jest/no-restricted-jest-methods

Some teams agree not to use parts of the jest object, like module mocks, fake timers or spies. This rule reports the methods you list, with your own message if you give one, so the agreement doesn't depend on review.

The rule does nothing until you give it a list.

Configure#

Off by default. To turn it on:

[lint.rules]
"jest/no-restricted-jest-methods" = "error" # or "warn"

Examples#

These examples restrict advanceTimersByTime and spyOn.

import { expect, jest, test } from "@jest/globals";

test("retries after a second", () => {
  const send = jest.spyOn(mailer, "send");
  retry(send);
  jest.advanceTimersByTime(1000);
  expect(send).toHaveBeenCalledTimes(2);
});

import { expect, jest, test } from "@jest/globals";

test("retries once", () => {
  const send = jest.fn();
  retry(send);
  expect(send).toHaveBeenCalledTimes(2);
});

Options#

The rule takes one object. Each key is a method name. The value is the message to report, or null for the default message: Use of `spyOn` is not allowed.

{
  "plugins": ["jest"],
  "rules": {
    "jest/no-restricted-jest-methods": [
      "error",
      {
        "advanceTimersByTime": null,
        "spyOn": "Pass the dependency in instead of spying on it"
      }
    ]
  }
}