Fix promise sync in bool_waiter; rename to callback_waiter #48
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Rebased on top of #47. |
We were setting the promise in bool_waiter *before* we call the wrapped lambda, but that introduces a race condition because we have test code that waits on the promise and then checks a value that it expects to have been set inside the lambda. This reverses it so that the promise is set *after* the lambda is called, which should solve the intermittent failure of the 009 test caused by exactly this race condition. While here, I also refactored this to a `promise<void>` since we are never actually meaningfully using the `bool` value (which either returns true, or hangs), and then since it isn't a "bool" waiter anymore, renamed to callback_waiter. `get` doesn't seem useful (it basically is a return-or-hang), so I removed it. `wait_ready()` felt too long, so I shortened it to `wait()`. Also adds documentation of the usage of `bool_waiter`.
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We were setting the promise in bool_waiter before we call the wrapped lambda, but that introduces a race condition because we have test code that waits on the promise and then checks a value that it expects to have been set inside the lambda.
This reverses it so that the promise is set after the lambda is called.
While here, I also refactored this to a
promise<void>since we are never actually meaningfully using theboolvalue (it is only ever set totrue) and removed theget()function (since the only difference between it andwait_ready()is thatget()can hang forever), and then since it isn't a "bool" waiter anymore, renamed the whole thing to callback_waiter.Edit: also renamed
wait_readytowaitAlso documented its usage.