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no-vacuous-numeric-assertions

Disallow numeric bound assertions with infinite thresholds.

Rule detailsโ€‹

Assertions such as expect(count).toBeLessThan(Infinity) and expect(count).toBeGreaterThan(-Infinity) do not establish a useful behavioral contract. They usually prove only that the value is being compared against an unreachable bound instead of the finite threshold the code is expected to meet.

Incorrectโ€‹

it("returns a count", () => {
    expect(loadCount()).toBeLessThan(Infinity);
});
it("returns a count", () => {
    expect(loadCount()).toBeGreaterThan(-Infinity);
});

Correctโ€‹

it("returns a bounded count", () => {
    expect(loadCount()).toBeLessThan(10);
});
it("returns at least one item", () => {
    expect(loadCount()).toBeGreaterThanOrEqual(1);
});

What this rule reportsโ€‹

This rule reports executable it(...) and test(...) callbacks where numeric bound matchers use Infinity or -Infinity as a vacuous threshold:

  • toBeLessThan(Infinity)
  • toBeLessThanOrEqual(Infinity)
  • toBeGreaterThan(-Infinity)
  • toBeGreaterThanOrEqual(-Infinity)
  • the equivalent negated impossible-bound forms

The rule does not flag exact toBe(Infinity) assertions because some tests may intentionally assert an explicit infinite value.

Optionsโ€‹

This rule has no options.

When not to use itโ€‹

Disable this rule only for tests that intentionally document numeric matcher semantics. Product tests should assert a finite boundary or exact expected value.

Rule catalog ID: R023