feat: Rework the internal structure of the event-listener crate

.github/workflows/ci.yml

@@ -37,8 +37,9 @@ jobs:
       - name: Run cargo check (without dev-dependencies to catch missing feature flags)
         if: startsWith(matrix.rust, 'nightly')
         run: cargo check -Z features=dev_dep
-      - run: cargo test --features __test --all
-      - run: cargo build --no-default-features --all
+      - run: cargo test --all
+      - run: cargo test --no-default-features --tests
+      - run: cargo build -p event-listener-strategy --no-default-features
       - name: Install cargo-hack
         uses: taiki-e/install-action@cargo-hack
       - run: rustup target add thumbv7m-none-eabi
@@ -56,6 +57,7 @@ jobs:
       - name: Install Rust
         run: rustup update ${{ matrix.rust }} && rustup default ${{ matrix.rust }}
       - run: cargo build --all
+      - run: cargo build --all --no-default-features
 
   clippy:
     runs-on: ubuntu-latest
@@ -79,7 +81,7 @@ jobs:
       - uses: actions/checkout@v3
       - name: Install Rust
         run: rustup toolchain install nightly --component miri && rustup default nightly
-      - run: cargo miri test --features __test --all
+      - run: cargo miri test --all
         env:
           MIRIFLAGS: -Zmiri-strict-provenance -Zmiri-symbolic-alignment-check -Zmiri-disable-isolation
           RUSTFLAGS: ${{ env.RUSTFLAGS }} -Z randomize-layout

Cargo.toml

@@ -18,15 +18,11 @@ exclude = ["/.*"]
 default = ["std"]
 std = ["parking"]
 
-# Unstable, test only feature. Do not enable this.
-__test = []
-
 [dependencies]
-crossbeam-utils = { version = "0.8.12", default-features = false }
 parking = { version = "2.0.0", optional = true }
-slab = { version = "0.4.7", default-features = false }
 
 [dev-dependencies]
+futures-lite = "1.12.0"
 waker-fn = "1"
 
 [dev-dependencies.criterion]

benches/bench.rs

@@ -1,22 +1,31 @@
+use std::iter;
+use std::pin::Pin;
+
 use criterion::{criterion_group, criterion_main, Criterion};
-use event_listener::Event;
+use event_listener::{Event, EventListener};
 
 const COUNT: usize = 8000;
 
 fn bench_events(c: &mut Criterion) {
     c.bench_function("notify_and_wait", |b| {
         let ev = Event::new();
-        b.iter(|| {
-            let mut handles = Vec::with_capacity(COUNT);
+        let mut handles = iter::repeat_with(|| EventListener::new(&ev))
+            .take(COUNT)
+            .collect::<Vec<_>>();
 
-            for _ in 0..COUNT {
-                handles.push(ev.listen());
+        b.iter(|| {
+            for handle in &mut handles {
+                // SAFETY: The handle is not moved out.
+                let listener = unsafe { Pin::new_unchecked(handle) };
+                listener.listen();
             }
 
             ev.notify(COUNT);
 
-            for handle in handles {
-                handle.wait();
+            for handle in &mut handles {
+                // SAFETY: The handle is not moved out.
+                let listener = unsafe { Pin::new_unchecked(handle) };
+                listener.wait();
             }
         });
     });

examples/mutex.rs

@@ -63,9 +63,9 @@ impl<T> Mutex<T> {
                     // Start listening and then try locking again.
                     listener = Some(self.lock_ops.listen());
                 }
-                Some(l) => {
+                Some(mut l) => {
                     // Wait until a notification is received.
-                    l.wait();
+                    l.as_mut().wait();
                 }
             }
         }
@@ -88,9 +88,9 @@ impl<T> Mutex<T> {
                     // Start listening and then try locking again.
                     listener = Some(self.lock_ops.listen());
                 }
-                Some(l) => {
+                Some(mut l) => {
                     // Wait until a notification is received.
-                    if !l.wait_deadline(deadline) {
+                    if !l.as_mut().wait_deadline(deadline) {
                         return None;
                     }
                 }