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fp-testing

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bun add -d @stopcock/fp-testing

The package has no runtime dependencies. Its structural interfaces accept Stopcock instances and compatible user-defined values without adapters.

import { assertLaws, checkMonoidLaws } from '@stopcock/fp-testing/laws'
import * as Monoid from '@stopcock/fp/monoid'


assertLaws(checkMonoidLaws(Monoid.numberSum, { equals: Object.is }, [-1, 0, 1, Number.NaN]))

@stopcock/fp-testing/laws checks Eq, Hash, Ord, Semigroup, Monoid, Group, Lens, and Iso laws with bounded deterministic reports. @stopcock/fp-testing/data provides stable Option, Result, tuple, array, number, and string cases. @stopcock/fp-testing/iterable provides tracked and throwing iterables so laziness, pull counts, and iterator cleanup are explicit test assertions.