fusion/packages/engine/vitest.config.ts

import { defineConfig } from "vitest/config";
import { resolve } from "node:path";
import { computeMaxWorkers } from "../core/src/__test-utils__/vitest-workers";

const maxWorkers = computeMaxWorkers();

export default defineConfig({
  resolve: {
    alias: {
      /*
      FNXC:VitestAliases 2026-07-30-13:10:
      Must precede the broader `@fusion/core` alias: Vite string aliases match by PREFIX, so that key
      rewrites this subpath to `index.ts/task-delete-attribution` and resolution fails. Reached here
      transitively — this project aliases `@fusion/dashboard`, and `app/api/client.ts` imports the
      browser-safe delete-attribution leaf.
      */
      "@fusion/core/column-roles": resolve(__dirname, "../core/src/column-roles.ts"),
      "@fusion/core/task-delete-attribution": resolve(__dirname, "../core/src/task-delete-attribution.ts"),
      // FNXC:MemoryMcp 2026-08-11-00:19: Preserve the Node-only factory subpath without leaking it through the browser-safe core barrel.
      "@fusion/core/mcp-builtin-servers": resolve(__dirname, "../core/src/config/mcp-builtin-servers.ts"),
      "@fusion/core": resolve(__dirname, "../core/src/index.ts"),
      "@fusion/test-utils": resolve(__dirname, "../core/src/__test-utils__/workspace.ts"),
      "@fusion/engine": resolve(__dirname, "./src/index.ts"),
      "@fusion/plugin-sdk": resolve(__dirname, "../plugin-sdk/src/index.ts"),
      "@fusion/dashboard": resolve(__dirname, "../dashboard/src/index.ts"),
    },
  },
  test: {
    setupFiles: [
      resolve(__dirname, "../core/src/__test-utils__/vitest-setup.ts"),
    ],
    globalSetup: [resolve(__dirname, "../core/src/__test-utils__/vitest-teardown.ts")],
    // Keep the broad engine lanes on worker threads; engine-core overrides this
    // below because only the curated merge gate has hit the Node/macOS abort.
    pool: "threads",
    maxWorkers,
    minWorkers: 1,
    fileParallelism: true,
    // Enable isolate to allow parallel execution of tests with conflicting mocks
    isolate: true,
    // Engine real-git tests spawn many subprocesses; under full-suite concurrent
    // load even 60 s can fire prematurely. Bump to 120 s — the guard only fires
    // on hangs, so healthy tests pay nothing.
    env: {
      FUSION_TEST_SUBPROCESS_TIMEOUT_MS: "120000",
    },
    // Real-git integration tests need more than the default 5 s under concurrent
    // load (other packages run tests at the same time via pnpm recursive).
    testTimeout: 30_000,
    // Fail FAST on a wedge instead of hanging the worker until the CI job
    // timeout. A real-git test can leave a promise (e.g. an un-resolved merge
    // waiter) or a worktree hook stuck; without explicit hook/teardown timeouts
    // the worker drains for minutes and the whole shard is SIGKILLed with no
    // named failure. These bound setup/teardown so the culprit test is reported.
    hookTimeout: 45_000,
    teardownTimeout: 20_000,
    // Split into two projects so the reliability-interactions suite (real
    // worktrees + real git, contention-sensitive event ordering) runs
    // single-threaded without throttling the rest of the engine suite.
    // Keep include globs project-scoped (not at root) so engine-reliability
    // does not inherit full-suite include and rerun everything single-threaded
    // (FN-5537: this caused long runs and external SIGTERM 143 kills).
    projects: [
      {
        extends: true,
        resolve: {
          /*
          FNXC:EngineTests 2026-07-08-03:00:
          FN-7667: scope the gate-safe @fusion/core barrel (packages/core/src/index.gate.ts)
          to THIS project only. It must not leak to the root resolve.alias — that would
          silently narrow the module graph for engine-default/engine-reliability/engine-slow
          too. Project-level resolve.alias merges over (does not replace) the root map
          inherited via extends:true, so @fusion/test-utils/@fusion/plugin-sdk/@fusion/dashboard
          stay on their root aliases and only @fusion/core is overridden here.

          FNXC:MergeGatePerformance 2026-08-04-15:44:
          FN-8783 confirms W32's engine-core lane has 22 exact policy files.
          The current core bundle remains the only evidence-backed import-path
          optimization: it is rebuilt every run, retains mock interception, and
          avoids the measured-slower engine-graph bundle designs below. Keep pool,
          worker budgeting, file parallelism, and this alias intact; membership is
          pinned in scripts/__tests__/engine-vitest-gate-policy.test.mjs.

          FNXC:EngineTests 2026-07-08-04:50:
          FN-7669: the @fusion/core alias now points at a PRE-BUNDLED single ESM
          file (packages/core/.gate-bundle/core.mjs — a SIBLING of
          packages/core/node_modules/, deliberately NOT nested inside it; nesting
          inside node_modules triggers Vite's SSR external-dep heuristic and
          silently defeats vi.mock interception for imports nested inside the
          bundle, see scripts/build-engine-core-gate-bundle.mjs for the full repro)
          instead of directly at index.gate.ts's source. FN-7668 profiled the
          gate's dominant wall-time cost as vitest/Vite SSR's import-phase — each
          of the fork workers independently re-resolving+evaluating the ~430-file
          barrel closure with zero cross-fork sharing. esbuild-
          bundling the index.gate.ts closure (220 first-party files, the
          @fusion/core slice of that ~430) into one file
          (scripts/build-engine-core-gate-bundle.mjs, wired below via globalSetup
          so it is rebuilt fresh before every gate invocation — never a hand-
          maintained/stale artifact) collapses that to a single file load per
          fork. See the task's docs document for the full A/B measurement,
          coverage-parity proof, and land/no-land rationale.
          @fusion/engine is deliberately left on the full barrel, unbundled: none
          of the originally profiled curated files imported "@fusion/engine" at
          all, so bundling it would be zero-benefit
          churn/risk — and it would additionally risk double-registering or
          dead-locking the core↔engine circular-import DI
          (`void import("@fusion/core").then(setCreateFnAgent...)` in
          packages/engine/src/index.ts) for no measured gain.

          FNXC:EngineTests 2026-07-08-06:20:
          FN-7670 prototyped extending this same lever to the @fusion/engine
          RELATIVE-import production graph (`../merger.js`, `../hold-release.js`,
          `../scheduler.js`, `../workflow-node-handlers.js`, ...) that curated gate
          files reach directly — NOT the barrel above, which stays untouched per
          the paragraph above regardless. It built a fully working, coverage-
          parity-preserving, mock-safe bundle (171 first-party files → 35 output
          files via esbuild multi-entry splitting) but an interleaved, host-load-
          controlled A/B showed NO clear incremental wall-time win over this
          @fusion/core-only bundle (delta within this host's own ~2.5x run-to-run
          noise band) — the byte-size growth of 14 separate large root bundles
          (e.g. one alone reached 1.3MB) offset the per-file-dispatch savings that
          made the single-file @fusion/core bundle above pay off. NOT landed; the
          wiring was reverted to this @fusion/core-only state. See FN-7670's task
          docs document for the full closure/mock-boundary analysis, the A/B
          methodology and data, and the negative-result rationale.

          FNXC:EngineTests 2026-07-08-06:20:
          FN-7673 re-attempted this lever with a SINGLE COMBINED-ENTRY design
          (all 14 mock-safe roots redirected via a resolveId plugin to ONE
          packages/engine/.gate-bundle/engine.mjs, no `splitting`, mirroring the
          @fusion/core bundle's one-alias/one-output-file shape) rather than
          FN-7670's 14-separate-root design. It achieved the design goal (149
          first-party inputs -> 1 output file) and full coverage parity (335/335)
          but a TRUE interleaved A/B (5 warm pairs + 1 cold pair) showed the
          combined-entry bundle is CONSISTENTLY SLOWER than this @fusion/core-only
          baseline — warm median real +29.1% slower, import-phase aggregate
          +74.0% slower, holding across every pair (not within this host's noise
          band, unlike FN-7670's inconclusive result). Working theory: funnelling
          all 14 original relative-import sites through a `resolveId`-plugin
          redirect to one large (2.3MB) synthetic `export *` file adds more
          transform/resolution overhead than it saves, unlike the @fusion/core
          bundle's plain `resolve.alias` (a single fixed target, no per-specifier
          plugin hook). NOT landed; wiring fully reverted to this @fusion/core-
          only state (both the engine-graph scans and the combined-entry builder
          were removed from scripts/build-engine-core-gate-bundle.mjs, and the
          resolveId plugin was removed from this file — full diff in FN-7673's
          git history). This lever (bundling the @fusion/engine relative-import
          graph for the engine-core gate, in either a 14-file or single-combined-
          entry shape) is now considered CLOSED — do not re-attempt without new
          evidence changing the underlying cost model. See FN-7673's task docs
          document for the full A/B data, the mock-boundary risk finding (a
          combined-entry design broke a shared-test-helper vi.mock in a way
          FN-7670's per-root design never could), and the closure rationale.
          */
          alias: {
            "@fusion/core": resolve(__dirname, "../core/.gate-bundle/core.mjs"),
          },
        },
        test: {
          name: "engine-core",
          /*
          FNXC:EngineTests 2026-07-08-04:50:
          FN-7669: prepend the gate-bundle builder to this project's globalSetup so
          the @fusion/core bundle above is rebuilt before fork workers spawn and
          resolve the alias. REBUILD-EVERY-RUN is the invalidation model — the
          builder's own esbuild dependency graph (not a hand list) determines what
          gets bundled, and because it reruns on every gate invocation there is no
          drift surface. The original root-level vitest-teardown.ts worker-root
          cleanup hook is preserved (both entries run; order does not matter, they
          are independent) rather than replaced, since `extends:true` does not
          array-merge test.globalSetup across project/root the way resolve.alias
          object-merges.
          */
          globalSetup: [
            resolve(__dirname, "../core/src/__test-utils__/vitest-teardown.ts"),
            resolve(__dirname, "../../scripts/build-engine-core-gate-bundle.mjs"),
          ],
          /*
          FNXC:EngineTests 2026-06-25-11:11:
          The curated engine-core merge gate hits a Node 24.15.0/macOS libuv kqueue SIGABRT when Vitest thread workers close unmanaged file descriptors. Scope fork workers to this gate so the broad default engine suite keeps its explicit worker-thread behavior.
          */
          pool: "forks",
          experimental: {
            /*
            FNXC:MergeGatePerformance 2026-08-04-16:09:
            FN-8783 retains all 22 forked files but enables Vitest's validated
            filesystem transform cache only for engine-core. Fork isolation still
            evaluates every test and preserves mocks; caching immutable Vite
            transforms avoids repeating import/setup compilation on warm gate runs.
            Keep this cache project-scoped so broad engine lanes cannot inherit
            gate-specific artifacts, and let Vitest invalidate entries from its
            transform dependency graph rather than maintaining an unsafe file list.
            */
            fsModuleCache: true,
            fsModuleCachePath: resolve(__dirname, "node_modules/.engine-core-fs-module-cache"),
          },
          // The curated merge-gate suite (see docs/testing.md "Merge gate").
          // Membership is an explicit allow-list, NOT a glob: tests earn their
          // way in with evidence of value, and a flaky gate test is evicted by
          // deleting its line here (no need for the flaky test to pass).
          // Selection criteria: deterministic (no real git subprocesses, no
          // real timers/network), fast (<~3s/file per scripts/test-timings.json),
          // covering regression-prone core invariants: merge lifecycle and
          // scope, files-changed/fork-point attribution, executor core paths,
          // triage, scheduling, self-healing.
          // Budget: the whole project must stay under ~60s wall-clock so the
          // CI gate job's test run lands under ~1 minute.
          /*
          FNXC:EngineTests 2026-07-08-00:00:
          Removed merger-post-merge.test.ts — retired by FN-7039 (graph is sole post-merge owner); it matched zero files. Graph post-merge is covered by workflow-graph-post-merge.test.ts in engine-default; no gate replacement needed.
          */
          include: [
            /*
            FNXC:EngineTests 2026-07-31-00:40 (PR #2557 review — greptile):
            THE CENSUS RATCHET MUST BE IN THE BLOCKING GATE, or it cannot do the one
            thing it exists for. Outside the gate a PR can add a legacy column
            comparison and every blocking check stays green while the count rises —
            the ratchet notices hours later in a non-blocking run, which is exactly
            the window this program kept losing work in.

            Admission evidence: it is pure computation over `git ls-files` plus file
            reads — no store, no network, no timers, no subprocess beyond one
            `ls-files`. Measured ~0.3s. Deterministic by construction: same tree,
            same number.
            */
            "src/__tests__/legacy-column-literal-census.test.ts",
            /*
            FNXC:EngineTests 2026-07-31-23:59:
            THE MOVE-TARGET RATCHET BELONGS HERE FOR THE SAME REASON THE CENSUS RATCHET ABOVE DOES,
            and the argument is stronger for this one.

            The census counts COMPARISONS; a move target is an ARGUMENT, so nothing above sees it. And
            the failure mode is harder than a stale guard's: `moveTaskInternal` REJECTS a target the
            workflow does not declare (`TransitionRejectionError: unknown-column`), so a regression
            here THROWS on a renamed board instead of degrading — in recovery paths, which are the
            ones that run when something has already gone wrong.

            Outside the gate this repeats the pattern this program keeps paying for: a correct signal
            that fires in a non-blocking run while the PR merges anyway. That happened to my own
            #3114 this week — `check-inert-sync-lanes` flagged it correctly and it landed regardless.

            Admission evidence, on the same terms as the entries around it: pure computation over one
            `git ls-files` plus file reads. No store, no network, no timers, no subprocess beyond that
            one call. Deterministic by construction — same tree, same counts. Measured 509ms / 508ms
            across runs, 12 tests, after memoising the corpus scan (it was 800ms when each case
            re-read every file).
            */
            "src/__tests__/no-legacy-move-targets.test.ts",
            "src/__tests__/merger-merge-lifecycle.test.ts",
            "src/__tests__/merger-conflict-resolution.test.ts",
            "src/__tests__/merger-diff-scope.test.ts",
            "src/__tests__/merger-landed-files-capture.test.ts",
            "src/__tests__/branch-attribution.test.ts",
            /*
            FNXC:EngineTests 2026-08-10-09:35:
            FN-8937 rescued project-engine.test.ts into engine-default by sealing its
            git resolver seam and using real guard watchdog timers. It remains outside
            engine-core: merge-gate admission requires separate deterministic evidence.
            */
            /*
            FNXC:EngineTests 2026-07-28-21:05 (#2520 review — greptile P1):
            Capacity single-flight IS covered — by this purpose-built file, not by anything in project-engine.test.ts. It was outside blocking CI, which is the real gap. Removing `if (this.mergeRunning) return;` fails "refuses a second concurrent drain while one merge is in flight" here and nowhere else. Deterministic, 3.69s / 3 tests.
            */
            "src/__tests__/merge-single-flight-invariant.test.ts",
            /*
            FNXC:EngineTests 2026-07-29-12:40 (U9 review lane):
            The merge half of U9's safeguards fires in blocking CI; this is the review half, which did not. `workflow-step-verdict-parsing.test.ts` holds the leniency guard: a prose REJECTION must never be promoted to APPROVE. Removing the REVISE/RETHINK/negated-approval disqualifiers in `proseSignalsClearApproval` fails 11 of its cases — a fail-OPEN defect on the path to an irreversible merge, so it belongs in the gate rather than a non-blocking run hours later. Deterministic, pure parser assertions, no mocks/git/network.

            NOT admitted: `reviewer.test.ts`, which holds the sibling "a provider outage is not a review verdict" family. It is green in engine-default but fails 72 cases under engine-core, because that project resolves @fusion/core through the REDUCED `index.gate.ts` barrel/bundle and the suite reaches exports it does not carry (`__vite_ssr_import_0__.has…` TypeError). Admitting it needs the gate barrel widened, which trades away the bundle's whole reason for existing; left outside deliberately rather than papered over.
            */
            "src/__tests__/workflow-step-verdict-parsing.test.ts",
            /*
            FNXC:EngineTests 2026-07-28-10:20:
            Gate admission evidence (U9): this pins which authority actually decides merge-region policy — the built-in IR declares `merge-retry.maxAttempts` / `manual-merge-hold.release` that no handler reads, while the live budgets sit in `settings.maxAutoMergeRetries` and `ProjectEngine.MAX_AUTO_MERGE_TRANSIENT_RETRIES`. Merge is where irreversible work happens, and the drift it guards is SILENT: a handler-only edit can quietly make the dead IR config live (or move the live budget) with no other test failing. Outside the gate the ratchet cannot fire on the defect it exists for. Deterministic and pure — no git subprocesses, no timers, no network, no store; 3 ms of assertions.
            */
            "src/__tests__/u9-merge-region-node-config-authority.test.ts",
            /*
            FNXC:EngineTests 2026-06-23-10:48:
            Workflow columns and workflow graph execution are now the default runtime. Retire the legacy direct-dispatch executor/scheduler gate files and gate the new hold-release plus graph interpreter seams instead.

            FNXC:EngineTests 2026-06-23-23:04:
            The cutover gate must also keep one direct executor recovery guard for graph execute self-requeue preservation. This protects the new marker path after retiring the broad legacy executor recovery gate file.
            */
            "src/__tests__/executor-graph-requeue-gate.test.ts",
            /*
            FNXC:EngineTests 2026-06-25-18:00:
            hold-release.test.ts evicted from the gate: it constructs TaskStore with
            inMemoryDb:false and directly manipulates the SQLite DB via store.db.prepare().
            The SQLite runtime is being removed (delete-sqlite-runtime-final). Per AGENTS.md,
            a flake/gate test that can't pass without the SQLite path is evicted by deleting
            its line from the engine-core allow-list. The hold/release sweep logic is covered
            by PG-backed engine tests.
            */
            /*
            FNXC:EngineTests 2026-06-30-00:00:
            workflow-graph-task-runner.test.ts evicted from the gate: it constructs TaskStore
            with inMemoryDb:true which is removed in the PG cutover. Uses SQLite-only path.
            The workflow graph validation coverage is maintained by workflow-ir.test.ts
            and PG-backed integration tests.
            */
            "src/__tests__/workflow-graph-executor-parity.test.ts",
            /*
            FNXC:EngineTests 2026-06-29-00:00:
            The minimal task-pipeline smoke belongs in engine-core because the default builtin:coding path is now a merge-gate canary: it proves the unselected-task runtime reaches merge with deterministic in-memory seams only, without real git, network, subprocesses, timers, or broad e2e scope.
            */
            "src/__tests__/task-pipeline-smoke.test.ts",
            "src/__tests__/scheduler-workflow-cutover.test.ts",
            "src/__tests__/executor-base-commit-capture.test.ts",
            "src/__tests__/executor-capture-modified-files-attribution.test.ts",
            "src/__tests__/triage-preflight.test.ts",
            "src/__tests__/mission-scheduler.test.ts",
            "src/__tests__/heartbeat-monitor.test.ts",
            "src/__tests__/workflow-node-handlers.test.ts",
            "src/__tests__/workflow-policy-ownership-map.test.ts",
          ],
          // No per-file quarantine excludes needed here: engine-core's
          // membership is the explicit include allow-list above, so any
          // quarantined file (e.g. merger-file-scope-invariant.test.ts) is
          // already absent. The quarantine excludes live in engine-default,
          // whose `src/**/*.test.ts` glob is what would otherwise pick them up.
          exclude: [
            "node_modules/**",
            "dist/**",
          ],
        },
      },
      {
        extends: true,
        test: {
          name: "engine-default",
          include: ["src/**/*.test.ts"],
          exclude: [
            "src/__tests__/reliability-interactions/**/*.test.ts",
            // Real-git heavy files run in the engine-slow project so local
            // `pnpm test` stays snappy. CI picks them up via `test:slow`
            // / `test:all` invoked from the root `test:full` script.
            "src/**/*.slow.test.ts",
            /*
            FNXC:FullSuiteBookkeeping 2026-08-09-03:49:
            All 11 engine-default entries from the 2026-08-05 full-suite quarantine wave (run 30982276306) were deleted under the deletion ratchet after operator directive. These tested pre-refactor APIs (getBuiltinWorkflow removed post-U10b), stale mock shapes, census/allowlist drift, and mock-hoist errors that no longer have a production path to exercise.
            */
            /*
            FNXC:EngineTests 2026-06-26-13:15:
            FN-7068 rescued the 2026-06-25 self-healing quarantine batch by completing the local TaskStore fakes for the FN-5488 overlap path. Keep both files active in engine-default so fake drift around clearStaleBlockedBy() is caught before the deletion ratchet expires.
            */
            /*
            FNXC:EngineTests 2026-06-26-09:30:
            Quarantined 7 engine-default files failing in CI full-suite run 28259456548 under the deletion ratchet.

            FNXC:EngineTests 2026-06-27-10:05:
            FN-7119 rescued the batch by completing scheduler TaskStore fakes for the engine heartbeat write, fixing override column-agent model preservation, and removing a stale static-guard registry entry for the deleted merger post-merge script path. Keep these files active so loaded shards catch fake drift and model-clobber regressions.
            */
            /*
            FNXC:EngineTests 2026-06-16-19:05:
            FN-6492 verification caught cli-agent-executor as a package-lane-only flake: the hard-cancel assertion failed once and left an ENOTEMPTY temp hook directory, then the file passed in isolation. Quarantine the whole file under the deletion ratchet instead of weakening timing or process assertions.

            FNXC:EngineTests 2026-06-17-16:12:
            FN-6593 deletes cli-agent-executor.test.ts under the ratchet because the package-lane-only hard-cancel/ENOTEMPTY flake did not have a non-appeasement root-cause fix in this follow-up.
            Keep the ledger entry and exclude removed together; git history remains the archive, while executor-recovery.test.ts still covers active CLI task-session hard-cancel cleanup.
            */
            // SQLite-internals quarantine (cutover): see scripts/lib/test-quarantine.json.
            // FNXC:EngineTests 2026-06-25-11:15: SQLite-to-PostgreSQL cutover
            // quarantines engine files exercising SQLite-only behavior (FTS5
            // maintenance scheduling with FUSION_DISABLE_FTS5 + rebuildFts5Index,
            // worktree DB hydration asserting SQLite PRAGMA journal_mode). FTS
            // coverage is replaced by packages/core/src/__tests__/postgres/fts-replacement.test.ts.
            //
            // FNXC:EngineTests 2026-06-25-11:38: Additional engine SQLite-path
            // tests fail under Node 26 node:sqlite ERR_INVALID_ARG_TYPE binding
            // via sqlite-adapter.ts (construct SQLite-backed TaskStore). All
            // pre-existing on clean baseline. Quarantined on sight per AGENTS.md.
            // Pre-existing test/code drift (mock TaskStore missing getAsyncLayer);
            // quarantined on sight per AGENTS.md so verify:workspace goes green.
            /*
            FNXC:EngineTests 2026-06-25-16:30:
            The SQLite-to-PostgreSQL cutover (feature delete-sqlite-runtime-final, PHASE A)
            quarantines the remaining non-quarantined engine test files that construct a
            SQLite-backed store (new TaskStore(..., {inMemoryDb: true}) / new Database(...))
            or use the sync SQLite data path. The SQLite runtime code is being deleted in
            this feature. Per the AGENTS.md flaky-test deletion ratchet, these tests are
            quarantined on sight (not migrated to PG) because they exercise code that will
            be deleted. Mirrored in scripts/lib/test-quarantine.json.
            */
            /*
            FNXC:EngineTests 2026-06-25-18:00:
            The SQLite-to-PostgreSQL cutover (feature delete-sqlite-runtime-final, SESSION 3 PHASE A)
            quarantines remaining engine test files that construct a SQLite-backed store via
            inMemoryDb. These tests exercise the SQLite Database class being deleted in this feature.
            Quarantined on sight per AGENTS.md; mirrored in scripts/lib/test-quarantine.json.
            */
            // SQLite-path gate test evicted + quarantined (see engine-core comment + ledger).
            "node_modules/**",
            "dist/**",
            // FNXC:PgMigrationQuarantine 2026-07-18-04:30: FN-8270 rescued the final seven VAL-REMOVAL-005 holdouts by awaiting PG audit reads and modeling async collaborators. Their paired ledger entries and excludes were removed only after targeted green runs.
            // FNXC:WorkflowStepInstancePersistence 2026-07-16-20:35: FN-8157 restores this PG-backed foreach suite through async store persistence, so it must execute in engine-default.
            /*
            FNXC:EngineTests 2026-07-18-07:30:
            FN-8271 restored heartbeat-error-recovery to engine-default after synchronizing on its first mocked prompt and draining the known retry timers once. This removes the load-amplified thirty-yield fake-timer poll without changing the 30s test timeout or recovery assertions; its matching quarantine-ledger row is removed in lockstep.
            */
            /*
            FNXC:EngineTests 2026-06-14-02:11:
            FN-6433 rescued the AI-merge suites by replacing broad activeSessionRegistry cleanup with path-scoped cleanup, so the default engine lane should execute them again. The soft-delete blocker residue suite was deleted under the ratchet because deterministic soft-delete deadlock coverage already owns that invariant.
            */
          ],
        },
      },
      {
        extends: true,
        test: {
          name: "engine-reliability",
          include: ["src/__tests__/reliability-interactions/**/*.test.ts"],
          // Mirror the engine-default exclusion so reliability slow tests
          // also tier into engine-slow.
          exclude: [
            "src/**/*.slow.test.ts",
            /*
            FNXC:FullSuiteBookkeeping 2026-08-09-03:49:
            dependency-cycle-reconcile and worktrunk-failure from the 2026-08-05 full-suite quarantine wave (run 30982276306) deleted under the deletion ratchet after operator directive. Both tested pre-refactor PG lifecycle-lock and mock-hoist behavior that no longer exists.
            */
            /*
            FNXC:EngineTests 2026-06-26-09:30:
            Quarantined 3 reliability-interactions files failing in CI full-suite run 28259456548 under the deletion ratchet.

            FNXC:EngineTests 2026-06-27-10:05:
            FN-7119 rescued the reliability batch by adding the production `updateSettings` heartbeat surface to scheduler fakes, so lease-recovery and todo/in-progress flapping call-count invariants run under the loaded reliability shard without quarantine.
            */
            /*
            FNXC:EngineTests 2026-06-14-02:12:
            FN-6433 removed the reliability-interactions quarantine after deleting the duplicate soft-delete blocker residue file under the deletion ratchet; keep this project exclude list ledger-free unless a new flake is quarantined in lockstep.

            FNXC:EngineTests 2026-06-25-11:48:
            Pre-existing failure on clean baseline: merge-request-cancel-on-hard-cancel 'cancels pending merge request' asserts expected Promise to be null (timing/ordering). Quarantined on sight per AGENTS.md so verify:workspace goes green; mirrored in scripts/lib/test-quarantine.json.
            */
            // Pre-existing reliability flake (quarantine on sight): see scripts/lib/test-quarantine.json.
            "src/__tests__/reliability-interactions/merge-request-cancel-on-hard-cancel.test.ts",
            /*
            FNXC:EngineTests 2026-06-25-16:30:
            The SQLite-to-PostgreSQL cutover (feature delete-sqlite-runtime-final, PHASE A)
            quarantines the remaining non-quarantined engine reliability-interaction test
            files that construct a SQLite-backed store. The SQLite runtime code is being
            deleted in this feature. Per the AGENTS.md flaky-test deletion ratchet, these
            tests are quarantined on sight (not migrated to PG) because they exercise code
            that will be deleted. Mirrored in scripts/lib/test-quarantine.json.
            */
            // SQLite-path + pre-existing real-git CWD race flake (quarantine on sight).
            /*
            FNXC:EngineTests 2026-06-25-18:00:
            The SQLite-to-PostgreSQL cutover (feature delete-sqlite-runtime-final, SESSION 3 PHASE A)
            quarantines remaining reliability-interaction test files that import _helpers.ts
            (which constructs TaskStore with inMemoryDb:true). These tests exercise the SQLite
            Database class being deleted. Quarantined on sight per AGENTS.md; mirrored in
            scripts/lib/test-quarantine.json.
            */
            // FNXC:PgMigrationQuarantine 2026-07-18-04:30: FN-8270 restored the final VAL-REMOVAL-005 reliability suites with awaited PostgreSQL audit reads. Keep the project partition below while allowing these tests to execute under engine-reliability.
            // FNXC:PgMigrationQuarantine 2026-07-16-04:59:
            // FN-8044 migrated dependency-reconcile suites to the PG corrupt-row seeding seam, so
            // they are deliberately absent from this quarantine list and ledger.
            // FNXC:PgMigrationQuarantine 2026-07-16-10:45:
            // FN-8047 restored multi-node claim and owning-node handoff coverage with shared PG-backed
            // AgentStores and AsyncCentralClaimStore; their paired ledger entries are intentionally live.
            // FNXC:PgMigrationQuarantine 2026-07-16-11:25:
            // FN-8117 restored explicit-marker coverage by configuring its PG fixture with taskPrefix: FN.
            // The strict marker parser now receives valid FN ids, so this file is intentionally unquarantined.
            // FNXC:PgMigrationQuarantine 2026-07-16-11:58:
            // FN-8111 restored meta-archive guard composition with PG-authoritative audits and canonical fixture ids, and fixed completed stale continuations so the in-memory wedge suite is intentionally unquarantined.
            // FNXC:PgMigrationQuarantine 2026-07-16-12:30:
            // FN-8118 verified the already-landed post-done continuation rescue: this pure in-memory suite has no PG fixture and passed its serialized reliability lane three times. Keep it absent from this quarantine list while preserving the engine-default reliability partition exclusion.
          ],
          // These tests assert event ordering across real worktrees. Parallel
          // execution under merger load caused subprocess-guard timeouts and
          // SQLite rowid interleaving (e.g. FN-5521 hit
          // `expected 24 to be less than 19` in merge-reuse-task-worktree).
          // Serialize at the file level; within-file order is already linear.
          minWorkers: 1,
          maxWorkers: 1,
          fileParallelism: false,
        },
      },
      {
        extends: true,
        test: {
          name: "engine-slow",
          // Files matching `*.slow.test.ts` are the long-tail real-git suites
          // (`mkdtemp` + `git init` + multiple commits per test). They run
          // single-threaded to avoid spawning many concurrent git processes
          // and inflating wall time further. Excluded from the default
          // `pnpm test` lane; run via `pnpm test:slow` / `pnpm test:all`.
          include: ["src/**/*.slow.test.ts"],
          /*
          FNXC:EngineTests 2026-06-25-14:30:
          The SQLite-to-PostgreSQL cutover (feature quarantine-sqlite-internals-tests, retry
          session) quarantines 6 engine-slow reliability-interaction test files that fail on
          clean baseline (stash + rerun, 6 failed | 8 passed). These are real-git + SQLite-backed
          branch-group tests that hit the async-satellite getAsyncLayer/isBackendMode mock drift
          or branch-group "undefined not found" errors under the cutover's dual-path. Quarantined
          on sight per AGENTS.md flaky-test rule so verify:workspace goes green. Mirrored in
          scripts/lib/test-quarantine.json.
          */
          exclude: [
            "src/__tests__/merger-ai-dependency-install.slow.test.ts",
            "src/__tests__/reliability-interactions/branch-group-automerge-precedence.slow.test.ts",
            "src/__tests__/reliability-interactions/branch-group-merge-routing.slow.test.ts",
            "src/__tests__/reliability-interactions/branch-group-pr-sync.slow.test.ts",
            "src/__tests__/reliability-interactions/branch-group-single-pr-e2e.slow.test.ts",
            "src/__tests__/reliability-interactions/shared-branch-group-lifecycle.slow.test.ts",
            // SQLite-path (delete-sqlite-runtime-final PHASE A): uses inMemoryDb via _helpers.ts.
          ],
          minWorkers: 1,
          maxWorkers: 1,
          fileParallelism: false,
        },
      },
    ],
    coverage: {
      enabled: false,
      reporter: ["text", "html", "json"],
      reportsDirectory: "./coverage",
      include: ["src/**/*.ts"],
      exclude: ["**/*.test.ts", "**/*.d.ts", "dist/**"],
    },
  },
});