Awesome

Tasty Lens

Preassembled tasty TestTrees with sensible defaults for the validation of:

• Lens
• Setter
• Traversal
• Iso
• Prism

Although these tests offer weaker guarantees compared to manually proving the laws through equational reasoning, they can still be useful for regression testing where you don't want to manually proof every time you make a slight change that could affect the laws.

It uses smallcheck-lens under the hood. If you don't find any functions to create the TestTrees you are looking for, you may want to use the smallcheck-lens package directly. In such case you can still check this package as a reference to implement your own smallcheck-lens TestTrees.

Check the tests in this package for usage examples.

Contact

Contributions and bug reports are welcome!

Please feel free to contact jdnavarro on the #haskell IRC channel on irc.freenode.net.