FA-41815 / Listener lifecycle / Member archive

Observer sequence rollover fails to advance its envelope epoch · case 05

Observer sequence rollover fails to advance its envelope epoch; the returned lifecycle plan violates the stated transition contract.

Member previewVariant 5 · 3 implementations · 8 checks per implementation

Case contract

Copy an observer event envelope according to this finite contract: payload list is copied, headers are copied with private keys removed, origin and correlation are preserved independently, callback index does not replace event sequence, cancellation flags are frame-local, and a redacted event drops only its secret field. Event timestamp zero is valid. These are value-copy semantics, not object identity tests. Origin resolution scans [identity,is_proxy] hops and takes the first nonproxy identity; proxy-only paths have no origin. Correlation scopes are outer-to-inner [explicitly_bound,value]. The innermost explicit binding wins, including None. Increment the epoch/counter sequence and normalize arbitrary recovered counter overflow using the positive modulus. Public invocation positions are zero-based among enabled [callback_id,enabled] slots, not physical registry indices. Read cancellation by exact current frame identity; missing frame flags default false. Inputs are finite state snapshots, including transitional and stale states; output fields are the exact independent actions/metadata defined by the corrected expression table. Numeric fixture capacities and counts vary with N. Field definitions, each independently computed from the input snapshot: payload = list(s['payload']); headers = {k:v for k,v in s['headers'].items() if not k.startswith('_')}; origin = next((r[0] for r in s['hops'] if not r[1]),None); correlation = next((r[1] for r in reversed(s['correlation_scopes']) if r[0]),None); sequence = [s['epoch']+(s['counter']+1)//s['modulus'],(s['counter']+1)%s['modulus']]; index = [[r[0],i] for i,r in enumerate(r for r in s['slots'] if r[1])]; timestamp = s['timestamp']; secret = None if s['redact'] else s['secret']; cancelled = s['frame_flags'].get(s['frame'],False); public_count = sum(not k.startswith('_') for k in s['headers'])

Why this case matters

Observer implementations need to preserve this state while subscriptions enter, execute, and leave their lifecycle.

One recorded failure

Sample boundary fixture

This sample comes from the broken implementation of a controlled reproducer.

Boundary fixture	Actual	Expected	Outcome
transition 0	`{"cancelled": false, "correlation": null, "headers": {"mid_key": "z", "public": "x"}, "index": [["a", 0], ["c", 1]], "origin": "source", "payload": [0, 1, 10], "public_count": 2, "secret": null, "sequence": [0, 0], "timestamp": 0}`	`{"cancelled": false, "correlation": null, "headers": {"mid_key": "z", "public": "x"}, "index": [["a", 0], ["c", 1]], "origin": "source", "payload": [0, 1, 10], "public_count": 2, "secret": null, "sequence": [11, 0], "timestamp": 0}`	Failed

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