unit-testing - 尽管有测试失败，但运行 “cabal test” 通过

Question

我有一个 cabal 测试目标:

test-suite Tests
  type:              exitcode-stdio-1.0
  main-is:           Main.hs
  hs-source-dirs:    test, src
  build-depends:     base, …
  default-language:  Haskell2010

和一个简单的测试 Main.hs :

import Test.HUnit
testSanity = TestCase $ assertEqual "Should fail" 2 1
main = runTestTT testSanity

正在运行 cabal test通过:

Test suite Tests: RUNNING...
Test suite Tests: PASS
Test suite logged to: dist/test/Project-0.1.0-Tests.log
1 of 1 test suites (1 of 1 test cases) passed.

即使在测试套件日志中正确记录了失败:

Test suite Tests: RUNNING...

Cases: 1  Tried: 0  Errors: 0  Failures: 0

### Failure:
Should fail
expected: 2
 but got: 1
Cases: 1  Tried: 1  Errors: 0  Failures: 1
Test suite Tests: PASS
Test suite logged to: dist/test/Project-0.1.0-Tests.log

我究竟做错了什么？

Answer 1

main必须是 IO a 类型在哪里 a可以是任何东西，并且该值与程序的 POSIX 退出状态没有任何关系。您需要查看 Counts由 runTest 返回并明确选择成功或失败的输出代码。

import System.Exit

main :: IO ()
main = do
    cs@(Counts _ _ errs fails) <- runTestTT testSanity
    putStrLn (showCounts cs)
    if (errs > 0 || fails > 0) 
        then exitFailure
        else exitSuccess