The hollow audit fits a 512 MiB check runner: it collects each file's syntax tree as it goes, and the command's test runs in its own process #44

Stacked on fix/ci-fork-pr-checkout (#40): its commit is in this diff until it merges.

On main's check, test/hollow.test.ts was the gate's most frequent red: shard 2 OOM-killed at it twice (runs 874 and 883, exit 137 with memory.current pinned at memory.max 512 MiB) and once swapped until "bun scripts/hollow.ts says so and exits 0" took 450 s against its 60 s timeout (run 859; spawnSync blocked the timer).

Two causes, both fixed without touching what the tests assert:

• scripts/hollow.ts parses 838 files with the TypeScript API and dropped each

tree as garbage, but nothing collected it, so one audit peaked at ~442 MiB RSS for ~20 MiB of live heap. It now runs a full collection every 64 files: ~270 MiB peak, same result, no measurable time cost.

• The command's test spawned a second whole-tree audit beside the test

process's own two audits. It moves to test/hollow-cli.test.ts, whose process audits nothing itself, and awaits Bun.spawn so its timeout can end a stuck child. The guard test now keeps both files out of EXCLUDED.

Peak memory of the whole process tree (PSS summed over test-shards, bun test and the child, sampled every 50 ms), bun 1.3.14, FORGE_CHECK_SHARDS=1: test/hollow.test.ts on main 504 MiB of the runner's 512; after, 276 MiB for test/hollow.test.ts and 257 MiB for test/hollow-cli.test.ts. The audit alone: ~442 MiB RSS before, ~270 MiB after.

Evidence

pipeline/status keeps one main event per finished push gate. Over the last 37 runs main was green in 22 (59%). test/hollow.test.ts is its most frequent single cause: OOM-killed in gate shard 2 in runs 874 and 883 (shard 20/160 done (exit 137), mem_current=536870912), and swapped until it timed out in run 859 ("bun scripts/hollow.ts says so and exits 0" timed out after 60000ms, 449,848 ms elapsed).

Not loosened

No assertion, timeout or exclusion changes. The command's test moves to its own file unchanged, apart from Bun.spawn + await replacing spawnSync, so its 60 s timeout can fire.

Validation note

The fast tier's other reds are not this change. They show up in the table below as FLAKY or BASELINE:

• vitals "errors are counted…" and tui-sentinel "an admin has it…" fail only beside test/drill-board-line.test.ts in one process. That file leaks a notifier pager, fixed on branch fix/tests-close-notifiers.
• contain "an undeclared public host…" fails only on the validation box, whose DNS returns 198.18.x.
• following, tui-workflows and usage-count pass when run alone on this branch: FLAKY, cause not diagnosed yet.
• Gate (2) stopped at following (fail-fast) before reaching the hollow files. The same commit's earlier validation, before it was stacked on #40 (9d3fe1f6, which differs only in the workflow files), ran gate (2) green through test/hollow.test.ts and test/hollow-cli.test.ts.

<!-- pipeline:validation -->

Validation

pipeline/validate on bc87716f: flaky in 476s — bun 1.3.14, CI-shaped env (scrubbed vars, runner PATH), exact check.yml shard + forge.json commands.

• ⚠️ node v20.19.2 here, v22 on CI (tsc runs under node)
• ⚠️ check.yml gate (1) pull_request stopped early at a BASELINE failure (fail-fast): its later files were not run in this step
• ⚠️ check.yml gate (2) pull_request stopped early at a FLAKY failure (fail-fast): its later files were not run in this step

▶ bun install --frozen-lockfile
  ok  exit 0  0s
▶ forge.json check.fast
(fail) the sentinel command > an admin has it, and it says what the board says [16.23ms] [shard 1]
(fail) egress, reported: an undeclared public host goes through and is counted; a private one never does > an undeclared public host is let through and counted [0.89ms] [shard 10]
Ran 3064 tests across 303 files in 103.8s; 2 failed.
classify: reran test/contain.test.ts test/tui-sentinel.test.ts test/tui-workflows.test.ts test/usage-count.test.ts  alone on origin/main 1051d451 and on this branch
classify: not red on main:
  FLAKY  exit 1  110s
▶ check.yml gate (1) pull_request
(fail) egress, reported: an undeclared public host goes through and is counted; a private one never does > an undeclared public host is let through and counted [1.74ms] [shard 3]
Ran 110 tests across 3 files in 20.7s; 1 failed.
classify: reran test/contain.test.ts  alone on origin/main 1051d451 and on this branch
  BASELINE  exit 1  22s
▶ check.yml gate (2) pull_request
(fail) a fork that follows its parent > a proposal names only what is actually ahead: work the parent already has is not listed again [654.26ms] [shard 3]
Ran 61 tests across 3 files in 23.8s; 1 failed.
classify: reran test/following.test.ts  alone on origin/main 1051d451 and on this branch
classify: not red on main:
  FLAKY  exit 1  27s
▶ check.yml gate (3) pull_request
Ran 1721 tests across 165 files in 317.2s (165 shards).
  ok  exit 0  317s