cabal-install does not install data-files

[StefanK]

Installing a package with

cabal clean
cabal configure --user --prefix="${HOME}/opt"
cabal build
cabal install

does not copy the data-files listed in the project.cabal file to the desired destination. It does not copy them anywhere at all. I would expect them to end below something like /home/sk/opt/share/project-0.1, as is reported by function Paths_project.getDataFileName.

I'll attach a toy project demonstrating this.

System:

sk@watarrka:~> ghc --version
The Glorious Glasgow Haskell Compilation System, version 6.12.1

sk@watarrka:~> cabal --version
cabal-install version 0.8.0
using version 1.8.0.2 of the Cabal library 

[StefanK]

the cabal file from the zipped archive, for easier viewing

[duncan]

This is a duplicate of #645.