Trait SinkTestExt

pub trait SinkTestExt<Item>: Sink<Item> {
    // Provided methods
    fn assert_unmoved_sink(self) -> AssertUnmoved<Self> 
       where Self: Sized { ... }
    fn interleave_pending_sink(self) -> InterleavePending<Self> 
       where Self: Sized { ... }
    fn track_closed(self) -> TrackClosed<Self>
       where Self: Sized { ... }
}

Additional combinators for testing sinks.

Provided Methods

fn assert_unmoved_sink(self) -> AssertUnmoved<Self>

where Self: Sized,

Asserts that the given is not moved after being polled.

A check for movement is performed each time the sink is polled and when Drop is called.

Aside from keeping track of the location at which the sink was first polled and providing assertions, this sink adds no runtime behavior and simply delegates to the child sink.

fn interleave_pending_sink(self) -> InterleavePending<Self>

where Self: Sized,

Introduces an extra Poll::Pending in between each operation on the sink.

fn track_closed(self) -> TrackClosed<Self>

where Self: Sized,

Track whether this sink has been closed and panics if it is used after closing.

Examples

use futures::sink::{SinkExt, drain};
use futures_test::sink::SinkTestExt;

let mut sink = drain::<i32>().track_closed();

sink.send(1).await?;
assert!(!sink.is_closed());
sink.close().await?;
assert!(sink.is_closed());

Note: Unlike AsyncWriteTestExt::track_closed when used as a sink the adaptor will panic if closed too early as there’s no easy way to integrate as an error.

use std::panic::AssertUnwindSafe;
use futures::{sink::{SinkExt, drain}, future::FutureExt};
use futures_test::sink::SinkTestExt;

let mut sink = drain::<i32>().track_closed();

sink.close().await?;
assert!(AssertUnwindSafe(sink.send(1)).catch_unwind().await.is_err());

Implementors

impl<Item, W> SinkTestExt<Item> for W

where W: Sink<Item>,