Proposal - Add EVM (emacs version manager) to deal with emacs versions on travis

[ardumont]

Again, it's a proposal (this eases the .travis.yml's readability).

Also, this reduces the use of Damien Cassou's PPA which is no longer
maintained.

What are the targeted versions for emacs?

At the moment, it's ok with emacs-24.3 and emacs-24.4 but otherwise, there are limitations:

• emacs-23.4 -> limit from cask not supporting before emacs 24
• emacs 24.1 -> pb in ghc-core.el regarding cl-lib
• emacs 24.2 -> the same

Cheers,

[gracjan]

@ardumont: I have a bit of trouble following what you did here. There are 5 commits, most of them seem to unrealed to EVM... Can you somehow explain what is going on?

[ardumont]

Hello,

@ardumont: I have a bit of trouble following what you did here. There are 5 commits, most of them seem to unrealed to EVM...

It's difficult to follow because it's now out of context.

Can you somehow explain what is going on?

I proposed in order 3 PR with separate concerns (but depending on each other):

• Proposal - Add haskell-process-wrapper-function #370 to permit the use of haskell-process-wrapper-function (use of nix-shell, docker, ...).
  This introduced some unit tests because I wanted to be certain not to break this awesome mode.
  But for this, I add to make 1 quick hack to permit the triggering of tests.

This PR has been closed but the main functionality has been merged by @chrisdone (via cherry-picking) because it was on a major refactoring on the side.

I believe the tests have not been integrated.

• other PR Proposal - Add Cask to deal with test dependencies #372 to fix the hack that triggered the tests using cask (a better solution than the previous hack).
• this one which permits the use of evm.

I believe that this can:

• either be closed if haskell-mode maintainers are not interested by this.
• either you are interested, thus, I need to rebase the code, remove the needless commits and see what's wrong.

Does this make better sense to you?

Cheers,

[ardumont]

I remembered right, the tests have not been merged: #370 (comment)

[gracjan]

@purcell: I refer to you as my Emacs knowledge is not good enough to see what is needed here.

[purcell]

@ardumont Where does ~/.evm come from? 0f4bd9f adds references to it, but I don't understand how that all comes together.

[ardumont]

@ardumont Where does ~/.evm come from? 0f4bd9f adds references to it, but I don't understand how that all comes together.

It's installed here 0f4bd9f#diff-354f30a63fb0907d4ad57269548329e3R21

(Oh and I need to update this PR if you are still interested by this.)

[ardumont]

Just rebased this PR with latest code.

To keep up with what I just said @purcell, this https://github.com/haskell/haskell-mode/pull/373/files#diff-354f30a63fb0907d4ad57269548329e3R21 is what installs evm.

[ardumont]

@gracjan's PR #477 seems to do the same with less limitations than this one.

@purcell I think we can close this one, what do you think?

[purcell]

Yes, thanks. #477 is now applied.