Non-interactive hunk-level operations for Jujutsu. Scriptable alternative to jj split's interactive mode.

Requires jj v0.41.0.

Install#

cargo install --git https://tangled.sh/akashina.tngl.sh/jjc  # or from local checkout:
cargo install --path .

Commands#

jjc hunks — list hunks#

jjc hunks                    # list all hunks in @
jjc hunks --from main        # list hunks in a specific revision
jjc hunks -r @-              # shorthand for --from
jjc hunks abc123             # inspect a single hunk (by ID or prefix)
jjc hunks --full             # include numbered diff lines
jjc hunks --blame            # annotate each line with originating commit

--from accepts any revset that resolves to one revision. Hunks are listed for that revision's diff against its parent, so jjc hunks --from @- shows the parent commit's own hunks rather than the working copy's hunks.

Default output shows a changed-lines preview (up to 4 lines):

a1b[2c3d4e5f6] src/main.rs (+3 -1)
  +    println!("new line");
  -    old_call();

f09[8a7b6c5d4e] src/lib.rs (+1 -0)
  +use std::io;

--full adds context lines with line numbers, and lists change atoms when a hunk has more than one:

a1b[2c3d4e5f6] src/main.rs (+3 -1)
  1: fn main() {
  2:+    println!("new line");
  3:-    old_call();
  4: }
  a1b[2c3d4e5f6]#1 @2 a1b[2c3d4e5f6]#2 @3

Hunk IDs use bracket-style prefix highlighting (same as jj log): a1b[2c3d4e5f6] means a1b is the shortest unique prefix.

jjc pick — split hunks into a new commit#

jjc pick a1b -m "extract logging"        # pick entire hunk
jjc pick a1b#2 -m "fix off-by-one"       # pick a single change atom
jjc pick a1b@15-20 -m "refactor"         # pick by target line range
jjc pick a1b c3d -r foo -m "partial"     # pick multiple hunks from revision foo

Creates a new commit with the selected hunks, then rewrites the source revision on top of it (like jj split but non-interactive).

jjc drop — revert hunks to parent content#

jjc drop a1b           # drop a hunk from @
jjc drop a1b c3d       # drop multiple hunks

Rewrites the revision in place with selected hunks reverted. Like "Revert Hunk" in a diff editor.

jjc fold — squash hunks into another revision#

jjc fold a1b --into main              # fold hunk from @ into main
jjc fold a1b -r feat --into main      # fold from a specific source
jjc fold --select feat:a1b,c3d        # multi-source with explicit assignment

Hunk selectors#

All write commands (pick, drop, fold) accept hunk selectors:

Use jjc hunks to discover IDs and atom indices.

How it works#

jjc reads the jj repository directly via jj-lib. It loads your jj config (user, repo, workspace layers), snapshots the working copy, and commits transactions with proper descendant rebasing and working copy updates. No jj commands are shelled out or proxied.

Limitations#

• Only text file hunks are supported. Binary files, renames, copies, additions, and deletions are listed as unsupported.
• Immutable commit checking is minimal (root commit only). Use jj log to verify before rewriting shared history.