@phadej, does this change sound reasonable?

Does this actually work?

With:

cabal-version: 2.4
name: pkkg
version: 0

executable foo
  default-language: Haskell2010
  main-is: exe.hs
  build-depends: base

module Main (main, foo) where

foo :: Int
foo = 42

main :: IO ()
main = print foo

and

% cabal --version
cabal-install version 3.6.2.0
compiled using version 3.6.2.0 of the Cabal library 

trying to cabal haddock all fails:

% cabal haddock all
cabal: renderBuildTargetProblem: unexpected status (TargetDisabledByUser,Nothing)
CallStack (from HasCallStack):
  error, called at src/Distribution/Client/CmdErrorMessages.hs:356:14 in main:Distribution.Client.CmdErrorMessages

I tried to find an issue in cabal-install about this behavior, but could find it. Is it fixed recently?

Does this actually work?

Seems like for your example, no haddock is actually run.

I tried to find an issue in cabal-install about this behavior, but could find it. Is it fixed recently?

I can confirm that the error is gone on cabal-install master.

Seems like one has to pass --haddock-executables to silence the warning:

No documentation was generated as this package does not contain a library.
Perhaps you want to use the --haddock-executables, --haddock-tests,
--haddock-benchmarks or --haddock-internal flags.

Let me try to investigate further... (I remembered it worked fine on hackage-server, but I have to revisit the details).

hackage-server probably works cause it has internal libraries. But if we can build haddocks with --haddock-all to build haddocks for exes, tests and benchmarks, that will be great. These should generally succeed, there is no reason to have invalid markup in the auxiliary components (even if Hackage won't render/display it, IDEs may, I guess).

@phadej wrote:

I tried to find an issue in cabal-install about this behavior, but could find it. Is it fixed recently?

Looks like it is still open:

• cabal new-haddock produces no documentation for single module executables haskell/cabal#5890

hackage-server probably works cause it has internal libraries.

Yes, reading up on haskell/cabal#5890 confirms this: if you have other-modules, docs are generated. Thus, your example just hit the case that doesn't work.

But if we can build haddocks with --haddock-all to build haddocks for exes, tests and benchmarks, that will be great.

Since cabal v2-haddock --haddock-all does not fail (even if it does not produce any HTML), unless there is invalid markup, it might be no harm to run it by default, as you said.

A few successful CI runs:

• https://github.com/andreasabel/cabal-clean/runs/6249085026?check_suite_focus=true
• https://github.com/andreasabel/agda2lagda/actions/runs/2254675955
• https://github.com/andreasabel/risc386/actions/runs/2254519652

Merged in #585 (please don't edit version in the future if it's release i.e. even version).

Merged in #585

Thanks!

(please don't edit version in the future if it's release i.e. even version).

Ok, understood.