change the default of cabal v2-configure

[phadej]

It says:

The 'cabal.project.local' file persists across 'clean' but is overwritten
on the next use of the 'configure' command. The intention is that the
'cabal.project' file should be kept in source control but the
'cabal.project.local' should not.

but I often have non-trivial configuration there, e.g.

package Cabal
  ghc-options: -Werror

and if I accidentally cabal v2-configure, that setup is gone. As cabal.project.local files aren't checked into VCS, overwriting them is destructive, and irreversible operation.

I suggest v2-configure to abort if cabal.project.local exists. And possibly have a --force flag.

[23Skidoo]

package Cabal
  ghc-options: -Werror

Why not put this stuff in cabal.project?

[phadej]

Because cabal.project **is** checked to VCS, and I try to avoid cabal.project changes as I could accidentally commit them.

…

On 26 Apr 2019, at 20.16, Mikhail Glushenkov ***@***.***> wrote: package Cabal ghc-options: -Werror Why not put this stuff in cabal.project? — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub, or mute the thread.

[23Skidoo]

OK. May be easier to introduce a new local config file (cabal.project.user or cabal.project.extra) file for such customisations.

[hvr]

btw, in order to address this very issue we already implemented a failsafe when this came up some time ago already: when you v2-configure a backup of the old file is created at cabal.project.local~; see #3943

and therefore

As cabal.project.local files aren't checked into VCS, overwriting them is destructive, and irreversible operation.

is not fully accurate.

[ulysses4ever]

Not much activity here: I take it people have been satisfied with the current behavior of configure, where it backs up an existing cabal.project.local, if any. Maybe this could be closed?

[Mikolaj]

Also, there's been some major activity about it in #7402 (and minor in #6877), so this is probably quite obsolete. Closing. Thank you, everybody.

[fgaz]

There's also the --enable-append option that can be set globally in ~/.cabal/config

[andreasabel]

I take it people have been satisfied with the current behavior of configure, where it backs up an existing cabal.project.local,

I am not, see #8408.