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copied!<blockquote> <p>[my program] scans the declarations for variable names that start prop_, and builds a test suite containing them. Is there some other pure Haskell way I could do this instead, without directly munging source files?</p> </blockquote> <p>Yes, there is! Using <a href="http://hackage.haskell.org/packages/archive/language-haskell-extract/0.2.1/doc/html/Language-Haskell-Extract.html" rel="nofollow">the <code>language-haskell-extract</code> package</a>.</p> <pre><code>{-# LANGUAGE TemplateHaskell #-} import Language.Haskell.Extract import Test.QuickCheck prop_foo xs = reverse (reverse xs) == (xs :: [Int]) prop_bar = 2 + 2 == 4 properties = $(functionExtractorMap "^prop_" [|\name prop -> putStrLn name >> quickCheck prop|]) main = sequence_ properties </code></pre> <p>Running this, we get:</p> <pre><code>prop_foo +++ OK, passed 100 tests. prop_bar +++ OK, passed 100 tests. </code></pre> <hr> <p>However, before you go reinventing the wheel I would also recommend you take a look at <a href="http://hackage.haskell.org/package/test-framework-th" rel="nofollow">the <code>test-framework-th</code> package</a>, which does pretty much exactly this, but also supports HUnit and has a nice test runner (with colors!).</p> <pre><code>{-# LANGUAGE TemplateHaskell #-} import Test.Framework.Providers.HUnit import Test.Framework.Providers.QuickCheck2 import Test.Framework.TH import Test.HUnit import Test.QuickCheck prop_bar = 1+1 == 2 case_foo = 2+2 @?= 4 main = $(defaultMainGenerator) </code></pre> <p>Output:</p> <pre><code>Main: bar: [OK, passed 100 tests] foo: [OK] Properties Test Cases Total Passed 1 1 2 Failed 0 0 0 Total 1 1 2 </code></pre> <p>There's also a <code>testGroupGenerator</code> which is useful if you want to combine tests from multiple files.</p>

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