ce-work fixture cache reuses deleted seed repositories across test files #1745

ce-work test files reuse a cached seed repository after another file's cleanup has deleted it. This is reproducible on pristine main at 65dd958da881843868daa219c7f0a5a0e694d9db, before any follow-up edits.

This bug predates and is independent of #1735. The seed cache was introduced in commit 5985d821b9413f590184531d4c35e435d2356abb (2026-08-26, #1548).

Reproduction

Linux x86_64, Bun 1.4.2. In a clean checkout of the commit above:

bun install --frozen-lockfile
bun --version
bun test tests/skills/ce-work-unit-workspace-fallback.test.ts tests/skills/ce-work-unit-workspace-init.test.ts

Result: 17 pass, 17 fail. The failures include:

error: ENOENT: no such file or directory, lstat '/tmp/ce-work-repo-template-.../repo'
  at makeRepo (tests/skills/helpers/ce-work-workspace-harness.ts:127:3)

Each file passes in a separate process:

bun test tests/skills/ce-work-unit-workspace-fallback.test.ts
# 15 pass, 0 fail
bun test tests/skills/ce-work-unit-workspace-init.test.ts
# 19 pass, 0 fail

File isolation also avoids the failure:

bun test --isolate tests/skills/ce-work-unit-workspace-fallback.test.ts tests/skills/ce-work-unit-workspace-init.test.ts
# 34 pass, 0 fail

Root cause and scope

In ce-work-workspace-harness.ts, seedTemplates is a module-level map. seedTemplate() returns its cached path without checking whether the template still exists. The helper's afterAll removes every directory in templateRoots, but does not invalidate the cache. With a shared module registry across files, the next file's makeRepo() calls cpSync() on that deleted path.

This distinction matters for the earlier full-suite report: Bun 1.3.11 does not expose --parallel or --isolate, although the current bun run test script supplies --parallel. On that version, the pristine full suite produced 4099 pass, 2 skip and 62 fail, including 60 missing-template errors. The fallback and init files still passed individually on that version.

With Bun 1.4.2, the repository's normal bun run test uses --parallel, which implies file isolation. Its pristine full run had no missing-template errors (4159 pass, 2 skip, 2 separate route/integration failures). This report is about the deterministic non-isolated multi-file failure, not a claim that current CI's isolated run suffers it.

The existing #1635 report concerns nondeterministic transaction failures within a single integration test file; it does not describe this deleted seed/cache failure.

Related: #1734 and the request for a separate fixture report.