Files
buzz/bin
Will Pfleger cd0d33f085 fix(hooks): scope pre-push lanes to branch merge-base diff (#6423)
Lefthook selected pre-push lanes from the file set `git diff --name-only
HEAD @{push}` returns, which is overinclusive two different ways:

- **Rebase/merge poisoning.** `@{push}` is a two-dot diff against the
branch's last-pushed tip. After a rebase onto newer main — or the `git
merge origin/main` that `check-branch-skew.sh` itself instructs agents
to run — that diff includes everything `main` changed since the last
push, so `mobile-checks`, the `desktop-*` lanes, and `rust-tests` fire
on branches that never touched those trees (a recent relay-only push
discovered 266 files, 26 of them `mobile/`).
- **Brand-new branch in a worktree.** When `@{push}` doesn't resolve,
lefthook reads `$GIT_DIR/refs/remotes/origin/HEAD` — which doesn't exist
in a linked worktree's git-dir — then falls back to the
alphabetically-first `HEAD ->` remote. In a clone with a stale
third-party remote sorted before `origin`, that diffs against a frozen
tip and runs the full suite. All agent work happens in worktrees.

## Fix

Add `files: git diff --name-only origin/main...HEAD` to the six globbed
pre-push lanes (`rust-tests`, `desktop-check`, `desktop-typecheck`,
`desktop-test`, `desktop-tauri-checks`, `mobile-checks`). The three-dot
form is the branch's merge-base diff against `origin/main` — the same
base resolution `scripts/check-file-sizes-core.mjs` (`resolveBaseRef`)
and CI's dorny/paths-filter already use. A lane now fires only when this
branch actually changed a file it covers; `main`-side changes never
re-trigger it, and a new branch diffs against `origin/main` (empty diff
→ all globbed lanes skip) rather than a stale remote. `branch-skew` and
`file-size-check` stay unfiltered by design.

Also pin hook dispatch to the Hermit-managed lefthook. The generated
`.git/hooks/*` dispatchers prefer `$LEFTHOOK_BIN`, then a `lefthook` on
`PATH` — so a Homebrew lefthook shadowed the pinned 2.1.3. A `rc:
bin/.lefthookrc` (a lefthook config key `lefthook install` bakes into
every dispatcher) exports `LEFTHOOK_BIN` to `bin/lefthook`, so a push
runs the pinned version regardless of `PATH`. `just hooks` already runs
`lefthook install`, so re-running it picks up the `rc` line — no recipe
change needed.

`AGENTS.md` documents that lanes are scoped by merge-base diff and that
agent shells should lead `PATH` with `./bin` so pinned tools win.

## Verification

Reproduced both bugs in a scratch repo mirroring the worktree +
stale-remote topology, with lanes stubbed to echo on selection:

- **Bug 1:** relay-only branch, `git merge origin/main` (main carried
`mobile/` + `desktop/` changes). Without the fix, `desktop-check` and
`mobile-checks` fired; with it, three-dot diff = only the relay file,
all globbed lanes skip.
- **Bug 2:** brand-new branch, no upstream, in a linked worktree with an
alphabetically-first stale remote. Confirmed `@{push}` is `fatal`,
`refs/remotes/origin/HEAD` is absent from the worktree git-dir, and the
stale remote's `HEAD ->` sorts first. Without the fix it fired lanes off
the stale tip; with it, lanes scope to `origin/main` merge-base and
skip.
- **Positive controls:** a `mobile/**` commit still fires
`mobile-checks`; a `crates/**` commit still fires `rust-tests` +
`desktop-tauri-checks`.
- **Dispatch:** with Homebrew lefthook 2.1.10 on `PATH`, running the
real generated `.git/hooks/pre-push` under `LEFTHOOK_VERBOSE=1` shows it
sourcing `bin/.lefthookrc`, exporting `LEFTHOOK_BIN`, and running
`lefthook v2.1.3`.
- This PR's own push (a brand-new branch in a linked worktree — the bug
2 case) ran only `branch-skew` and `file-size-check`; no
mobile/desktop/rust lanes fired, since the branch touches only
`lefthook.yml`, `AGENTS.md`, and `bin/.lefthookrc`.

---------

Signed-off-by: Will Pfleger <pfleger.will@gmail.com>
Signed-off-by: Duncan <dcfd242e557282d7a1e2cf2e6877522682f1e5c6156dc92ca7d90eaedd3b0f95@buzz.block.builderlab.xyz>
Co-authored-by: Duncan <dcfd242e557282d7a1e2cf2e6877522682f1e5c6156dc92ca7d90eaedd3b0f95@buzz.block.builderlab.xyz>
2026-08-20 15:55:00 -04:00
..
2026-03-09 13:02:11 -07:00
2026-03-09 13:02:11 -07:00
2026-03-09 13:02:11 -07:00
2026-03-09 13:02:11 -07:00
2026-03-09 13:02:11 -07:00
2026-03-09 13:02:11 -07:00
2026-03-09 13:02:11 -07:00
2026-04-17 13:13:34 -04:00
2026-03-09 13:02:11 -07:00
2026-04-17 13:13:34 -04:00
2026-04-17 13:13:34 -04:00
2026-04-17 13:13:34 -04:00
2026-04-17 13:13:34 -04:00
2026-03-09 13:02:11 -07:00
2026-03-09 13:02:11 -07:00
2026-03-09 13:02:11 -07:00
2026-03-09 13:02:11 -07:00
2026-03-09 13:02:11 -07:00
2026-03-09 13:02:11 -07:00
2026-03-09 13:02:11 -07:00
2026-03-09 13:02:11 -07:00
2026-03-09 13:02:11 -07:00
2026-03-09 13:02:11 -07:00
2026-03-09 13:02:11 -07:00

Hermit environment

This is a Hermit bin directory.

The symlinks in this directory are managed by Hermit and will automatically download and install Hermit itself as well as packages. These packages are local to this environment.