Feature request : bump git commit

[alanz]

At the moment, a specific commit has to be specified for a dependency, as in

packages:
- '.'
- location:
    git: git@github.com:alanz/ghc-mod
    commit: 526714aed7592c6d548ce38e9935bef0a984217b

I would like to be able to issue a command something like

stack bump ghc-mod wip

This would update the commit to reflect the currrent HEAD of the wip branch in the git@github.com:alanz/ghc-mod repository.

A possible enhancement would be to include a branch: wip field to the location, and then

stack bump

could update all the remote repositories.

[mboes]

The difficulty here is that it means that stack has to poke at and rewrite a file written by a human, retaining any formatting and all. The git repo support is meant for simple use cases, and it would be a shame to have it grow to ultimately reimplement entirely what git submodule already provides. If you make heavy use of external git repos, I would suggest using git submodule instead. It is equivalent to git: <repo> above and has much more functionality besides, in particular "bump" functionality as you request, in the form of

$ git submodule update --remote
$ git commit -a

[snoyberg]

I'm overall -1 on adding this functionality, though if someone sends a PR I'd probably accept it.

[snoyberg]

It doesn't look like this is something that's planned to be implemented, so closing.