hackport.cabal: Fix doctest-v2

build-tool-depends doesn't play nice with Setup.hs installs, and tries
to rebuild cabal-install/doctest locally. This has recently caused some
compilation errors so there is now a 'ci-depends' flag to toggle between
build-tool-depends (for CI systems) and build-depends (for users with
the needed tools installed to their system).

This reverts commit 51bc8c1.

See: gentoo-haskell/gentoo-haskell#1074
See: haskell/cabal#8434
Signed-off-by: hololeap <hololeap@users.noreply.github.com>

.github/workflows/haskell.yml

@@ -55,11 +55,11 @@ jobs:
     - name: Configure
       run: |
         cabal update
-        cabal configure --enable-tests --enable-benchmarks --flag=pedantic
+        cabal configure --enable-tests --enable-benchmarks --flag=pedantic --flag=ci-depends
     - name: Install dependencies
       run: |
         cabal build --only-dependencies
     - name: Build
       run: cabal build
-    - name: Run spec test
-      run: cabal test --test-option=--color --test-show-details=streaming spec
+    - name: Run all enabled tests
+      run: cabal test --test-option=--color --test-show-details=streaming

hackport.cabal

@@ -44,6 +44,11 @@ flag profile
   default:     False
   manual:      True
 
+flag ci-depends
+  description: Enable build-tool-depends for use with CI systems
+  default:     False
+  manual:      True
+
 -- Turn off all warnings (for external libs and doctests-v2)
 common no-warnings
   ghc-options: -Wno-default -Wno-incomplete-uni-patterns
@@ -1026,9 +1031,6 @@ test-suite doctests
 
 test-suite doctests-v2
   import:             warnings
-  -- doctests-v2 is causing problems, looking for ghc lib and alex on
-  -- github CI. This may be fixable.
-  buildable:          False
   type:               exitcode-stdio-1.0
   default-language:   Haskell98
   hs-source-dirs:     tests/doctests-v2
@@ -1037,9 +1039,15 @@ test-suite doctests-v2
     , base
     , process
 
-  build-tool-depends:
-    , cabal-install:cabal  >=3.4
-    , doctest:doctest      >=0.8
+  if flag(ci-depends)
+    cpp-options: -DCI_DEPENDS
+    build-tool-depends:
+      , cabal-install:cabal  >=3.4
+      , doctest:doctest      >=0.8
+  else
+    build-depends:
+      -- cabal-install should already be installed if this is being built...
+      , doctest       >=0.8
 
   if flag(cabal-v1)
     buildable: False
@@ -1087,5 +1095,10 @@ test-suite spec
     , time
     , xml
 
-  build-tool-depends: hspec-discover:hspec-discover >=2.0
+  if flag(ci-depends)
+    cpp-options: -DCI_DEPENDS
+    build-tool-depends: hspec-discover:hspec-discover >=2.0
+  else
+    build-depends:
+      , hspec-discover
   other-extensions:   DeriveDataTypeable

tests/doctests-v2/Main.hs

@@ -1,14 +1,19 @@
+{-# LANGUAGE CPP #-}
+
 module Main (main) where
 
 import Data.Foldable (for_)
 import System.Exit (ExitCode (..), exitWith)
-import System.Process (readProcess, createProcess, proc, waitForProcess, getProcessExitCode)
+import System.Process
 
 
 main :: IO ()
 main = do
-
+#if defined(CI_DEPENDS)
     doctestPath:_ <- lines <$> readProcess "cabal" ["list-bin", "doctest"] []
+#else
+    let doctestPath = "/usr/bin/doctest"
+#endif
 
     let components =
             [ "hackport:lib:hackport-internal"