javascript - Jest: Better way to disable console inside unit tests

Question

I wonder if there is a better way to disable console errors inside a specific Jest test (i.e., restore the original console before/after each test).

Here is my current approach:

describe("Some description", () => {
  let consoleSpy;

  beforeEach(() => {
    if (typeof consoleSpy === "function") {
      consoleSpy.mockRestore();
    }
  });

  test("Some test that should not output errors to jest console", () => {
    expect.assertions(2);

    consoleSpy = jest.spyOn(console, "error").mockImplementation();

    // some function that uses console error
    expect(someFunction).toBe("X");
    expect(consoleSpy).toHaveBeenCalled();
  });

  test("Test that has console available", () => {
    // shows up during jest watch test, just as intended
    console.error("test");
  });
});

Is there a cleaner way of accomplishing the same thing? I would like to avoid spyOn, but mockRestore only seems to work with it.

Thanks!

Answer 1

For particular spec file, Andreas's is good enough. Below setup will suppress console.log statements for all test suites,

jest --silent

(or)

To customize warn, info and debug you can use below setup

__tests__/setup.js or jest-preload.js configured in setupFilesAfterEnv

global.console = {
  log: jest.fn(), // console.log are ignored in tests

  // Keep native behaviour for other methods, use those to print out things in your own tests, not `console.log`
  error: console.error,
  warn: console.warn,
  info: console.info,
  debug: console.debug,
};

jest.config.js

module.exports = {
    verbose: true,
    setupTestFrameworkScriptFile: "<rootDir>/__tests__/setup.js",
};

Jest v24.x Note: setupTestFrameworkScriptFile is deprecated in favor of setupFilesAfterEnv.

module.exports = {
    verbose: true,
    setupFilesAfterEnv: ["<rootDir>/__tests__/setup.js"],
};