cabal-install haddock-project includes sub-libraries with visibility: hidden

[recursion-ninja]

Describe the bug
The cabal haddock-project produces, as part of it's indexed output, sub-libraries which ought to be omitted due to being annotated as visibility: hidden in the package description $pkg.cabal file.

To Reproduce
Steps to reproduce the behavior:

$ git clone https://github.com/recursion-ninja/includes-hidden-sublibraries
$ cd includes-hidden-sublibraries
$ cabal haddock-project
$ grep Lib2 haddocks/index.html

Expected behavior
The contents of haddocks/index.html should not include Lib2 because includes-hidden-sublibraries.cabal specifies that lib2 is not a public facing library via the visibility: private build field.

The grep command in the example above should produce no output because Lib2 was not included in the generated Haddock documentation.

System information

• MacOS

• Cabal

$ cabal --version
cabal-install version 3.10.3.0

• GHC

$ ghc --version
The Glorious Glasgow Haskell Compilation System, version 9.10.1

• Haddock

$ haddock --version
Haddock version 2.28.0, (c) Simon Marlow 2006
Ported to use the GHC API by David Waern 2006-2008