Automatically running unit tests in Haskell - haskell

Question

Is there a way to run my test suites with my build command? All I can find is that I can run e.g. cabal test after cabal build. What I want is a way to automatically run my tests when running e.g. cabal build.
I want a solution that will automate this for anyone building the package without requiring them to run a different script. An analogy would be a java build script where the default build target runs unit tests after compiling.

Answer 1

You can use a cabal.project.local to do this when using cabal v2 projects (as in, cabal v2-build which is the default and thus the same as cabal build for cabal version 3.0 and up).
The strategy is just to place a cabal.project.local file in the build directory with contents of:
tests: true

Answer 2

I find this a really bad idea since it's unexpected, non-canonical behavior that breaks cross-compilation, but you can probably hack it together with a Custom build type.
Here's an example mypackage.cabal:
cabal-version: >=2.0
name: mypackage
version: 0.1.0.0
author: None
maintainer: none#example.com
build-type: Custom
custom-setup
setup-depends:
base >= 4.5,
Cabal >= 2.0
executable mypackage
main-is: Main.hs
build-depends: base >= 4
default-language: Haskell2010
test-suite test
type: exitcode-stdio-1.0
build-depends: base >= 4
main-is: Test.hs
and a corresponding Setup.hs:
import Control.Monad
import Distribution.Simple
import Distribution.Simple.Setup
import Distribution.Simple.Test
import Distribution.Simple.Build
main = defaultMainWithHooks simpleUserHooks {
postBuild = myPostBuild
}
myPostBuild args flags desc info =
when ("exe:mypackage" `elem` buildArgs flags) $ do
build desc info defaultBuildFlags { buildDistPref = buildDistPref flags } []
test ["test"] desc info defaultTestFlags {
testDistPref = buildDistPref flags
}
This does result in a project where cabal build also builds and runs the tests on my Cabal 3.0.0.0 system, but I don't know which additional caveats this has.