feat: Add assert for public types to ensure Send + Sync (#2237)

feat: Add assert for public types to make sure Send + Sync

Signed-off-by: Xuanwo <github@xuanwo.io>

core/src/lib.rs

@@ -94,4 +94,18 @@ mod tests {
         assert_eq!(1, size_of::<EntryMode>());
         assert_eq!(24, size_of::<Scheme>());
     }
+
+    /// This is used to make sure our public API implement Send + Sync
+    trait AssertSendSync: Send + Sync {}
+    impl AssertSendSync for Entry {}
+    impl AssertSendSync for Capability {}
+    impl AssertSendSync for Error {}
+    impl AssertSendSync for Reader {}
+    impl AssertSendSync for Writer {}
+    impl AssertSendSync for Lister {}
+    impl AssertSendSync for Operator {}
+    impl AssertSendSync for BlockingReader {}
+    impl AssertSendSync for BlockingWriter {}
+    impl AssertSendSync for BlockingLister {}
+    impl AssertSendSync for BlockingOperator {}
 }

core/src/raw/oio/page.rs

@@ -96,7 +96,7 @@ impl<P: Page> Page for Option<P> {
 }
 
 /// BlockingPage is the blocking version of [`Page`].
-pub trait BlockingPage: 'static {
+pub trait BlockingPage: Send + 'static {
     /// Fetch a new page of [`Entry`]
     ///
     /// `Ok(None)` means all pages have been returned. Any following call

core/src/types/list.rs

@@ -47,6 +47,11 @@ pub struct Lister {
     fut: Option<BoxFuture<'static, (oio::Pager, Result<Option<Vec<oio::Entry>>>)>>,
 }
 
+/// # Safety
+///
+/// Lister will only be accessed by `&mut Self`
+unsafe impl Sync for Lister {}
+
 impl Lister {
     /// Create a new lister.
     pub(crate) fn new(pager: oio::Pager) -> Self {
@@ -166,6 +171,11 @@ pub struct BlockingLister {
     buf: VecDeque<oio::Entry>,
 }
 
+/// # Safety
+///
+/// BlockingLister will only be accessed by `&mut Self`
+unsafe impl Sync for BlockingLister {}
+
 impl BlockingLister {
     /// Create a new lister.
     pub(crate) fn new(pager: oio::BlockingPager) -> Self {

core/src/types/writer.rs

@@ -58,6 +58,11 @@ pub struct Writer {
     state: State,
 }
 
+/// # Safety
+///
+/// Writer will only be accessed by `&mut Self`
+unsafe impl Sync for Writer {}
+
 impl Writer {
     /// Create a new writer.
     ///