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Exhaust counts every outer value as dropped, including accepted values · case 04

Exhaust counts every outer value as dropped, including accepted values; the returned lifecycle plan violates the stated transition contract.

Member previewVariant 4 · 3 implementations · 8 checks per implementation

Case contract

Plan an exhaust-style observer: accept a new outer value only while no inner is active; otherwise drop it, never queue or replace. An accepted inner occupies its slot before synchronous subscription side effects. Releasing the current inner allows the next outer value. Outer completion waits for the accepted inner. An error is terminal and rejected outer values consume no inner generation. For one accepted inner, report the earliest trace index at which both outer and inner completion have occurred, independent of later trace records. Suppressed outer values are never queued; their [resource_id,owned] resources are released only when owned by the operator. For recorded [outer_value,inner_active_at_arrival] observations, invoke the inner factory only for arrivals that found the slot idle. For one inner startup, reservation is occupied from reserve until complete, even if completion is synchronous before subscribe returns; return alone does not release it. 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: accept = s['outer_value'] and not s['active'] and not s['subscribing'] and not s['outer_done'] and not s['cancel'] and s['error'] is None; drop = s['outer_value'] and (s['active'] or s['subscribing']); queue = [r[0] for r in s['discarded_resources'] if r[1]]; replace = [r[0] for r in s['outer_arrivals'] if not r[1]]; reserved = [sum(op=='reserve' for op in s['reservation_trace'][:i+1])>sum(op=='complete' for op in s['reservation_trace'][:i+1]) for i in range(len(s['reservation_trace']))]; release = s['inner_done'] and s['done_generation']==s['generation']; finish = max(s['finish_trace'].index('outer-done'),s['finish_trace'].index('inner-done')) if 'outer-done' in s['finish_trace'] and 'inner-done' in s['finish_trace'] else None; generation = s['generation']+int(s['outer_value'] and not s['active'] and not s['subscribing']); drops = s['drops']+int(s['outer_value'] and (s['active'] or s['subscribing'])); detach_inner = (s['active'] or s['subscribing']) and (s['cancel'] or s['error'] is not None)

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 1	`{"accept": false, "detach_inner": false, "drop": true, "drops": 12, "finish": null, "generation": 9, "queue": [], "release": false, "replace": [], "reserved": []}`	`{"accept": false, "detach_inner": false, "drop": false, "drops": 12, "finish": null, "generation": 9, "queue": [], "release": false, "replace": [], "reserved": []}`	Failed

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