* build: scripts/gate — a target dir per worktree, and one gate suite
Parallel worktrees do not work on this machine, and the reason is one
exported variable: every checkout builds into one CARGO_TARGET_DIR, and
cargo takes an EXCLUSIVE LOCK on it. Two lanes building at once do not
run in parallel — the second blocks — and they invalidate each other's
artifacts, so alternating between them recompiles from scratch. Parallel
development under that arrangement is slower than serial.
MEASURED, BECAUSE THE FIRST PLAN WAS WRONG. The shared directory is
285G, which drove a proposal to add sccache so per-worktree directories
would not lose artifact sharing. That number is years of accumulation
across TWO projects (pmacs and levcs share it). Measured directly: a
cold `cargo test --workspace --no-run` is 80s and 19G. And sccache
across two target directories hits 50% on C/C++ and **0.00% on Rust** —
rlibs embed their target-dir path, so dependency artifacts are not
bit-identical between directories and `--extern` hashes cascade into
misses. There is no sharing worth buying back. sccache stays configured
and earns its keep on C/C++; it is not what makes parallel lanes work.
The script also owns the FIXED gates, because a procedure living only in
prose gets executed differently each time — twice in the session that
motivated this:
- a sweep run with `--tests` instead of `--workspace`, silently
dropping pmacs_protocol and pmacs_gpu, including protocol tests that
same lane had just written;
- a sweep piped through `grep` before anyone read it, so an
intermittent red could not be matched against ci-red-signatures —
a row needs its fragments. That is registry note U2, and then U3
when it happened AGAIN.
Hence durable per-gate logs with the sweep paths printed. The remedy is
real: this lane's own run diagnosed its failures from the log without
re-running anything.
WHAT THE SCRIPT IS NOT AUTHORITATIVE FOR. Handoff §3 keeps policy and
keeps CHOOSING the touched acceptance suites, which arrive only via
`--acceptance`. No script can infer those from a working tree, and one
that guessed would report coverage it does not have.
THREE HAZARDS SPECIFIED RATHER THAN LEFT TO CHANCE:
- `cmd | tee log` reports TEE's status, so a failing gate would exit 0
and the suite would read green. `pipefail` is not POSIX.
- `cmd > log; rc=$?` never reaches the assignment under `set -eu`
(which scripts/bite already uses) — the shell exits at the failing
command, so nothing prints which gate failed or where its log is,
destroying the point of capturing it. The runner is therefore an
`if` condition, the only `set -e` exemption.
- CARGO_TARGET_DIR (env) OVERRIDES build.target-dir in config.toml, so
a per-worktree config file silently does nothing. Only a
per-invocation value beats it.
Pruning is dry-run by default, `--force` to delete, and refuses any
directory without a `.pmacs-gate-target` marker. "Live" means a git
worktree record carrying NO `prunable` line — git keeps listing a
worktree whose directory was deleted without `git worktree remove`, and
treating listed as live would make exactly the reclaimable directories
permanently ineligible.
ONE HONEST FINDING FROM MUTATION TESTING. Three mutations came back
vacuous, and all three are redundant defences rather than test holes:
git already returns resolved physical paths from both
`rev-parse --show-toplevel` and `worktree list --porcelain`, so canon()
is belt-and-braces; and the prune path guards the marker twice. Recorded
in the script and the tests so a later reader does not mistake a
"vacuous" result for a gap — or delete a defence because a test did not
notice.
VERIFICATION. 11 acceptance tests over the no-gates paths (running the
script for real inside the suite would recurse), each pointed at a
tempdir via PMACS_GATE_TARGET_ROOT so the real managed root is
unreachable — a prune bug is unrecoverable. Mutation-tested: `--tests`
in the sweep, an unconditional CRDT sweep, and pruning on a dry run all
fail their intended test.
Observed in a real run, which is how the framing said to confirm the
parts a test cannot: the failed-gate names and log paths print, the
ambient directory is created and reaped by the exit trap, and every log
appears. The run exits non-zero because of R8 — the pre-existing,
merge-base-confirmed listview failure — which means `scripts/gate`
cannot go green on this machine until R8 is diagnosed. That is a
property of the tree, not of this change.
Framing: docs/gate-script-framing.md (revision 4, approved).
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016bqGA6s9tTUFzYpbeW3tai
* fix(gate): two ways the script could do harm, and four smaller defects
Review round 1 on #225. Neither blocking finding was a design gap ---
both were the implementation failing to honour its own framing, which
is the case a framing document cannot prevent by itself.
PRUNE COULD DELETE EVERY MANAGED DIRECTORY. §2.6 requires the live
worktree set to be ESTABLISHED. The code piped `git worktree list`
straight into awk and the caller masked the result with `|| true`, so
running from outside any repository produced an EMPTY live set --- and
an empty live set means "every managed directory is an orphan", so
`--prune --force` would have deleted all of them, live lanes' artifacts
included. The failure mode was silent and total.
Two refusals now, and they are deliberately redundant: not inside a
worktree, and the enumeration itself failing. `live_worktrees` captures
git's output and returns non-zero rather than emitting nothing, so
"I cannot tell what is live" is unrepresentable as "nothing is live".
An empty porcelain listing counts as failure too --- a repository always
has at least its own worktree.
--ACCEPTANCE WAS SHELL-INJECTABLE. The name is interpolated into a
command the runner evaluates, and nothing validated it, so
`--acceptance 'x; rm -rf ~'` would have run. Now an allowlist of what a
cargo test target can actually be named --- letters, digits, underscore,
hyphen --- refused at parse time, before any gate. Rejection rather than
escaping: there is no legitimate suite name that needs quoting.
FOUR SMALLER ONES:
- Log directories carried a whole-second timestamp, so two runs in the
same worktree within one second shared one and could overwrite each
other's evidence --- reintroducing U2/U3 through a naming choice.
The PID is now part of the name.
- The ownership marker is DOCUMENTED as one line, so it is enforced as
one line instead of read head-first. Acting on the first line of a
file we did not understand is how a corrupted marker authorises a
deletion.
- The `prunable` test returned green when `git worktree add` failed,
so the only coverage of that rule could silently never run. It now
fails loudly.
- Its cleanup ran after the assertions, so a panicking assertion would
have left the real repository carrying a stale worktree record. Now
a `Drop` guard.
MUTATION TESTING, HONESTLY REPORTED. The injection and marker fixes bite
individually. The two prune guards do NOT --- each alone satisfies the
outside-repo test, so mutating one at a time reads as vacuous. Removing
BOTH fails the test, which is what establishes that the test detects the
unsafe state rather than being blind to it. Recorded in the test so a
later reader does not delete one guard on the grounds that nothing
noticed.
ALSO: handoff §3's ambient-root caveat still said "until the
ambient-root isolation lane lands". #206 merged; the five variables are
now belt-and-braces for external and integration paths, and `scripts/gate`
sets them regardless.
R8 PROMOTED. `docs/ci-red-signatures.md` gains the reason it stops being
a catalogued curiosity: with the gate suite reduced to one command, R8
makes that command exit non-zero on a clean tree EVERY TIME, and a gate
that is always red is a gate nobody reads. `docs/active-work.md` gains a
lane. It is still not a regression from #223 or #225 --- the merge-base
control says so --- and the lane's first job is diagnosis, because a
change that made the assertion pass without explaining the prefix strip
would convert a visible failure into an invisible one.
15 acceptance tests. Observed run re-confirmed: failed gates named with
log paths, ambient directory created and reaped, distinct log directory,
exit 1 from R8 alone.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016bqGA6s9tTUFzYpbeW3tai
* docs: the #225 lane, and R8 diagnosed to a stray /tmp/.git
TWO LEDGER GAPS, both found by review.
and — the part that matters — an explicit GATE STATUS: NOT GREEN
section. `scripts/gate` exits 1 on this branch and on a clean `main`
because R8 fails m4_acceptance and therefore the sweep. That is a merge
blocker under the standing rule, and #225 is the worst possible lane to
grant a silent exception to: it is the lane that makes the gate suite
authoritative, and a tool shipping with its own gate red teaches the
opposite of what it exists to teach.
The lane also records that it was written after the PR existed, again,
because review asked again. Two lanes in a row now. The correction from
only evidence of that.
R8 DIAGNOSED, and the `TMPDIR` hypothesis was right:
1. `display_path` (builtin/runtime/lsp.lua:2397) shortens a location
against the DETECTED PROJECT ROOT before rendering it.
2. `project.detect` walks UPWARD for a marker; from
/tmp/.tmpXXXX/r.rs it reaches /tmp.
3. This machine has a stray `/tmp/.git` — an EMPTY DIRECTORY, not a
repository. The `.git` marker is directory-only, so an empty
directory still matches.
4. Root resolves to /tmp, the prefix is stripped, and the rendered row
is exactly the observed `.tmpXXXXXX/r.rs:12:3`.
Controlled, not inferred: the same test with TMPDIR outside /tmp PASSES.
THE CODEBASE ANTICIPATED THIS BY NAME. src/project.rs:208 documents
`detect_project_within(start, markers, stop_root)` as existing "so a
stray marker in a temp-dir's ancestor (e.g. a developer's /tmp/.git)
can't leak into a fixture that lives below it." The mechanism exists;
this fixture does not use it.
So the row splits, and the halves need different fixes. The failure is
ENVIRONMENTAL — nothing about pmacs is wrong when a real project root
sits above a file, that is the feature, and removing /tmp/.git makes the
gate green immediately. The fixture being ENVIRONMENT-DEPENDENT is a
real defect, and bounding its detection is what retires the row.
PROVENANCE UNRESOLVED, and I am not going to assume in my own favour:
/tmp/.git is dated 2026-08-07 23:17, inside this session's window, and
may have been created by this session's own work — a stray git
invocation from /tmp would do it. The earlier merge-base control stays
valid as "this tree has it" but says nothing about WHEN the environment
acquired the marker, so "pre-existing" must not be read as
"long-standing".
Nothing deleted: /tmp/.git is outside the repository and I cannot
confirm I created it, so removing it is the user's call.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016bqGA6s9tTUFzYpbeW3tai
* docs: rebase onto the R8 fix; scripts/gate now exits 0
#226 (`dcb852e`) retired R8 by bounding the LSP fixture's project
detection. This branch rebases onto it, and the thing that was blocked
is now demonstrable: **`scripts/gate` exits 0** --- all nine gates green
in one command, the first time the tool has passed the suite it exists
to run. That is #225's own acceptance criterion, and it could not even
be stated while the script did not exist on `main`.
REBASE RESOLUTION, per the standing rule that #226's R8 documentation is
authoritative. Every conflict was in R8 text this branch wrote while the
row was still an open investigation:
- two in `docs/ci-red-signatures.md`, both resolved to #226's retired
row with this branch's pre-fix copy dropped;
- the framing-doc pair --- e71e1bd added `docs/r8-fixture-boundary-
framing.md`, 7cfba73 removed it --- both SKIPPED. They are net-zero
here and `main` owns that file authoritatively; replaying the second
would have deleted `main`'s copy, which is the one failure mode a
mechanical "resolve each conflict in turn" would have walked into.
TWO STALE LANES REMOVED. This branch's "R8 --- NEEDS A LANE"
investigation block describes a diagnosis that has since happened and a
fix that has since landed. And #226's own lane arrived through the
rebase still saying "OPEN, HELD FOR REVIEW"; Rule 4 retires it now that
it has merged, its durable facts already being in the retired registry
row and the handoff section 6 census. Leaving either would have left the
ledger asserting that a merged fix was still an open investigation.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016bqGA6s9tTUFzYpbeW3tai
---------
Co-authored-by: Claude Opus 5 (1M context) <noreply@anthropic.com>
Levi Neuwirth
4bc55e8dd2