Feature request: Merge tool support

[Caleb-T-Owens]

It would be great if we could have an option to open a merge tool whenever entering edit mode if there are conflicts.

[difftool "codecompare"]
    cmd = \"C:\\Program Files\\Devart\\Code Compare\\CodeCompare.exe\" -W \"$LOCAL\" \"$REMOTE\"
    renames = true

[mergetool "codecompare"]
    cmd = \"C:\\Program Files\\Devart\\Code Compare\\CodeMerge.exe\" -MF \"$LOCAL\" -TF \"$REMOTE\" -BF \"$BASE\" -RF \"$MERGED\"
    trustExitCode = true

It would be interesting to consider whether we should simply shell out and make a call to git mergetool or whether it would be best to call the programmes ourselves.

I'd lean towards just shelling out to git mergetool so we don't have to handle the complexity (that undoubtedly exists) ourselves.

@Byron @schacon Do you have any thoughts/experience in this area?

[Byron]

I like the idea, and also think it makes sense in the context of Resolving Conflicts to make opening configured merge-tools easier. I'd also try to use git mergetool first.

However, before offering this up I think I'd check to see if anything is any merge.guitool (or similar) is configured which should mean that it will be spawning independently, in order to avoid launching anything that only works only in a terminal, where people would invoke it themselves.

[Caleb-T-Owens]

🤔 We could hook up something like https://xtermjs.org for std in/out

[Byron]

Even though I'd find it technically interesting to hookup a web-view with a process that somehow is thinking the browser is a TTY, as a terminal user, I definitely prefer my terminal along with my own everything. Nicely separated in its own window as well.

An alternative question would be if it's possible to make integration with terminal-bound programs better. Launching programs within the environment of a login-shell is one thing, but launching it in a login shell in a terminal is yet another. Also, my brain wants to melt when thinking about the portability aspects of this 😅.

[Caleb-T-Owens]

Some days I think it would be easier to ship a mac with each copy of GitButler 😆