[Haskell-cafe] Cabal, sdist and flags

[Magnus Therning]

A while ago I moved a project away from using a mix of Cabal and make
to build (Cabal to build the library and make to build the tests) to
using only Cabal.  I added a flag and then made a construct like this:

  flag BuildTests
      Description: Build unit and quickcheck tests.
      Default: False
  ...
  executable tests
      if flag(BuildTests)
          main-is: Test.hs
          build-depends: test-framework, test-framework-hunit, HUnit,
test-framework-quickcheck2, QuickCheck >= 2.1.0.0
          hs-source-dirs: test-src src
      else
          main-is: Test.hs
          buildable: False

Interestingly that does work for things like 'configure' and 'build',
but it doesn't work for 'sdist':

  % ./Setup.hs sdist
  Distribution quality errors:
  Building source dist for dataenc-0.13.0.1...
  Setup.hs: Test.hsTest.hs doesn't exist

To make this work I had to move the 'main-is' outside of the if-else:

  executable tests
      main-is: Test.hs
      hs-source-dirs: test-src src
      if flag(BuildTests)
          build-depends: test-framework, test-framework-hunit, HUnit,
test-framework-quickcheck2, QuickCheck >= 2.1.0.0
      else
          buildable: False

I found this surprising, so I'm tempted to call it a bug.  A quick
search didn't tell me whether this is well-known already, hence the
email.  Would you consider it a bug?  Has it been raised already?

/M

-- 
Magnus Therning                        (OpenPGP: 0xAB4DFBA4)
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