FsCheck is a tool for testing .NET programs automatically. You provide a specification of the program, in the form of properties which functions, methods or objects should satisfy, and FsCheck then tests that the properties hold in a large number of randomly generated cases. Such properties are actually a testable specification of your program. Properties are written in F#, C# or VB. FsCheck helps you to define properties, observe the distribution of test data, and define test data generators. Crucially, when a property fails, FsCheck automatically displays a minimal counter example.
FsCheck is a tool for testing .NET programs automatically. The programmer provides a specification of the program in the form of properties which functions, methods or objects should satisfy, and FsCheck then tests that the properties hold in a large number of randomly generated cases.
Install via NuGet:
dotnet add package FsCheck
Define a property as a function that returns bool:
open FsCheck
let revRevIsOrig (xs:list<int>) = List.rev(List.rev xs) = xs
Check.Quick revRevIsOrig
When a property fails, FsCheck automatically displays a minimal counter-example and shrinks it to find the simplest failure case.
For comprehensive documentation, visit https://fscheck.github.io/FsCheck/
FsCheck is licensed under the BSD 3-Clause license.
FAQs
FsCheck is a tool for testing .NET programs automatically. You provide a specification of the program, in the form of properties which functions, methods or objects should satisfy, and FsCheck then tests that the properties hold in a large number of randomly generated cases. Such properties are actually a testable specification of your program. Properties are written in F#, C# or VB. FsCheck helps you to define properties, observe the distribution of test data, and define test data generators. Crucially, when a property fails, FsCheck automatically displays a minimal counter example.
We found that FsCheck demonstrated a healthy version release cadence and project activity because the last version was released less than a year ago. It has 1 open source maintainer collaborating on the project.
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