testing/connection_closer_helpers.ts

Pin {method, id} on a single recorded close call without baking in the at: N sequence number. Use at every "did the closer fire?" assertion site; the sequence number is only meaningful for dedicated ordering tests (paired with create_emit_ordering_audit_factory).

Throws via assert.ok if call is undefined — index a recorded calls array directly (calls[0]) and let this helper handle the missing-element case.

Build a ConnectionCloser that records every call into calls rather than touching real transports. Each method returns 1 ("one socket closed") regardless of whether a real socket exists — handlers typically ignore the return value.

Pass seq_ref to share the sequence counter with a sibling create_emit_ordering_audit_factory so tests can pin close-vs-emit ordering at the handler call site. Without seq_ref, the closer uses a fresh internal counter — at: N values within a single test are meaningful, but cannot be compared against audit emit ordering.

Record of a single ConnectionCloser method invocation. at is the value of a monotonically-increasing sequence counter at the time of the call — pair with create_emit_ordering_audit_factory to record both close + audit emit calls into the same sequence for ordering tests.