feat: smol runtime

.github/workflows/ci.yml

@@ -28,7 +28,7 @@ jobs:
     runs-on: ${{ matrix.os }}
     strategy:
       matrix:
-        rust: [1.70.0, stable]
+        rust: [1.81.0, stable]
         os: [ubuntu-latest, macOS-latest, windows-latest]
 
     steps:
@@ -50,3 +50,7 @@ jobs:
         run: cargo check --no-default-features --features tokio-runtime,link_to
       - name: Run unit tests (Tokio)
         run: cargo test --verbose --no-default-features --features tokio-runtime,link_to --lib
+      - name: Check (Smol)
+        run: cargo check --no-default-features --features smol-runtime,link_to
+      - name: Run unit tests (Smol)
+        run: cargo test --verbose --no-default-features --features smol-runtime,link_to --lib

Cargo.toml

@@ -17,6 +17,7 @@ either = "1.6.1"
 futures = { version = "0.3.17", optional = true }
 hex = "0.4.3"
 memmap2 = { version = "0.5.8", optional = true }
+smol = { version = "2.0.0", optional = true }
 miette = "5.7.0"
 reflink-copy = "0.1.9"
 serde = "1.0.130"
@@ -43,6 +44,8 @@ libc = { version = "0.2.144", optional = true }
 async-attributes = { version = "1.1.2" }
 criterion = "0.4.0"
 lazy_static = "1.4.0"
+smol-macros = "0.1.1"
+macro_rules_attribute = "0.2.0"
 tokio = { version = "1.12.0", features = [
     "fs",
     "io-util",
@@ -61,3 +64,4 @@ mmap = ["memmap2", "libc"]
 async-std = ["dep:async-std", "futures"]
 link_to = []
 tokio-runtime = ["tokio", "tokio-stream", "futures"]
+smol-runtime = ["smol", "futures"]

benches/benchmarks.rs

@@ -1,5 +1,7 @@
 #[cfg(feature = "async-std")]
 use async_std::fs as afs;
+#[cfg(feature = "smol")]
+use smol::fs as afs;
 #[cfg(feature = "link_to")]
 use std::path::PathBuf;
 #[cfg(all(test, feature = "tokio"))]
@@ -22,6 +24,15 @@ where
     TOKIO_RUNTIME.block_on(future)
 }
 
+#[cfg(all(test, feature = "smol"))]
+#[inline]
+pub fn block_on<F, T>(future: F) -> T
+where
+    F: std::future::Future<Output = T>,
+{
+    smol::block_on(future)
+}
+
 use std::fs::{self, File};
 use std::io::prelude::*;
 
@@ -62,7 +73,7 @@ fn baseline_read_many_sync(c: &mut Criterion) {
     });
 }
 
-#[cfg(any(feature = "async-std", feature = "tokio"))]
+#[cfg(any(feature = "async-std", feature = "tokio", feature = "smol"))]
 fn baseline_read_async(c: &mut Criterion) {
     let tmp = tempfile::tempdir().unwrap();
     let path = tmp.path().join("test_file");
@@ -75,7 +86,7 @@ fn baseline_read_async(c: &mut Criterion) {
     });
 }
 
-#[cfg(any(feature = "async-std", feature = "tokio"))]
+#[cfg(any(feature = "async-std", feature = "tokio", feature = "smol"))]
 fn baseline_read_many_async(c: &mut Criterion) {
     let tmp = tempfile::tempdir().unwrap();
     let paths: Vec<_> = (0..)
@@ -190,7 +201,7 @@ fn read_hash_sync_big_data_xxh3(c: &mut Criterion) {
     });
 }
 
-#[cfg(any(feature = "async-std", feature = "tokio"))]
+#[cfg(any(feature = "async-std", feature = "tokio", feature = "smol"))]
 fn read_hash_many_async(c: &mut Criterion) {
     let tmp = tempfile::tempdir().unwrap();
     let cache = tmp.path().to_owned();
@@ -212,7 +223,7 @@ fn read_hash_many_async(c: &mut Criterion) {
     });
 }
 
-#[cfg(any(feature = "async-std", feature = "tokio"))]
+#[cfg(any(feature = "async-std", feature = "tokio", feature = "smol"))]
 fn read_hash_async(c: &mut Criterion) {
     let tmp = tempfile::tempdir().unwrap();
     let cache = tmp.path().to_owned();
@@ -223,7 +234,7 @@ fn read_hash_async(c: &mut Criterion) {
     });
 }
 
-#[cfg(any(feature = "async-std", feature = "tokio"))]
+#[cfg(any(feature = "async-std", feature = "tokio", feature = "smol"))]
 fn read_async(c: &mut Criterion) {
     let tmp = tempfile::tempdir().unwrap();
     let cache = tmp.path().to_owned();
@@ -234,7 +245,7 @@ fn read_async(c: &mut Criterion) {
     });
 }
 
-#[cfg(any(feature = "async-std", feature = "tokio"))]
+#[cfg(any(feature = "async-std", feature = "tokio", feature = "smol"))]
 fn read_hash_async_big_data(c: &mut Criterion) {
     let tmp = tempfile::tempdir().unwrap();
     let cache = tmp.path().to_owned();
@@ -278,7 +289,7 @@ fn write_hash_xxh3(c: &mut Criterion) {
     });
 }
 
-#[cfg(any(feature = "async-std", feature = "tokio"))]
+#[cfg(any(feature = "async-std", feature = "tokio", feature = "smol"))]
 fn write_hash_async(c: &mut Criterion) {
     let tmp = tempfile::tempdir().unwrap();
     let cache = tmp.path().to_owned();
@@ -293,7 +304,7 @@ fn write_hash_async(c: &mut Criterion) {
     });
 }
 
-#[cfg(any(feature = "async-std", feature = "tokio"))]
+#[cfg(any(feature = "async-std", feature = "tokio", feature = "smol"))]
 fn write_hash_async_xxh3(c: &mut Criterion) {
     let tmp = tempfile::tempdir().unwrap();
     let cache = tmp.path().to_owned();
@@ -325,7 +336,7 @@ fn create_tmpfile(tmp: &tempfile::TempDir, buf: &[u8]) -> PathBuf {
 }
 
 #[cfg(feature = "link_to")]
-#[cfg(any(feature = "async-std", feature = "tokio"))]
+#[cfg(any(feature = "async-std", feature = "tokio", feature = "smol"))]
 fn link_to_async(c: &mut Criterion) {
     let tmp = tempfile::tempdir().unwrap();
     let target = create_tmpfile(&tmp, b"hello world");
@@ -348,7 +359,10 @@ fn link_to_async(c: &mut Criterion) {
     });
 }
 
-#[cfg(all(feature = "link_to", any(feature = "async-std", feature = "tokio")))]
+#[cfg(all(
+    feature = "link_to",
+    any(feature = "async-std", feature = "tokio", feature = "smol")
+))]
 fn link_to_hash_async(c: &mut Criterion) {
     let tmp = tempfile::tempdir().unwrap();
     let target = create_tmpfile(&tmp, b"hello world");
@@ -405,7 +419,7 @@ criterion_group!(
     read_hash_sync_big_data_xxh3,
 );
 
-#[cfg(any(feature = "async-std", feature = "tokio"))]
+#[cfg(any(feature = "async-std", feature = "tokio", feature = "smol"))]
 criterion_group!(
     benches_async,
     baseline_read_async,
@@ -418,23 +432,29 @@ criterion_group!(
     read_hash_async_big_data,
 );
 
-#[cfg(all(feature = "link_to", any(feature = "async-std", feature = "tokio")))]
+#[cfg(all(
+    feature = "link_to",
+    any(feature = "async-std", feature = "tokio", feature = "smol")
+))]
 criterion_group!(link_to_benches_async, link_to_async, link_to_hash_async,);
 
 #[cfg(feature = "link_to")]
 criterion_group!(link_to_benches, link_to_sync, link_to_hash_sync);
 
 #[cfg(all(
     feature = "link_to",
-    not(any(feature = "async-std", feature = "tokio"))
+    not(any(feature = "async-std", feature = "tokio", feature = "smol"))
 ))]
 criterion_main!(benches, link_to_benches);
 #[cfg(all(
     not(feature = "link_to"),
-    any(feature = "async-std", feature = "tokio")
+    any(feature = "async-std", feature = "tokio", feature = "smol")
 ))]
 criterion_main!(benches, benches_async);
-#[cfg(all(feature = "link_to", any(feature = "async-std", feature = "tokio")))]
+#[cfg(all(
+    feature = "link_to",
+    any(feature = "async-std", feature = "tokio", feature = "smol")
+))]
 criterion_main!(
     benches,
     benches_async,
@@ -443,6 +463,6 @@ criterion_main!(
 );
 #[cfg(all(
     not(feature = "link_to"),
-    not(any(feature = "async-std", feature = "tokio"))
+    not(any(feature = "async-std", feature = "tokio", feature = "smol"))
 ))]
 criterion_main!(benches);

justfile

@@ -2,26 +2,32 @@
 @help:
     just -l
 
-# Run tests on both runtimes with cargo nextest
+# Run tests on all runtimes with cargo nextest
 @test:
     echo "----------\nasync-std:\n"
     cargo nextest run
     echo "\n----------\ntokio:\n"
     cargo nextest run --no-default-features --features tokio-runtime
+    echo "\n----------\nsmol:\n"
+    cargo nextest run --no-default-features --features smol-runtime
 
 # Run benchmarks with `cargo bench`
 @bench:
     echo "----------\nasync-std:\n"
     cargo bench
     echo "\n----------\ntokio:\n"
     cargo bench --no-default-features --features tokio-runtime
+    echo "\n----------\nsmol:\n"
+    cargo bench --no-default-features --features smol-runtime
 
 # Run benchmarks with `cargo criterion`
 @criterion:
     echo "----------\nasync-std:\n"
     cargo criterion
     echo "\n----------\ntokio:\n"
     cargo criterion --no-default-features --features tokio-runtime
+    echo "\n----------\nsmol:\n"
+    cargo criterion --no-default-features --features smol-runtime
 
 # Generate a changelog with git-cliff
 changelog TAG:

src/async_lib.rs

@@ -1,75 +1,105 @@
 #[cfg(feature = "async-std")]
 pub use async_std::fs::File;
+#[cfg(feature = "smol")]
+pub use smol::fs::File;
 #[cfg(feature = "tokio")]
 pub use tokio::fs::File;
 
 #[cfg(feature = "async-std")]
 pub use futures::io::AsyncRead;
+#[cfg(feature = "smol")]
+pub use futures::io::AsyncRead;
 #[cfg(feature = "tokio")]
 pub use tokio::io::AsyncRead;
 
 #[cfg(feature = "async-std")]
 pub use futures::io::AsyncReadExt;
+#[cfg(feature = "smol")]
+pub use futures::io::AsyncReadExt;
 #[cfg(feature = "tokio")]
 pub use tokio::io::AsyncReadExt;
 
 #[cfg(feature = "async-std")]
 pub use futures::io::AsyncBufReadExt;
+#[cfg(feature = "smol")]
+pub use futures::io::AsyncBufReadExt;
 #[cfg(feature = "tokio")]
 pub use tokio::io::AsyncBufReadExt;
 
 #[cfg(feature = "async-std")]
 pub use futures::io::AsyncWrite;
+#[cfg(feature = "smol")]
+pub use futures::io::AsyncWrite;
 #[cfg(feature = "tokio")]
 pub use tokio::io::AsyncWrite;
 
 #[cfg(feature = "async-std")]
 pub use futures::io::AsyncWriteExt;
+#[cfg(feature = "smol")]
+pub use futures::io::AsyncWriteExt;
 #[cfg(feature = "tokio")]
 pub use tokio::io::AsyncWriteExt;
 
 #[cfg(feature = "async-std")]
 pub use async_std::fs::read;
+#[cfg(feature = "smol")]
+pub use smol::fs::read;
 #[cfg(feature = "tokio")]
 pub use tokio::fs::read;
 
 #[cfg(feature = "async-std")]
 pub use async_std::fs::copy;
+#[cfg(feature = "smol")]
+pub use smol::fs::copy;
 #[cfg(feature = "tokio")]
 pub use tokio::fs::copy;
 
 #[cfg(feature = "async-std")]
 pub use async_std::fs::metadata;
+#[cfg(feature = "smol")]
+pub use smol::fs::metadata;
 #[cfg(feature = "tokio")]
 pub use tokio::fs::metadata;
 
 #[cfg(feature = "async-std")]
 pub use async_std::fs::remove_file;
+#[cfg(feature = "smol")]
+pub use smol::fs::remove_file;
 #[cfg(feature = "tokio")]
 pub use tokio::fs::remove_file;
 
 #[cfg(feature = "async-std")]
 pub use async_std::fs::create_dir_all;
+#[cfg(feature = "smol")]
+pub use smol::fs::create_dir_all;
 #[cfg(feature = "tokio")]
 pub use tokio::fs::create_dir_all;
 
 #[cfg(feature = "async-std")]
 pub use async_std::fs::remove_dir_all;
+#[cfg(feature = "smol")]
+pub use smol::fs::remove_dir_all;
 #[cfg(feature = "tokio")]
 pub use tokio::fs::remove_dir_all;
 
 #[cfg(feature = "async-std")]
 pub use async_std::fs::DirBuilder;
+#[cfg(feature = "smol")]
+pub use smol::fs::DirBuilder;
 #[cfg(feature = "tokio")]
 pub use tokio::fs::DirBuilder;
 
 #[cfg(feature = "async-std")]
 pub use async_std::fs::OpenOptions;
+#[cfg(feature = "smol")]
+pub use smol::fs::OpenOptions;
 #[cfg(feature = "tokio")]
 pub use tokio::fs::OpenOptions;
 
 #[cfg(feature = "async-std")]
 pub use async_std::io::BufReader;
+#[cfg(feature = "smol")]
+pub use futures::io::BufReader;
 #[cfg(feature = "tokio")]
 pub use tokio::io::BufReader;
 
@@ -83,9 +113,16 @@ pub fn lines_to_stream<R>(lines: futures::io::Lines<R>) -> futures::io::Lines<R>
 pub fn lines_to_stream<R>(lines: tokio::io::Lines<R>) -> tokio_stream::wrappers::LinesStream<R> {
     tokio_stream::wrappers::LinesStream::new(lines)
 }
+#[cfg(feature = "smol")]
+#[inline]
+pub fn lines_to_stream<R>(lines: futures::io::Lines<R>) -> futures::io::Lines<R> {
+    lines
+}
 
 #[cfg(feature = "async-std")]
 pub use async_std::task::spawn_blocking;
+#[cfg(feature = "smol")]
+pub use smol::unblock as spawn_blocking;
 #[cfg(feature = "tokio")]
 pub use tokio::task::spawn_blocking;
 
@@ -103,6 +140,13 @@ pub use tokio::task::JoinHandle;
 pub fn unwrap_joinhandle_value<T>(value: T) -> T {
     value
 }
+#[cfg(feature = "smol")]
+pub use smol::Task as JoinHandle;
+#[cfg(feature = "smol")]
+#[inline]
+pub fn unwrap_joinhandle_value<T>(value: T) -> T {
+    value
+}
 
 use tempfile::NamedTempFile;
 
@@ -135,3 +179,17 @@ pub async fn create_named_tempfile(
         _ => None,
     }
 }
+
+#[cfg(feature = "smol")]
+#[inline]
+pub async fn create_named_tempfile(
+    tmp_path: std::path::PathBuf,
+) -> Option<crate::Result<NamedTempFile>> {
+    let cloned = tmp_path.clone();
+
+    Some(
+        spawn_blocking(|| NamedTempFile::new_in(tmp_path))
+            .await
+            .with_context(|| format!("Failed to create a temp file at {}", cloned.display())),
+    )
+}