如何在 Stack 中使用 HUnit

How to use HUnit in Stack

我有一个堆栈项目 stapro 和一个文件 app/Main.hs

module Main where

import Lib

main = putStrLn "This is main" 

foo::Int ->Int
foo = (+1)

和一个文件test/Spec.hs

module Spec where

import Test.HUnit
import Main (foo)

main :: IO ()
main = putStrLn "Test suite not yet implemented"

testFoo :: Test
testFoo = TestCase $ assertEqual "Should return 2" 2 (foo 1)

但是当我尝试执行测试时

$ stack test
While constructing the BuildPlan the following exceptions were encountered:

--  While attempting to add dependency,
    Could not find package Main in known packages

--  Failure when adding dependencies:    
      Main: needed (-any), stack configuration has no specified version
    needed for package stapro-0.1.0.0

我的 .cabal 文件是

name:                stapro
version:             0.1.0.0
...
build-type:          Simple
-- extra-source-files:
cabal-version:       >=1.10

library
  hs-source-dirs:      src
  exposed-modules:     Lib
  build-depends:       base >= 4.7 && < 5
  default-language:    Haskell2010

executable stapro-exe
  hs-source-dirs:      app
  main-is:             Main.hs
  ghc-options:         -threaded -rtsopts -with-rtsopts=-N
  build-depends:       base
                     , stapro
  default-language:    Haskell2010

test-suite stapro-test
  type:                exitcode-stdio-1.0
  hs-source-dirs:      test
  main-is:             Spec.hs
  build-depends:       base
                     , stapro
                     , HUnit
                     , Main
  ghc-options:         -threaded -rtsopts -with-rtsopts=-N
  default-language:    Haskell2010

...

您似乎在尝试依赖可执行文件(test-suite 部分 build-depends 中的 Main),以便您可以在测试套件中对其进行测试。那行不通,事实上您根本无法真正测试您的可执行文件。

build-depends 中删除 Main。将您要测试的所有代码移到您的库中。