wait_for_peers reads the connected-peer count through a pipeline ending in
`|| echo 0`, so a container that never answers contributes 0. That is safe
against a floor of 1 or more, where 0 reads as "not converged yet" and the wait
eventually times out, and it is unsafe against a floor of 0, where the first
read from a dead container satisfies the wait and the caller proceeds as though
convergence had been observed.
No caller passes 0 today; every one passes 1 or more, and the single variable
minimum is advisory. Rather than harden the reader, reject the input: a floor
below 1 is now an error. That makes the shape unreachable instead of repairing
instances of it, and it costs a future caller nothing except a clear message
saying that asserting "exactly zero peers" needs a reader that distinguishes no
answer from zero, which this floor is not.
wait_for_links goes with it. It had no caller anywhere in the tree on any
branch, and it carried the identical fallback, so the only thing it could do was
hand the hazard to whoever called it first. An uncalled helper cannot be wrong
today, which is exactly why it was the risk worth removing rather than the one
worth keeping for symmetry.
The hermetic gate suite gains a case covering both directions, with docker
stubbed so it stays container-free: a floor of 0 is refused with a message
naming why, and the same unreachable container with a floor of 1 still polls its
full budget and times out. Verified by removing the guard and confirming exactly
the three zero-floor assertions red while both floor-of-one controls stay green.
wait_until_connected fail-fasted on stall even when the mesh was all but
converged, abandoning the run with budget still unspent because one hard
pair straggled to come up. On the rekey-outbound-only topology this turned a
rare deep-node timing straggle (stacked discovery backoff + late bloom
propagation, which clears well inside the budget) into a false baseline RED.
Add a near_converged_slack threshold (default 2): when the number of
still-failing pairs is at or below the slack and the stall window elapses,
keep polling toward max_secs instead of bailing. A mesh genuinely far from
convergence still fast-bails on stall, and a never-converging pair still
hits the hard cap, so a real regression is never masked.
Add a self-contained behavioral test (wait-converge-test.sh) covering the
four contract cases: near-converged hold (with a slack=0 contrast that
proves the slack is what saves the run), far-from-converged fast-bail,
never-converging hard cap, and four-argument backward compatibility.
Add wait_until_connected to the shared convergence helpers: it polls a
suite's own pairwise pings (the signal it actually asserts on), returns
as soon as every pair is reachable, extends its deadline while the
reachable-pair count is still climbing, and gives up only when progress
stalls.
Use it in the rekey, static-mesh, and sidecar suites in place of the
fixed wall-clock baseline timeout and the blind sleep, which timed out
under concurrent CI load while the mesh was still converging.
Johnathan Corgan