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copied!<p>Here's a fragment of the <code>.cabal</code> file I used for one of my recent <a href="https://github.com/scvalex/ltc/blob/master/ltc.cabal">libraries</a>.</p> <pre><code>... Library Build-depends: base >= 4 && < 5, bytestring, directory, filepath, hslogger, SHA, zlib Ghc-options: -Wall Exposed-modules: Ltc.Store Test-suite reference Hs-Source-Dirs: Test, . Main-Is: ReferenceProps.hs Type: exitcode-stdio-1.0 Build-Depends: base >= 4 && < 5, bytestring, directory, filepath, hslogger, SHA, zlib Ghc-Options: -Wall Build-Depends: test-framework, test-framework-hunit, test-framework-quickcheck2, HUnit, QuickCheck </code></pre> <p>As we can see the cabal file defines a library and a testsuite. The library defines the modules it exports, the packages it depends on, and sets some custom GHC options.</p> <p>We can easily build and package the library for distribution with:</p> <pre><code>% cabal configure % cabal build % cabal sdist </code></pre> <p>The testsuite looks a lot like the the library: first off, it has the same dependencies as the library (see the first <code>Build-Depends</code> line), and it then adds some extra test dependencies (see the second <code>Build-Depends</code> line). The testsuite here is a combination of HUnit and QuickCheck tests, and it uses <a href="http://hackage.haskell.org/package/test-framework">Test-Framework</a> as the runner. The <em>test</em> proper is <code>Test/ReferenceProps.hs</code>. It's a <code>exitcode-stdio</code> type test. This means that cabal will say that the tests pass if <code>ReferenceProps</code> exits with code 0. Otherwise, it will say the tests failed.</p> <p>The testsuite looks like <a href="https://github.com/scvalex/ltc/blob/master/Test/ReferenceProps.hs">this</a> (but, here, we're going to use some simple tests for list reversals):</p> <pre><code>import Data.Monoid import Test.Framework import Test.Framework.Providers.HUnit import Test.Framework.Providers.QuickCheck2 import Test.HUnit import Test.QuickCheck main :: IO () main = defaultMainWithOpts [ testCase "rev" testRev , testProperty "listRevRevId" propListRevRevId ] mempty testRev :: Assertion testRev = reverse [1, 2, 3] @?= [3, 2, 1] propListRevRevId :: [Int] -> Property propListRevRevId xs = not (null xs) ==> reverse (reverse xs) == xs </code></pre> <p>The <code>main</code> is just a harness. You can also set various options for <code>test-framework</code> by replacing the <code>mempty</code>. The function <code>testRev</code> is a HUnit test, and <code>propListRevRevId</code> is a QuickCheck test; see the <a href="http://hackage.haskell.org/package/HUnit">relevant</a> <a href="http://hackage.haskell.org/package/QuickCheck">docs</a> on how to write these.</p> <p>Finally, we can run the tests:</p> <pre><code>% cabal configure --enable-tests % cabal test </code></pre>

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