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sfink • last Tuesday at 4:03 PM • 1 reply • view on HN

I'm about the same. jj is kind of perfect for that. Example:

# I've finished something significant! Carve it out from the working "change" as its own commit.

    `jj commit --interactive` # aka `jj commit -i` or `jj split`, depending on how you prefer to think of it: making a commit for some work, or splitting a separate commit out of the working change.
# Oops, missed a piece.

    `jj squash --interactive` # aka `jj squash -i`
# Let me look at what's left.

    `jj diff`
# Oh right, I had started working on something else. I could just leave it in the working change, but let me separate it out into its own commit even though it's unfinished, since I can always add pieces to it later.

    `jj commit -i`
# Wait, no, I kind of want it to come before that thing I finished up. Shoot, I messed up.

    `jj undo`
# Let me try that again, this time putting it underneath.

    `jj split -B @-` # aka `jj split --insert-before @-`. @ is the working change, @- is its immediate parent(s), @-- is all grandparents, etc.
# Note that instead of undoing and re-selecting the parts, you could also `jj rebase -r @- -B @--` to reorder. And in practice, you'll often be doing `jj log` to see what things are and using their change ids instead of things like `@--`.

# I also have some logging code I don't need anymore. Let me discard it.

    `jj diffedit`
# Do some more work. I have some additions to that part I thought was done.

    `jj squash -i`
# And some additions to that other part.

    `jj squash -i --into @--`
# etc.

There's a lot more that you could do, but once you internalize the ideas that (1) everything is a commit, and (2) commits (and changes) can have multiple parents thus form a DAG, then almost everything else you want to do becomes an obvious application of a small handful of core commands.

Note: to figure out how to use the built-in diff viewer, you'll need to hover over the menu with the mouse, but you really just need f for fold/unfold and j/k for movement, then space for toggle.

Replies

em-bee • last Wednesday at 3:17 AM

# I've finished something significant! Carve it out from the working "change" as its own commit.

    git add -p
    git commit
# Oops, missed a piece.

    git add -p
    git commit --amend
# Let me look at what's left.

    git diff
# Oh right, I had started working on something else. I could just leave it in the working change, but let me separate it out into its own commit even though it's unfinished, since I can always add pieces to it later.

    git add -p
    git commit
# Wait, no, I kind of want it to come before that thing I finished up. i didn't mess up, this is standard procedure

    git rebase -i <some older commit ref> # put commits into the desired order.
# I also have some logging code I don't need anymore. Let me discard it.

don't know what jj does here

    edit files
or

    git revert -p
# Do some more work. I have some additions to that part I thought was done.

    git add -p
    git commit
    git rebase -i <some older commit ref> # choose the right place and then tell git to squash into the parent
# And some additions to that other part.

    git add -p
    git commit
    git rebase -i <some older commit ref> # as above
you list a number of different commands that i do in git always with the same sequence of commands. i don't see how jj makes those examples any easier. it looks like maybe they help you get away with not understanding how git works, by instead giving you more commands that do specifically what you want.
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