Support for stack setup installing + booting GHCJS

[mgsloan]

See #749 (comment) for more info - this isn't expected to work out of the box, since ghcjs source tarballs need to be available and listed in stack-setup-2.yaml

[snoyberg]

👍 LGTM. I'd like to test this before we merge to master. Can you update the stack-setup-2.yaml file and ping me when it's ready?

[mgsloan]

@snoyberg Ready! commercialhaskell/stackage-content@9ef1c12

[snoyberg]

I can confirm that this worked to get GHCJS installed and usable. Please merge when you're ready.

[snoyberg]

Oh, forgot to mention: please add a comment to the ChangeLog about this (and yes, this counts as a major feature)

[fizruk]

@mgsloan how did you make a proper pre-release of GHCJS?

I am trying to use latest GHCJS with Stack and managed to make it work with this in my stack.yaml:

resolver: ghcjs-0.2.0.20150930_ghc-7.10.2
compiler-check: match-exact
setup-info:
  ghcjs:
    source:
      ghcjs-0.2.0.20150930_ghc-7.10.2:
        url: "https://github.com/fizruk/ghcjs/archive/v0.2.0.20150930.tar.gz"

But that .tar.gz archive is not a proper pre-release (e.g. it does not have lib/cache/boot.tar), so I had to tweak Stack locally to pass --dev flag to ghcjs-boot. I would love to make this a proper archive so that others might be able to use it, but can't find any documentation on how to do this.

[mgsloan]

@fizruk It depends on if you are making a pre-release for master (improved-base) or old-base. If making one for old-base, first you must install and boot GHCJS. Then, run cabal sdist. With master, the process is easier and only cabal sdist is needed.

[fizruk]

@mgsloan I need master (improved base). So am I right that for master I don't need ghcjs-boot step? It seemed like ghcjs-boot did a lot of work compared to GHCJS install step.

[fizruk]

@mgsloan oh, there is non-trivial Setup.hs affecting cabal sdist. Will stack sdist also work?

[fizruk]

I have successfully set up latest GHCJS with Stack:

resolver: ghcjs-0.2.0.20151001_ghc-7.10.2
compiler-check: match-exact
setup-info:
  ghcjs:
    source:
      ghcjs-0.2.0.20151001_ghc-7.10.2:
        url: "https://github.com/fizruk/ghcjs/releases/download/v0.2.0.20151001/ghcjs-0.2.0.20151001.tar.gz"

@mgsloan maybe it is worth including it in stack-setup-2.yaml?