* use dyn Trait syntax where appropriate
recent rust nightly started warning that not using `dyn` was
deprecated. This requires MSRV 1.27.0+.
* rustfmt fallout from dyn additions
* stop explicit allow of rust_2018_idioms
* more dyn Trait syntax
* drop tokio-macros from 0.1.x workspace
Since tokio-macros specifies an edition=2018, we would otherwise
require MSRV 1.31.0 to build/test it. And tokio-macros isn't used with
tokio 0.1.x.
* reactor: narrow tokio-io-pool dev dep to 0.1.4
Since 0.1.5-6 is now a edition=2018 crate, which has effective MSRV
1.31.0.
* narrow tempfile dev-dep to avoid MSRV bump
tempfile 3.1.0 pulls in rand 0.7.0 and is MSRV 1.32.0
* narrow flate2 dev-dep to avoid MSRV bump
flate2 1.0.10-11 have MSRV 1.34.0.
github refs: alexcrichton/flate2-rs#207
* fs: drop deprecated tempdir crate use in tests
In particular because it pulls in old rand duplicates. Replace use
with tempfile::tempdir() which has been available since tempfile
3.0.0.
backport-of: #1312
* increase CI MSRV to 1.28.0
When spawning using `Handle` while on the executor, tasks were being
double counted. This prevented the number of active tasks to reach zero,
thus preventing the executor from shutting down.
This changes `spawn` to check if being called from the executor
**before** incrementing the number of active tasks.
Fixes#760
The futures 0.2 crate is not intended for widespread usage. Also, the
futures team is exploring the compat shim route.
If futures 0.3 support is added to Tokio 0.1, then a different
integration route will be explored, making the current code unhelpful.
Extract `tokio::executor::current_thread` to a tokio-current-thread
crate. Deprecated fns stay in the old location. The new crate only
contains thee most recent API.
David Kellum