⚠️ Archival notice

As of Jan 9 2023, this repository has been archived, and has been replaced by the liqwid-libs monorepo. Please use that instead.

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plutarch-quickcheck

Public discussion and assistance can be found on discord @ #liqwid-libs.

Issues and project-management-related information are tracked on Notion.

What is this?

A helper library to write Plutarch-oriented QuickCheck property tests. The interfaces plutarch-quickcheck provides are designed to look and feel like writting regular QuickCheck properties.

What exactly does this do for me?

QuickCheck's interactions with Plutarch can be non-obvious, and much of the built-in functionality it provides is not very useful for it. For example, Arbitrary typeclass that provide random values for properties cannot be used for defining arbitrary Plutarch values.

plutarch-quickcheck defines alternative interfaces like PArbitrary, providing interfaces that feels like using normal QuickCheck. As demonstrated below, one can easily define a property in Plutarch function and use it directly.

additionCommutative :: Term s (PInteger :--> PInteger :--> PBool)
additionCommutative = plam $ \x y -> x + y #== y + x

quickCheck $ fromPFun additionCommutative -- Magic!
-- +++ OK, passed 100 tests.

The library also provides other utilities such as the generation of arbitrary Plutarch functions and defining properties for Plutarch functions verified by the equivalent Haskell definition. Currently, only functions with a single arguement are supported.

pfunctionGeneration :: Term s (PFun PInteger PInteger :--> PBool)
pfunctionGeneration = plam $ \(PFn (f :: Term s (PInteger :--> PInteger))) -> ...

reverseProperty :: Property
reverseProperty = haskEquiv' reverse (preverse @PBuiltinList)

How do I use this?

We provide extensive documentation in the public modules for those who are already comfortable with tasty-quickcheck and property testing in general; for those who are not, or those who prefer to learn from examples, we provide three executable examples:

• examples/reverse-tests, which demonstrates how to define a property using a Haskell definition for intended behavior.
• examples/zip-tests, which demonstrates how to use fromPFun to define a Plutarch property.

Users new to the library can read the examples as code, as well as execute the tests with cabal test to see what they do.

We also have a Notion article describing good practices for use of this library, as well as QuickCheck and tasty-quickcheck in general. We recommend reading this even for experienced QuickCheck hands, as there are a lot of useful, and less-known, bits of information there.

To integrate this with your project, use Nix. We work against the master branch of Plutarch, so you will have to use it also. See the flake.nix file for more details.

Standards

The plutarch-quickcheck code base follows strict standards to increase consistency, to minimize the impact of legacy, to properly use automated tools, and more. The standards document can be found here.

What can I do with this?

plutarch-quickcheck is licensed under the Apache 2.0 license (SPDX code Apache-2.0); please see the LICENSE file for more details.