hstest

Runs tests via QuickCheck1 and HUnit; like quickCheck-script but uses GHC api.

hstest looks through all Haskell source files in the current directory (by default), runs all properties via QuickCheck 1 (properties must have a name that starts prop_), and runs all tests via HUnit (tests must have a name that starts test_).

For example, suppose you have this Haskell source file called mysort.hs:

mySort xs = ... -- a function you wish to test (definition elided)

prop_lengthStaysTheSame xs = length xs == length (mySort xs)
prop_sumStaysTheSame xs = sum xs == sum (mySort xs)
prop_lowestElementAtStart, prop_highestElementAtEnd :: [Int] -> Bool
prop_lowestElementAtStart xs = not (null xs) ==> minimum xs == head (mySort xs)
prop_highestElementAtEnd xs = not (null xs) ==> maximum xs == last (mySort xs)

Then to check all these tests, you run

$ hstest
Failed prop_highestElementAtEnd:
 *  [-3,2,-2]
mysort.hs: Failed 1 property, passed 3 properties

Oops! Fix mySort and try again:

$ hstest
mysort.hs: Passed 4 properties