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Introduce `checkIO` as a runtime alternative to `check` for property-based
tests. While `check` runs during compilation with a fixed seed, `checkIO`
defers execution to runtime with configurable random seeds via
`cfg.randomSeed`.
Key changes:
- Add `isPassed` constructor to `Testable` for tests that pass without
formal proof (distinguishes SlimCheck successes from inconclusive results)
- Add `individualIO` constructor to `TestSeq` for deferred IO tests
- Add `TestSeq.runIO` to execute IO tests at runtime
- Update `lspecIO` and `lspecEachIO` to use the new IO runner
- Add comprehensive documentation for the framework
- Add `describe` and `context` as aliases for `group`, matching hspec's
naming conventions for better test organization and readability
- Add `Gen.frequency` combinator for weighted random generation,
allowing generators to be selected with specified probabilities
- Add examples demonstrating both features with property-based tests
arthurpaulino
approved these changes
Jan 20, 2026
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checkIOas a runtime alternative tocheckfor property-based tests. Whilecheckruns during compilation with a fixed seed,checkIOdefers execution to runtime with configurable random seeds viacfg.randomSeed.describeandcontextas aliases forgroup, matching hspec's naming conventions for better test organization and readabilityGen.frequencycombinator for weighted random generation, allowing generators to be selected with specified probabilities