrow

Forces endpoint.request to reject with a value you provide (not necessarily an HttpResponse). error can be a value or a function (sync/async) that returns the rejection.

• Default: mockImplementationOnce — only the first call throws, then the real request runs again.
• persistent: true: every call throws (pass it in the third argument together with any other options).

Optional abortSignal goes in that same options object, e.g. { abortSignal: signal } from Vitest’s test context — the spy is restored when the test is cancelled. You still call spy.mockRestore() yourself in a normal teardown; that stays safe.

Example — one failure, then real behavior:

const spy = stubEndpointThrow(deleteItem, new Error('offline'));
await expect(deleteItem.request({ id: 1 })).rejects.toThrow('offline');
await deleteItem.request({ id: 2 }); // uses real client again
spy.mockRestore();

Example — every call throws:

const spy = stubEndpointThrow(deleteItem, () => new Error('forbidden'), {
  persistent: true,
});
await expect(deleteItem.request({ id: 1 })).rejects.toThrow('forbidden');
await expect(deleteItem.request({ id: 2 })).rejects.toThrow('forbidden');
spy.mockRestore();