* exception tracking
This PR adds minimal exception tracking to chronos, moving the goalpost
one step further.
In particular, it becomes invalid to raise exceptions from `callSoon`
callbacks: this is critical for writing correct error handling because
there's no reasonable way that a user of chronos can possibly _reason_
about exceptions coming out of there: the event loop will be in an
indeterminite state when the loop is executing an _random_ callback.
As expected, there are several issues in the error handling of chronos:
in particular, it will end up in an inconsistent internal state whenever
the selector loop operations fail, because the internal state update
functions are not written in an exception-safe way. This PR turns this
into a Defect, which probably is not the optimal way of handling things
- expect more work to be done here.
Some API have no way of reporting back errors to callers - for example,
when something fails in the accept loop, there's not much it can do, and
no way to report it back to the user of the API - this has been fixed
with the new accept flow - the old one should be deprecated.
Finally, there is information loss in the API: in composite operations
like `poll` and `waitFor` there's no way to differentiate internal
errors from user-level errors originating from callbacks.
* store `CatchableError` in future
* annotate proc's with correct raises information
* `selectors2` to avoid non-CatchableError IOSelectorsException
* `$` should never raise
* remove unnecessary gcsafe annotations
* fix exceptions leaking out of timer waits
* fix some imports
* functions must signal raising the union of all exceptions across all
platforms to enable cross-platform code
* switch to unittest2
* add `selectors2` which supercedes the std library version and fixes
several exception handling issues in there
* fixes
* docs, platform-independent eh specifiers for some functions
* add feature flag for strict exception mode
also bump version to 3.0.0 - _most_ existing code should be compatible
with this version of exception handling but some things might need
fixing - callbacks, existing raises specifications etc.
* fix AsyncCheck for non-void T
* Fix `locked` flag to be more consistent.
Refactor AsyncLock to not use `result`.
Add test for `locked` flag.
* Fixes.
* Fix imports.
* Fix multiple release() without scheduler.
Add more tests.
* Fix review comments.
* small fixes
* more efficient codegen for nil check (much less code)
* release futures earlier in AsyncEvent
* release finished future earlier in AsyncQueue
* avoid searches for futures (deque variant unused / broken)
* avoid catching defects
* Fix AsyncEvent test, because of optimization.
* delete fix
* avoid seq allocs
* Keep style consistent with other code.
Refactor AsyncEvent and AsyncQueue to not use `result` keyword.
Co-authored-by: cheatfate <eugene.kabanov@status.im>
Jacek Sieka
Eugene Kabanov
Araq
Mamy Ratsimbazafy
cheatfate