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no-tautological-expect

Disallow supported assertions known to pass from literals or immutable scalar setup.

tautologicalComparisontautologicalMatcher Rule source Tests Catalog JSON

Why

An assertion determined entirely by literals does not observe the code under test and can keep passing after that code is removed.

Fix

Assert on a value produced by the behavior under test, or remove the assertion.

Examples

Before — flagged Do not compare identical literals

src/add.test.ts

it("works", () => {
  expect(true).toBe(true);
});

After — preferred Assert on a produced value

src/add.test.ts

it("adds", () => {
  expect(add(1, 1)).toBe(2);
});

Before — flagged A const setup assertion never observes the application

src/service.test.ts

it("works", () => {
  const status = "ok";
  expect(status).toBe("ok");
});

After — preferred A runtime scalar result remains a valid observation

src/service.test.ts

it("works", () => {
  const status = serviceStatus();
  expect(status).toBe("ok");
});