pre-push dynamic check pair (guard-liveness, cmd-script-liveness)

Status: shipped-beta · Ships to: npm-lane consumers — copied by the same installer loop as the static trio (setup.d/50-hooks.sh:33-34) · Fires at: every git push, on the sections of the TS-core pre-push gate where the changed-file set makes them relevant.

What it is

Two change-scoped liveness checks that pre-push.ts loads lazily via await import() rather than static import: checks/guard-liveness.ts (runs the ESLint roundtrip over changed manifest rules to prove the guard catches its violation) and checks/cmd-script-liveness.ts (the same liveness proof for command/script-type manifest rules). Lazy loading is deliberate — these modules pull the ESLint stack, which needs a root-level workspace install the shipped consumer graph does not include.

How it works

guard-liveness.ts "Reuses the ESLint roundtrip logic from validator/gate-rule-tester.ts" and covers "the rules-as-tests namespace from both packages" — core (R2/R7/R8) and preset-next-15-canonical (R12/R14/R20) (packages/core/hooks/checks/guard-liveness.ts:12-19). "Rules using unavailable plugins (R5 @typescript-eslint, R15 jsx-a11y, R16 @next/next) are skipped with a visible SKIP notice — not failures" (:21-23). The pre-push section imports the gate, and on load failure calls die(...) — "❌ guard-liveness: failed to load the ESLint stack — the gate requires a root-level workspace install" (packages/core/hooks/pre-push.ts:519-525). The section header states the contract plainly: "resolution failure here is a loud die, never a silent pass" (:515).

cmd-script-liveness.ts closes "the liveness gap for check.type ∈ {command, script} manifest rules" (packages/core/hooks/checks/cmd-script-liveness.ts:4-5); liveness mode is "DERIVED from check.type by default" (command → run-and-assert, script → resolve-and-run) with an optional manifest liveness-mode override, and "the mode rides IN the manifest … NO rule-id→mode map is hard-coded in this runner" (:9-16). Its honesty contract: the check "must exit 0 on the CLEAN pre-fixture state AND non-zero on the violating fixture to pass"; a check that cannot run in this environment "is SKIPPED … NEVER force-passed" (:18-28).

Fail mode / which channel fails: two distinct channels, both ending the push. (1) Missing module graph (e.g. the consumer never ran a root npm install, or the eslint-rules barrel didn't ship) → die() at import time → non-zero exit → push blocked (pre-push.ts:521-526, :585-588). (2) The check ran and caught a non-live guard → failure report → non-zero exit → push blocked. Skips (unavailable plugin, unavailable binary, clean-state crash) and EXEMPT verdicts are ℹ/⚠ notices that do NOT block — "this distinguishes 'guard caught the violation' from 'script crashed before evaluating it'" (cmd-script-liveness.ts:24-26).

Satellites & companions

Part of the D24b-shipped import graph; the installer comment notes the eslint-rules barrel (F43 territory) must ship too or "guard-liveness.ts die()/push-blocks on load even after the 3 checks above ship" (setup.d/50-hooks.sh:37-39); static siblings are the check trio (D23); @dual-pair: guard-liveness-eslint pairs the TS gate with its portable form (guard-liveness.ts:8).

Anchors

• setup.d/50-hooks.sh:33 — « checks/guard-liveness.ts \» (pair at :33-34)
• setup.d/50-hooks.sh:38 — «# ../../eslint-rules/index.ts). Without this group, guard-liveness.ts die()/push-blocks»
• packages/core/hooks/checks/guard-liveness.ts:4 — « * Channel: pre-push (liveness — runs ESLint roundtrip).»
• packages/core/hooks/checks/guard-liveness.ts:21 — « * Rules using unavailable plugins (R5 @typescript-eslint, R15 jsx-a11y, R16 @next/next)»
• packages/core/hooks/checks/cmd-script-liveness.ts:4 — « * Closes the liveness gap for check.type ∈ {command, script} manifest rules — the»
• packages/core/hooks/checks/cmd-script-liveness.ts:22 — « * exit 0 on the CLEAN pre-fixture state AND non-zero on the violating fixture to»
• packages/core/hooks/pre-push.ts:515 — « // resolution failure here is a loud die, never a silent pass — the gate only»
• packages/core/hooks/pre-push.ts:519 — « gate = await import('./checks/guard-liveness.ts');»
• packages/core/hooks/pre-push.ts:583 — « gate = await import('./checks/cmd-script-liveness.ts');»