src/Assertions.hs

   1 -- | The Assertions module contains assertions for use in HUnit
   2 --   tests. They primarily fill the need for an equality test that
   3 --   works with floating point numbers.
   4 module Assertions
   5 where
   6
   7 import Control.Monad (unless)
   8 import Test.HUnit (Assertion,
   9                    assertBool,
  10                    assertFailure)
  11
  12 import Comparisons ((~=))
  13
  14
  15 -- | An HUnit assertion that wraps the almost_equals function. Stolen
  16 --   from the definition of 'assertEqual' in Test\/HUnit\/Base.hs.
  17 assertAlmostEqual :: String -> Double -> Double -> Assertion
  18 assertAlmostEqual preface expected actual =
  19   unless (actual ~= expected) (assertFailure msg)
  20     where msg = (if null preface then "" else preface ++ "\n") ++
  21                 "expected: " ++ show expected ++ "\n but got: " ++ show actual
  22
  23
  24
  25 -- | It's asinine that this doesn't exist already.
  26 assertTrue :: String -> Bool -> Assertion
  27 assertTrue = assertBool