Jest compatibility API: replaceProperty

[trivikr]

Clear and concise description of the problem

Jest introduced API replaceProperty in v29.4.0

• PR: [Feature]: Replace property value in tests jestjs/jest#13465
• Docs: https://jestjs.io/docs/jest-object#jestreplacepropertyobject-propertykey-value

This API is also available in sinon
https://sinonjs.org/releases/v14/sandbox/#sandboxreplaceobject-property-replacement

Example code tested with jest@29.4.2:

test("replaceProperty", () => {
  expect(process.env.TEST_ENV_KEY).toBeUndefined();
  jest.replaceProperty(process, 'env', { TEST_ENV_KEY: "test" });  
  expect(process.env.TEST_ENV_KEY).toBe("test");
  jest.restoreAllMocks();
  expect(process.env.TEST_ENV_KEY).toBeUndefined();
});

Suggested solution

Add vi.replaceProprety API

Alternative

No response

Additional context

No response

Validations

• Follow our Code of Conduct
• Read the Contributing Guidelines.
• Read the docs.
• Check that there isn't already an issue that request the same feature to avoid creating a duplicate.

[mysteryven]

Thanks for your mention, I'd like to take this when it adds the label.

[trivikr]

@sheremet-va Would replaceProperty API be helpful to vitest users?

If yes, can you add enhancement and/or pr welcome labels?
@mysteryven is interested in implementing it.

[sheremet-va]

I do like the API, but I don't like that restoreAllMocks affects it. We have a similar API with stubs for a global object (stubGlobal) and env (stubEnv) already. Do we need more?

[trivikr]

The APIs vi.stubGlobal and vi.stubEnv are better fit for this requirement.

I verified that those work:

test("stubEnv", () => {
  expect(process.env.TEST_ENV_KEY).toBeUndefined();
  vi.stubEnv("TEST_ENV_KEY", "test");
  expect(process.env.TEST_ENV_KEY).toBe("test");
  vi.unstubAllEnvs();
  expect(process.env.TEST_ENV_KEY).toBeUndefined();
});

test("stubGlobal", () => {
  expect(global.innerWidth).toBeUndefined();

  const mockInnerWidth = 100;
  vi.stubGlobal("innerWidth", 100);
  expect(innerWidth).toBe(mockInnerWidth);
  expect(global.innerWidth).toBe(mockInnerWidth);

  vi.unstubAllGlobals();
  expect(global.innerWidth).toBeUndefined();
});

[trivikr]

@mysteryven As part of this request, can you add documentation in migration guide calling out the difference with Jest?

[mysteryven]

@mysteryven As part of this request, can you add documentation in migration guide calling out the difference with Jest?

Of course, I will add it.

[trivikr]

The vitest-codemod will transform replaceProperty with stubEnv for process.env

trivikr/vitest-codemod#126