add regression tests for 4492 and 3868

examples/regression/Cargo.toml

@@ -17,7 +17,7 @@ leptos_router = { path = "../../router" }
 serde = { version = "1.0", features = ["derive"] }
 thiserror = "2.0.12"
 tokio = { version = "1.39", features = [ "rt-multi-thread", "macros", "time" ], optional = true }
-wasm-bindgen = "0.2.92"
+wasm-bindgen = "0.2.106"
 
 [features]
 hydrate = [

examples/regression/e2e/features/issue_4492.feature

@@ -0,0 +1,38 @@
+@check_issue_4492
+Feature: Regression test for issue #4492
+
+	Scenario: Scenario A should show Loading once on first load.
+		Given I see the app
+		And I can access regression test 4492
+		When I click the button a-toggle
+		Then I see a-result has the text Loading...
+		When I wait 100ms
+		Then I see a-result has the text 0
+		When I click the button a-button
+		Then I see a-result has the text 0
+		When I wait 100ms
+		Then I see a-result has the text 1
+
+	Scenario: Scenario B should never show Loading
+		Given I see the app
+		And I can access regression test 4492
+		When I click the button b-toggle
+		Then I see b-result has the text 0
+		When I click the button b-button
+		Then I see b-result has the text 0
+		When I wait 100ms
+		Then I see b-result has the text 1
+		When I click the button b-button
+		Then I see b-result has the text 1
+		When I wait 100ms
+		Then I see b-result has the text 2
+
+	Scenario: Scenario C should never show Loading
+		Given I see the app
+		And I can access regression test 4492
+		When I click the button c-toggle
+		Then I see c-result has the text 0
+		When I click the button c-button
+		Then I see c-result has the text 0
+		When I wait 100ms
+		Then I see c-result has the text 1

examples/regression/e2e/tests/fixtures/action.rs

@@ -15,3 +15,9 @@ pub async fn click_link(client: &Client, text: &str) -> Result<()> {
     link.click().await?;
     Ok(())
 }
+
+pub async fn click_button(client: &Client, id: &str) -> Result<()> {
+    let btn = find::element_by_id(&client, &id).await?;
+    btn.click().await?;
+    Ok(())
+}

examples/regression/e2e/tests/fixtures/check.rs

@@ -7,7 +7,15 @@ pub async fn result_text_is(
     client: &Client,
     expected_text: &str,
 ) -> Result<()> {
-    let actual = find::text_at_id(client, "result").await?;
+    element_text_is(client, "result", expected_text).await
+}
+
+pub async fn element_text_is(
+    client: &Client,
+    id: &str,
+    expected_text: &str,
+) -> Result<()> {
+    let actual = find::text_at_id(client, id).await?;
     assert_eq!(&actual, expected_text);
     Ok(())
 }

examples/regression/e2e/tests/fixtures/world/action_steps.rs

@@ -20,6 +20,14 @@ async fn i_select_the_link(world: &mut AppWorld, text: String) -> Result<()> {
     Ok(())
 }
 
+#[when(regex = "^I click the button (.*)$")]
+async fn i_click_the_button(world: &mut AppWorld, id: String) -> Result<()> {
+    let client = &world.client;
+    action::click_button(client, &id).await?;
+
+    Ok(())
+}
+
 #[given(expr = "I select the following links")]
 #[when(expr = "I select the following links")]
 async fn i_select_the_following_links(
@@ -54,3 +62,10 @@ async fn i_go_back(world: &mut AppWorld) -> Result<()> {
 
     Ok(())
 }
+
+#[when(regex = r"^I wait (\d+)ms$")]
+async fn i_wait_ms(_world: &mut AppWorld, ms: u64) -> Result<()> {
+    tokio::time::sleep(std::time::Duration::from_millis(ms)).await;
+
+    Ok(())
+}

examples/regression/e2e/tests/fixtures/world/check_steps.rs

@@ -19,6 +19,17 @@ async fn i_see_the_result_is_the_string(
     Ok(())
 }
 
+#[then(regex = r"^I see ([\w-]+) has the text (.*)$")]
+async fn i_see_element_has_text(
+    world: &mut AppWorld,
+    id: String,
+    text: String,
+) -> Result<()> {
+    let client = &world.client;
+    check::element_text_is(client, &id, &text).await?;
+    Ok(())
+}
+
 #[then(regex = r"^I see the navbar$")]
 async fn i_see_the_navbar(world: &mut AppWorld) -> Result<()> {
     let client = &world.client;

examples/regression/src/app.rs

@@ -1,7 +1,7 @@
 use crate::{
     issue_4005::Routes4005, issue_4088::Routes4088, issue_4217::Routes4217,
     issue_4285::Routes4285, issue_4296::Routes4296, issue_4324::Routes4324,
-    pr_4015::Routes4015, pr_4091::Routes4091,
+    issue_4492::Routes4492, pr_4015::Routes4015, pr_4091::Routes4091,
 };
 use leptos::prelude::*;
 use leptos_meta::{MetaTags, *};
@@ -48,6 +48,7 @@ pub fn App() -> impl IntoView {
                     <Routes4285/>
                     <Routes4296/>
                     <Routes4324/>
+                    <Routes4492/>
                 </Routes>
             </main>
         </Router>
@@ -75,6 +76,7 @@ fn HomePage() -> impl IntoView {
                 <li><a href="/4285/">"4285"</a></li>
                 <li><a href="/4296/">"4296"</a></li>
                 <li><a href="/4324/">"4324"</a></li>
+                <li><a href="/4492/">"4492"</a></li>
             </ul>
         </nav>
     }

examples/regression/src/issue_4492.rs

@@ -0,0 +1,114 @@
+use leptos::prelude::*;
+#[allow(unused_imports)]
+use leptos_router::{
+    components::Route, path, MatchNestedRoutes, NavigateOptions,
+};
+
+#[component]
+pub fn Routes4492() -> impl MatchNestedRoutes + Clone {
+    view! {
+        <Route path=path!("4492") view=Issue4492/>
+    }
+    .into_inner()
+}
+
+#[component]
+fn Issue4492() -> impl IntoView {
+    let show_a = RwSignal::new(false);
+    let show_b = RwSignal::new(false);
+    let show_c = RwSignal::new(false);
+
+    view! {
+        <button id="a-toggle" on:click=move |_| show_a.set(!show_a.get())>"Toggle A"</button>
+        <button id="b-toggle" on:click=move |_| show_b.set(!show_b.get())>"Toggle B"</button>
+        <button id="c-toggle" on:click=move |_| show_c.set(!show_c.get())>"Toggle C"</button>
+
+        <Show when=move || show_a.get()>
+            <ScenarioA/>
+        </Show>
+        <Show when=move || show_b.get()>
+            <ScenarioB/>
+        </Show>
+        <Show when=move || show_c.get()>
+            <ScenarioC/>
+        </Show>
+    }
+}
+
+#[component]
+fn ScenarioA() -> impl IntoView {
+    // scenario A: one truly-async resource is read on click
+    let counter = RwSignal::new(0);
+    let resource = Resource::new(
+        move || counter.get(),
+        |count| async move {
+            sleep(50).await.unwrap();
+            count
+        },
+    );
+    view! {
+        <Transition fallback=|| view! { <p id="a-result">"Loading..."</p> }>
+            <p id="a-result">{resource}</p>
+        </Transition>
+        <button id="a-button" on:click=move |_| *counter.write() += 1>"+1"</button>
+    }
+}
+
+#[component]
+fn ScenarioB() -> impl IntoView {
+    // scenario B: resource immediately available first time, then after 250ms
+    let counter = RwSignal::new(0);
+    let resource = Resource::new(
+        move || counter.get(),
+        |count| async move {
+            if count == 0 {
+                count
+            } else {
+                sleep(50).await.unwrap();
+                count
+            }
+        },
+    );
+    view! {
+        <Transition fallback=|| view! { <p id="b-result">"Loading..."</p> }>
+            <p id="b-result">{resource}</p>
+        </Transition>
+        <button id="b-button" on:click=move |_| *counter.write() += 1>"+1"</button>
+    }
+}
+
+#[component]
+fn ScenarioC() -> impl IntoView {
+    // scenario C: not even a resource on the first run, just a value
+    // see https://github.com/leptos-rs/leptos/issues/3868
+    let counter = RwSignal::new(0);
+    let s_res = StoredValue::new(None::<ArcLocalResource<i32>>);
+    let resource = move || {
+        let count = counter.get();
+        if count == 0 {
+            count
+        } else {
+            let r = s_res.get_value().unwrap_or_else(|| {
+                let res = ArcLocalResource::new(move || async move {
+                    sleep(50).await.unwrap();
+                    count
+                });
+                s_res.set_value(Some(res.clone()));
+                res
+            });
+            r.get().unwrap_or(42)
+        }
+    };
+    view! {
+        <Transition fallback=|| view! { <p id="c-result">"Loading..."</p> }>
+            <p id="c-result">{resource}</p>
+        </Transition>
+        <button id="c-button" on:click=move |_| *counter.write() += 1>"+1"</button>
+    }
+}
+
+#[server]
+async fn sleep(ms: u64) -> Result<(), ServerFnError> {
+    tokio::time::sleep(std::time::Duration::from_millis(ms)).await;
+    Ok(())
+}

examples/regression/src/lib.rs

@@ -5,6 +5,7 @@ mod issue_4217;
 mod issue_4285;
 mod issue_4296;
 mod issue_4324;
+mod issue_4492;
 mod pr_4015;
 mod pr_4091;