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qmuntal / stateless

Go library for creating finite state machines
BSD 2-Clause "Simplified" License
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fix potential issue of statemachine trigger lost #69

Closed liang-kang closed 10 months ago

liang-kang commented 10 months ago

there exists a tiny gap between finishing iterations of firing queued event and sm.op decrease

If another routine run internalFireQueued in that gap, it will not firing but save trigger in eventqueue and return.

Meanwhile, origin routine will not check event queue again because interations has finished

so such trigger event will be left in queue and wait for later firing trigger to executing. If no trigger again, this trigger event will wait for ever and break run-to-complete

BTW, it's better not to execute all event in one loop, which may cause Fire() caller waits for a long time to execute some actions not belong to current trigger. So, in each loop, try to compare and swap sm.ops from 0 to 1, if failed, let current routine has chance to return.

qmuntal commented 10 months ago

Thanks @liang-kang. I like the proposed changes. Merging.