Simply exposes the number of available permits of the semaphore.
This makes some kinds of bookkeeping easier without having to manually keep counts using atomics.
Fixes#2642
Fixes#2388
Previously `#[tokio::test]` would error on functions that took
arguments. That meant other attribute macros couldn't do further
transformations on them. This changes that so arguments are forwarded as
is.
Whatever else might be included on the function is forwarded as well.
For example return type, generics, etc.
Worth noting that this is only for compatibility with other macros.
`#[test]`s that take arguments will still fail to compile.
A bit odd that [trybuild] tests don't fail `#[test]` functions with
arguments which is why the new tests are run with `t.pass(...)`. They do
actually fail if part of a real crate.
[trybuild]: https://crates.io/crates/trybuild
When aborting a task registered with a current-thread scheduler from off runtime, the tasks may not
be immediately unlinked from the runtime. Instead, send a message to the runtime, notifying it to
remove the aborted task.
Fixes#3662
## Motivation
The `tokio::sync::Semaphore` type provides a
[`Semaphore::available_permits` method][1] which returns the current
number of permits available on the semaphore.
`tokio_util::sync::PollSemaphore` [does not expose such a method][2]. It
is possible to use `PollSemaphore::into_inner` or
`PollSemaphore::clone_inner` to unwrap the inner semaphore, but this may
require cloning/dropping the semaphore's `Arc` which shouldn't be
necessary to access the permits.
## Solution
This commit adds `PollSemaphore::available_permits`. It also adds
`PollSemaphore::add_permits` and an `AsRef<Semaphore>` impl while
we're here.
[1]: https://docs.rs/tokio/1.4.0/tokio/sync/struct.Semaphore.html#method.available_permits
[2]: https://docs.rs/tokio-util/0.6.5/tokio_util/sync/struct.PollSemaphore.html#implementationsCloses#3682
Improves a few of the error messages for `#[tokio::main]` and `#[tokio::test]`.
Also adds a note to the docs about `start_paused` requiring the `test-util` feature which wasn't mentioned previously.
Add `runtime::Handle::block_on`. The function enters the runtime context and
blocks the current thread while the future executes.
Refs: #3097Fixes#2965, #3096
I ran into this when writing the docs for `Handle::block_on`. Seems to
be caused by a bug in cargo. Until that is fixed I think it makes sense
to mention it in the contributing guide.
William Manley