haskell - How to use HUnit in Stack -

i have stackproject stapro file app/main.hs

module main  import lib  main = putstrln "this main"   foo::int ->int foo = (+1) 

and file test/spec.hs

module spec  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) 

when try execute tests however

$ stack test while constructing buildplan following exceptions encountered:  --  while attempting add dependency,     not find package main in known packages  --  failure when adding dependencies:           main: needed (-any), stack configuration has no specified version     needed package stapro-0.1.0.0 

my .cabal file is

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  ... 

it looks you're trying depend on executable (main in build-depends of test-suite section), can test in test suite. doesn't work, in fact can't test executable @ all.

remove main build-depends. move code want test library.