SchedulingPolicy — Specs

Summary

SchedulingPolicy holds the pure timing decisions behind the AX scheduling layer, extracted so they're testable without real clocks or queues (same pattern as SelectionResolver / AxEventRouting):

• ThrottleDecision — for one throttleOrProceed call: run on the leading edge, or (within the window) schedule a single trailing run and coalesce the rest. Used by Throttler and ThrottlerWithKey.
• RetryPolicy — backoff schedule (200ms → 1s → 2s → 5s, then 5s) and the 60s give-up, for retrying an AX call against an unresponsive app. Used by AXCallScheduler.

Test scenarios

Mirrors SchedulingPolicyTests.swift 1:1.

A. ThrottleDecision

• testThrottleFirstCallRunsNow — no prior fire → runNow.
• testThrottleAfterWindowRunsNow — elapsed ≥ delay → runNow (window reset).
• testThrottleWithinWindowSchedulesTail — within window, no tail pending → scheduleTail(remaining).
• testThrottleWithinWindowWithPendingTailCoalesces — within window, tail already pending → coalesce.
• testThrottleClockGoingBackwardsRunsNow — now < last (monotonic-clock guard) → runNow.
• testThrottleBurstCoalescesAfterOneTail — a burst yields one leading run, one scheduleTail, then coalesce for the rest.

B. RetryPolicy

• testRetryBackoffSequence — retry 0/1/2/3/4… → 200ms / 1s / 2s / 5s / 5s.
• testRetryBackoffClampsAndFloors — counts past the last step clamp to 5s; negative counts floor to the first step.
• testRetryGivesUpAtThreshold — elapsed ≥ 60s → give up.
• testRetryDoesNotGiveUpEarly — elapsed < 60s → keep retrying.