use_future takes a closure

yewstack · Apr 14, 2022 · 48eb65f · 48eb65f
1 parent 5fec29a
commit 48eb65f
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Showing 2 changed files with 36 additions and 6 deletions.
diff --git a/packages/yew/src/suspense/hooks.rs b/packages/yew/src/suspense/hooks.rs
@@ -1,7 +1,9 @@
 #[cfg_attr(documenting, doc(cfg(any(target_arch = "wasm32", feature = "tokio"))))]
 #[cfg(any(target_arch = "wasm32", feature = "tokio"))]
 mod feat_futures {
+    use std::fmt;
     use std::future::Future;
+    use std::ops::Deref;
 
     use yew::prelude::*;
     use yew::suspense::{Suspension, SuspensionResult};
@@ -10,22 +12,50 @@ mod feat_futures {
     ///
     /// A [Suspension] is created from the passed future and the result of the future
     /// is the output of the suspension.
+    pub struct UseFutureHandle<O> {
+        inner: UseStateHandle<Option<O>>,
+    }
+
+    impl<O> Deref for UseFutureHandle<O> {
+        type Target = O;
+
+        fn deref(&self) -> &Self::Target {
+            &*self.inner.as_ref().unwrap()
+        }
+    }
+
+    impl<T: fmt::Debug> fmt::Debug for UseFutureHandle<T> {
+        fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+            f.debug_struct("UseFutureHandle")
+                .field("value", &format!("{:?}", self.inner))
+                .finish()
+        }
+    }
+
     #[hook]
-    pub fn use_future<T, F>(f: F) -> SuspensionResult<T>
+    pub fn use_future<F, T, O>(f: F) -> SuspensionResult<UseFutureHandle<O>>
     where
-        T: Clone + 'static,
-        F: Future<Output = T> + 'static,
+        F: FnOnce() -> T + 'static,
+        T: Future<Output = O> + 'static,
+        O: 'static,
     {
         let output = use_state(|| None);
 
         let suspension = {
             let output = output.clone();
 
-            use_state(move || Suspension::from_future(async move { output.set(Some(f.await)) }))
+            use_memo(
+                move |_| {
+                    Suspension::from_future(async move {
+                        output.set(Some(f().await));
+                    })
+                },
+                (),
+            )
         };
 
         if suspension.resumed() {
-            Ok((*output).clone().unwrap())
+            Ok(UseFutureHandle { inner: output })
         } else {
             Err((*suspension).clone())
         }

diff --git a/packages/yew/tests/suspense.rs b/packages/yew/tests/suspense.rs
@@ -598,7 +598,7 @@ async fn effects_not_run_when_suspended() {
 async fn use_suspending_future_works() {
     #[function_component(Content)]
     fn content() -> HtmlResult {
-        let _sleep_handle = use_future(async move {
+        let _sleep_handle = use_future(|| async move {
             TimeoutFuture::new(50).await;
         })?;