FsCheck vs QuickCheck

FsCheck checks properties of.NET programs against randomly generated cases. Developers can express properties in F#, C# or VB, then run them with the built-in runner from an interactive session, a command-line program or a test framework. Integrations are documented for xUnit.net and NUnit, with user-created integrations for Expecto, Fuchu, AutoFixture and MSTest. When a property fails, FsCheck shrinks the input and shows a minimal counterexample. Developers can also define custom generators and shrinkers and group them in Arbitrary instances. The library supports parameterized cases and parallel execution, and its packages and NUnit and xUnit.NET plugins are available from NuGet. FsCheck is free: its listed plan is free, with a BSD license permitting commercial and non-commercial modification and redistribution. It runs on Linux, macOS and Windows. The project maintains version 3.x, but its documentation covers 2.x and is described as out of date and incomplete. Its model-based testing API is experimental and exempt from semantic-versioning guarantees.

QuickCheck is a free Haskell library for testing program properties against randomly generated cases. Developers write specifications with QuickCheck combinators and can use combinators to define test-data generators and inspect generated-data distributions. It supports stateful testing, reproducible failures and shrinking failing cases. Monadic property testing is provided through the Test.QuickCheck.Monadic module. The package README describes adding QuickCheck to project dependencies for use in tests or a REPL. A companion package, quickcheck-instances, supplies instances for types in Haskell Platform packages, with additional dependencies. QuickCheck is licensed under BSD-3-Clause and lists dependencies including base, containers, random, splitmix, template-haskell and transformers. Hackage reports it tested with GHC versions from 8.10 up to but not including 9.15, as well as Hugs. A make-hugs script creates a Hugs-compatible version and may be useful for other non-GHC implementations. Hackage lists QuickCheck-2.18.0.0 as a downloadable Cabal source package. The listed package plan costs nothing.