Dedicated exceptions for `read` failures reduce the risk of mixing up
"user" exceptions with those of Future itself. The risk still exists, if
the user allows a chronos exception to bubble up explicitly.
Because `await` structurally guarantees that the Future is not `pending`
at the time of `read`, it does not raise this new exception.
* introduce `FuturePendingError` and `FutureCompletedError` when
`read`:ing a future of uncertain state
* fix `waitFor` / `read` to return `lent` values
* simplify code generation for `void`-returning async procs
* document `Raising` type helper
* Add callTick and stream cancellation tests.
* Fix stepsAsync() test.
* Cancellation changes.
* Update and add more cancellation tests.
* Fix Posix shutdown call to handle ENOTCONN error.
* With new changes to to cancellation its now possible.
* Refactor testsoon.nim to not produce artifacts after tests are finished.
* Debugging MacOS issue.
* Adjust flaky test times.
* Fix issue.
* Add test for issue #334 which was also addressed in this PR.
Avoid `break` in problematic test.
* Add noCancelWait() call which prohibits cancellation.
Fix closeWait() calls to use noCancelWait() predicate.
Adding sleep to flaky MacOS test.
* Remove all debugging echoes.
* Fix cancelAndWait() which now could perform multiple attempts to cancel target Future (mustCancel behavior).
* Fix issues revealed by switch to different cancelAndWait().
* Address review comments.
* Fix testutils compilation warning.
* Rename callTick() to internalCallTick().
* Add some documentation comments.
* Disable flaky ratelimit test.
* Rename noCancelWait() to noCancel().
Address review comments.
* move `Future[T]` into its own module along with some basic accessors
* mark all fields internal, exposing only read-only versions under the
old names
* introduce `init`/`completed`/etc as a way of creating a future (vs
newFuture)
* introduce `LocationKind` for `SrcLoc` access
* don't expose `FutureList` unless future tracking is enabled
* introduce `chronosStrictFutureAccess` which controls a number of
additional `Defect` being raised when accessing Future fields in the
wrong state - this will become true in a future version
In this version, `Future[T]` backwards compatibility code remains in
`asyncfutures2` meaning that if only `chronos/futures` is imported, only
"new" API is available.
This branch is a refinement / less invasive / minimal version of
https://github.com/status-im/nim-chronos/pull/373.