Sapling-like revset navigation

[mbStavola]

One of the things I really enjoyed from Sapling was the ability to just say sl prev and sl next to move around. I was pretty bummed when I didn't see an equivalent in jj... but then I discovered the awesome power of revsets and the amazing revset-alias config option. Now I'm happy as can be 😄

Anyway, just thought I'd share for those who were looking for something similar:

[revset-aliases]
'prev' = '@-'
'next' = '@+'
'top' = 'latest(@:)'
'bottom' = 'latest(:(~:@) & :@)+ & :@'

Since they're just revsets you can use them in most contexts like so:

jj edit prev
jj co next
jj log -r bottom..top

[thoughtpolice]

Note that analogues for prev and next will be implemented in #1200; hopefully it'll go in sometime soon!

[mbStavola]

Ah! Totally missed that one, really cool to see this becoming a native feature of jj.

Still glad I messed around with this, if only to learn more about revsets 😄

[ilyagr]

The 'top` and 'bottom' aliases are neat!

I'm guessing you usually jj edit commits. I use slightly different aliases since I usually jj new commits and then jj amend. So, I replace @ with @-. Unfortunately, I have to also do some extra gymnastics so that the current commit doesn't affect the outcome:

[revset-aliases]
'prev' = '@--'
'next' = '@-+~@'
'top' = 'latest(@-:~@:)'
'bottom' = ? # haven't translated this one yet, might update this later.

(I've used the first two for a while, I'll start using the top and bottom now that you showed them to me).

I'd love to build these aliases in; I wonder if there's some way to do it so that both workflows are supported. One option is to have two versions of each. However, that's not very elegant, and I can't come up with decent names for these.

[arxanas]

• git-branchless supports git prev/git next with the -a/--all flags to avoid having an extra top/bottom alias. But that only works if there's a notion of the "current commit stack" or "main branch".
• It would be nice to have a stack() revset so that top() is just roots(stack()) and bottom() is heads(stack()).

[mbStavola]

The 'top` and 'bottom' aliases are neat!

Thank you, they were also fun to figure out! I'm still thinking that bottom can be simplified somehow, but I don't quite see it just yet.

I'm guessing you usually jj edit commits. I use slightly different aliases since I usually jj new commits and then jj amend.

Usually is giving me a bit too much credit 😛-- I really just started playing with jj last night so I'm still figuring out what works for me and what my preferences are. You're correct in that I've been heavily using jj edit, but now I'm wondering if new + amend may actually make more sense for me. Just to update my mental model a bit, can you tell me why you prefer one over the other?

I'd love to build these aliases in

That would be awesome.

I wonder if there's some way to do it so that both workflows are supported.

Kinda dirty but, you could add a revset function like relativize_to_command() which would add the command's intended "target" to the passed in revset. That is, depending on the command it may append an operator to the revset passed in.

For example, consider what the commands target. The edit command will select the exact revset you specify whereas the new command will always create a new commit one after the specified revset. You can think of this being roughly x and x-[0].

So, given:

[revset-aliases]
'prev' = 'relativize_to_command(@-)'

jj edit prev would evaluate to @- and jj new prev would evaluate to @--... or something like that. Maybe that's a bit too magic for revset functions, but it's one possible solution.

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[0]: though not exactly, because it's going to be a new revision not an existing one but I digress