LeanCheck support for test-framework.
|LTS Haskell 18.13:||0.0.4|
|Stackage Nightly 2021-10-13:||0.0.4|
|Latest on Hackage:||0.0.4|
Module documentation for 0.0.4
test-framework-leancheck: LeanCheck support for test-framework
$ cabal install test-framework-leancheck
Here’s how your
test.hs might look like:
import Test.Framework import Test.Framework.Providers.LeanCheck as LC import Data.List main :: IO () main = defaultMain tests tests :: [Test] tests = [ LC.testProperty "sort . sort == sort" $ \xs -> sort (sort xs :: [Int]) == sort xs , LC.testProperty "sort == id" -- not really, should fail $ \xs -> sort (xs :: [Int]) == xs ]
And here is the output for the above program:
$ ./eg/test sort . sort == sort: [OK, passed 100 tests.] sort == id: [Failed] *** Failed! Falsifiable (after 7 tests): [1,0] Properties Total Passed 1 1 Failed 1 1 Total 2 2
--maximum-generated-tests to configure
the maximum number of tests for each property.
$ ./eg/test -a5 sort . sort == sort: [OK, passed 5 tests.] sort == id: [OK, passed 5 tests.] Properties Total Passed 2 2 Failed 0 0 Total 2 2
Since LeanCheck is enumerative, you may want to increase the default number of tests (100). Arbitrary rule of thumb:
- between 200 to 500 on a developer machine;
- between 1000 and 5000 on the CI.
Your mileage may vary.