verify

name	verify
description	Verify await-parallel-limit at its real surface — the npm package boundary (packed tarball installed into a fresh consumer), never via ./src imports.

Verifying await-parallel-limit

Surface: the package boundary. Pack → install into a throwaway consumer → drive as a dependent would.

Recipe

1. Build + pack: npx tsc && npm pack --pack-destination <tmpdir>
2. Fresh consumer: mkdir <tmpdir>/consumer && cd there && npm init -y && npm i <tmpdir>/await-parallel-limit-<ver>.tgz
3. Drive CJS: require('await-parallel-limit').default and named { parallel, settle, map, mapSettled, DEFAULT_CONCURRENCY }.

Flows worth driving

• Legacy dependent shape (@paperbits/core): await parallel(thunks, 30), result discarded.
• Ordering (slow first job must still come back first) and peak-concurrency (active/peak counters in jobs).
• Abort: mid-flight, pre-aborted, synchronous abort from inside a job during startup (regression: must reject, not fulfill with holes), abort after completion (no-op), one signal reused across 30 runs (no MaxListeners warning).
• Fail-fast: after first rejection, started-count must not grow (remaining jobs abandoned).
• Garbage: non-array, junk limits (0, -1, 2.5, NaN, string, null → default 5), non-function array element (TypeError rejection), sparse arrays through map (holes → mapper gets undefined).
• TS surface: compile a consumer .ts against the installed d.ts. Floor is TS 3.4 (readonly I[] in map/mapSettled signatures) — pin with npm i --no-save typescript@3.4.5.

Gotchas

• Node ESM default import works via the exports map + esm/index.mjs wrapper. If import parallel from ever yields an object instead of a function, the exports map or wrapper broke — run test/boundary/smoke.mjs against the packed tarball.
• tsc ... | head masks the exit code — check $? on the tsc command itself, not the pipe.
• Scale check: 100k-item map should be O(10ms); if it regresses to O(100ms), per-item thunk allocation crept back in.