Is there a way to use $EDITOR as the merge-tools program?

[heygarrett]

What I have currently:

[merge-tools.nvimdiff]
program = "nvim"
merge-args = ["-c", "JJdiff", "-d", "$left", "$output", "$right"]

What I'd like to do:

[merge-tools.nvimdiff]
program = "$EDITOR"
merge-args = ["-c", "JJdiff", "-d", "$left", "$output", "$right"]

For context, my EDITOR is set to env ENV_EDITOR=1 nvim

[ilyagr]

I don't believe there's a built-in way.

You could make your own script like

#!/bin/sh
$EDITOR "$@"
# **Update/quick fixup:** There should *not* be quotes around $EDITOR

If you make it exectuable, call it myeditor, and put it in the PATH, replacing nvim with myeditor should work.

IIRC, Some systems (Debian derivatives, I think) have a /usr/bin/editor binary to call $EDITOR already built-in. Update: Though, its logic might be slightly different, and/or I may have misremembered the name. See also https://www.mankier.com/1/sensible-editor.

Update 2: Yeah, /usr/bin/editor is a symlink to something like vim (and you can probably point it to nano or something using update-alternatives). So, it wouldn't set the env var you wanted. sensible-editor would work if you have it; having your own script would be more portable.

---

Alternatively, you could use

[merge-tools.nvimdiff]
program = "env"
merge-args = ["ENV_EDITOR=1", "nvim", "-c", "JJdiff", "-d", "$left", "$output", "$right"]

---

Aside: there's also a separate issue that we might want a feature with a possible name of jj resolve --edit that opens the conflict in jj's default editor, even if the conflict is too complicated for a 3-way merge.

[heygarrett]

Thanks for the suggested workarounds! The program = "env" idea is probably what I'll go with (I'm on macOS, so I don't have /usr/bin/editor or sensible-editor), but it did get get me wondering if I could do something like this:

[merge-tools.nvimdiff]
program = "command"
merge-args = ["$EDITOR", "-c", "JJdiff", "-d", "$left", "$output", "$right"]

Unfortunately that doesn't appear to work:

~/d/s/jj/testrepo
❯ jj resolve
Resolving conflicts in: fruits.txt
/usr/bin/command: line 4: $EDITOR: command not found
Error: Failed to resolve conflicts
Caused by: Tool exited with exit status: 127 (run with --debug to see the exact invocation)

Would it be realistic to file a feature request to support $EDITOR as the merge-tools program?

[yuja]

As ilyagr suggested, you'll need to use sh to expand $EDITOR environment variable. Something like this might also work (see jj util exec --help for the trick):

program = 'sh'
merge-args = ['-c', 'exec $EDITOR "$@"', '--', ...]

I don't think we'll want to add support for environment variables expansion at arbitrary places. Even if we had that, program = "$EDITOR" wouldn't work if $EDITOR had command name and arguments inline.

[heygarrett]

Ah, that works! Thanks!