Struct BackgroundExecutor 

pub struct BackgroundExecutor { /* private fields */ }

A pointer to the executor that is currently running, for spawning background tasks.

Implementations

impl BackgroundExecutor

BackgroundExecutor lets you run things on background threads. In production this is a thread pool with no ordering guarantees. In tests this is simulated by running tasks one by one in a deterministic (but arbitrary) order controlled by the SEED environment variable.

pub fn spawn<R>( &self, future: impl Future<Output = R> + Send + 'static, ) -> Task<R>

where R: Send + 'static,

Enqueues the given future to be run to completion on a background thread.

pub fn spawn_labeled<R>( &self, label: TaskLabel, future: impl Future<Output = R> + Send + 'static, ) -> Task<R>

where R: Send + 'static,

Enqueues the given future to be run to completion on a background thread. The given label can be used to control the priority of the task in tests.

pub fn block<R>(&self, future: impl Future<Output = R>) -> R

Block the current thread until the given future resolves. Consider using block_with_timeout instead.

pub fn block_with_timeout<Fut: Future>( &self, duration: Duration, future: Fut, ) -> Result<Fut::Output, impl Future<Output = Fut::Output> + use<Fut>>

Block the current thread until the given future resolves or duration has elapsed.

pub async fn scoped<'scope, F>(&self, scheduler: F)

where F: FnOnce(&mut Scope<'scope>),

Scoped lets you start a number of tasks and waits for all of them to complete before returning.

pub fn now(&self) -> Instant

Get the current time.

Calling this instead of std::time::Instant::now allows the use of fake timers in tests.

pub fn timer(&self, duration: Duration) -> Task<()>

Returns a task that will complete after the given duration. Depending on other concurrent tasks the elapsed duration may be longer than requested.

pub fn num_cpus(&self) -> usize

How many CPUs are available to the dispatcher.

pub fn is_main_thread(&self) -> bool

Whether we’re on the main thread.

Trait Implementations

impl Clone for BackgroundExecutor

fn clone(&self) -> BackgroundExecutor

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.