ghcup install-cabal is problematic

cabal new-install cabal-install will not overwrite the old binary, but we want it to. So how does the user upgrade from pre-built binary downloaded by ghcup to latest cabal-install?

I recommend putting cabal into ~/.ghcup/bin not ~/.cabal/bin, and then have the user set up their PATH like

export PATH=$HOME/.cabal/bin:$HOME/.ghcup/bin:$PATH

which means a cabal new-install cabal-install will put the updated version in priority position.

cabal-install has a bug right now where it doesn't warn about the existing symlink but they know about it.

@fommil re that not-warning issue, there's already https://github.com/haskell/cabal/pull/5602 as a preliminary mitigation (for the upcoming 2.4 point rls) until a full fix of https://github.com/haskell/cabal/issues/5491 is available

and then have the user set up their PATH like

That's exactly what I want to avoid. It's more configuration, can be done wrong, be forgotten, ...

cabal new-install should allow to overwrite existing files via something like --force.

ok, in that case should we just close this since it will be fixed by upstream cabal?

@fommil the PR that landed yesterday for the next point rls of cabal 2.4 will merely emit warnings if it couldn't overwrite a symlink. So unless somebody steps up and offers to help with implementing a full fix for haskell/cabal#5491 which would involve providing something like --force, this will probably only happen for cabal 3.0.

The full fix is in and the next cabal-install point release will include it.

edit: haskell/cabal#5638

2.4.1 is out