The unit + integration tests can't cross machine.Start — the SDK
boundary would need a fake firecracker that reimplements the
control-plane HTTP API, and the ongoing maintenance cost of keeping
that fake honest with upstream kills the value. Instead, add a
pre-release smoke target that drives REAL Firecracker + real KVM,
captures coverage from the -cover-instrumented binaries, and
surfaces per-package deltas so regressions in the boot path don't
ship silently.
scripts/smoke.sh:
- Isolated XDG_{CONFIG,STATE,CACHE,RUNTIME} so the smoke run can't
touch real user state (state/cache persist under build/smoke/xdg
for fast reruns; runtime is mktemp'd fresh per-run because
sockets can't be reused)
- Preflight: `banger doctor` must pass; UDP :42069 must be free
(otherwise the user's real daemon is up and the smoke daemon
can't bind its DNS listener — fail with an actionable message)
- Scenario 1 — bare: `banger vm run --rm -- echo smoke-bare-ok`
exercises create → start → socket ownership chown → machine.Start
→ SDK waitForSocket race → vsock agent readiness → guest SSH
wait → exec → cleanup → delete
- Scenario 2 — workspace: creates a throwaway git repo, runs
`banger vm run --rm <repo> -- cat /root/repo/smoke-file.txt`,
verifies the tracked file reached the guest (exercises
workDisk capability PrepareHost + workspace.prepare)
- `banger daemon stop` at the end so instrumented binaries flush
GOCOVERDIR pods before the script exits
Makefile additions:
- smoke-build: builds banger/bangerd under build/smoke/bin/ with
`go build -cover`
- smoke: runs the script with GOCOVERDIR set, reports per-package
coverage via `go tool covdata percent`
- smoke-coverage-html: textfmt + go tool cover for a browsable
report
- smoke-clean: nukes build/smoke/ including the persisted XDG
state
Bonus fix uncovered during the first smoke run: doctor treated a
missing state.db as a FAIL ("out of memory" from SQLite
SQLITE_CANTOPEN), which red-flagged every fresh install. Split
the store check: DB file absent → PASS with "will be created on
first daemon start" detail; DB present but unreadable → FAIL as
before. New TestDoctorReport_StoreMissingSurfacesAsPassForFreshInstall
pins the behaviour.
Concrete coverage delta from the first successful smoke run
(compared to `make coverage-total`'s unit-test-only 37.8%):
internal/firecracker 43.6% → 75.0%
internal/daemon/workspace 33.8% → 60.8%
internal/store 40.1% → 56.3%
internal/guest 63.7% → 57.4% (different mix: smoke
exercises real SSH;
unit tests cover more
error branches)
The packages the review flagged are the ones that moved most —
which is the point.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Three thematic test files pinning behavior surfaces that had none
before, following the review's recommendation to plug concrete
error/cleanup branches rather than chase a coverage percentage.
doctor_test.go
Covers Daemon.doctorReport end-to-end with a permissive runner +
fake executables on PATH. Pins: store error surfaces as fail,
store success as pass, missing firecracker kills the host-runtime
check, the three default capability feature checks (work disk,
vm dns, nat) are emitted, vm-defaults is always-pass with
provenance. Previously 0% — now the Doctor() command's contract
with the CLI is under guard.
workspace_rejection_test.go
Covers the four early-exit branches of PrepareVMWorkspace that
the existing happy-path + lock-release tests never hit: malformed
mode, --from without --branch, VM not running, VM not found.
Each one returns before any SSH I/O, so the fake-firecracker
infra the happy-path test needs is unnecessary — a bare wired
daemon with a stored VMRecord suffices.
nat_capability_test.go
Covers natCapability.ApplyConfigChange (unchanged flag → no-op,
VM not alive → no-op, toggle on live VM → runner reached) and
natCapability.Cleanup (NAT disabled → no-op, runtime handles
missing → defensive no-op, full wiring → ensureNAT(false)). A
countingRunner + startFakeFirecracker fixture stands in for the
real host plumbing, with waitForVMAlive polling past the
exec -a race window that startFakeFirecracker exposes on
loaded CI boxes.
make coverage-total 37.8% → 38.6%. The number isn't the point —
these tests exist so the next refactor in this area has to
break an explicit assertion to drift.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
