refactor(v0): render page swap with hemplate

Move the v0 docs/page-swap partial and EffectBatch content payload from raw HTML strings into hemplate views, with scraper assertions for rendered structure.

req: html_safety/002

req: view/001

req: test/005

examples/v0/src/main.rs

@@ -37,6 +37,18 @@ struct TodoItem {
     title: String,
 }
 
+#[derive(Hemplate)]
+struct PageSwap {
+    content: SafeHtml,
+    title: &'static str,
+}
+
+#[derive(Hemplate)]
+#[hemplate = "partials"]
+struct DocsContent {
+    message: &'static str,
+}
+
 #[tokio::main]
 async fn main() {
     let state = Arc::new(ExampleState::default());
@@ -63,16 +75,7 @@ async fn home(request: PageRequest) -> impl IntoResponse {
 
 // req: page_swap/002, req: examples/001
 async fn docs(request: PageRequest) -> impl IntoResponse {
-    let partial = ui::page_swap::lower_html(
-        r#"<main data-slhx-root="docs">
-  <nav data-slhx-slot="nav">
-    <a href="/" data-slhx-nav="">Examples</a>
-    <a href="/docs" data-slhx-nav="">Docs</a>
-  </nav>
-  <article data-slhx-slot="content"><h1>Docs</h1><p>This page was swapped without a full reload.</p></article>
-  <title data-slhx-slot="title">Docs</title>
-</main>"#,
-    );
+    let partial = render_page_swap("Docs", "This page was swapped without a full reload.");
     request
         .page(partial, shell)
         .title("Docs")
@@ -155,8 +158,8 @@ fn registry(state: Arc<ExampleState>) -> HandlerRegistry {
         .register(ui::page_swap::handles::load_docs.id().id, |_| {
             // req: page_swap/002, req: examples/001
             (
-                ui::page_swap::slots::content.html(SafeHtml::trusted(
-                    "<h1>Docs</h1><p>This content came from an EffectBatch.</p>",
+                ui::page_swap::slots::content.html(render_docs_content(
+                    "This content came from an EffectBatch.",
                 )),
                 ui::page_swap::slots::title.text("Docs"),
                 push("/docs"),
@@ -170,7 +173,7 @@ fn all_examples() -> String {
         ui::todos::lower_html(include_str!("../templates/todos.heml")),
         ui::wizard::lower_html(include_str!("../templates/wizard.heml")),
         ui::auth::lower_html(include_str!("../templates/auth.heml")),
-        ui::page_swap::lower_html(include_str!("../templates/page_swap.heml")),
+        render_page_swap("Welcome", "Welcome"),
         ui::notifications::lower_html(include_str!("../templates/notifications.heml")),
     ]
     .join("\n")
@@ -214,8 +217,25 @@ fn render_todos(todos: &[Todo]) -> SafeHtml {
     })
 }
 
+fn render_page_swap(title: &'static str, message: &'static str) -> String {
+    // req: html_safety/002 req: view/001
+    ui::page_swap::lower_html(render_template(&PageSwap {
+        content: render_docs_content(message),
+        title,
+    }))
+}
+
+fn render_docs_content(message: &'static str) -> SafeHtml {
+    // req: html_safety/002 req: view/001
+    render_html(&DocsContent { message })
+}
+
 fn render_html(template: &impl Hemplate) -> SafeHtml {
-    SafeHtml::trusted(template.render().expect("v0 hemplate partial renders"))
+    SafeHtml::trusted(render_template(template))
+}
+
+fn render_template(template: &impl Hemplate) -> String {
+    template.render().expect("v0 hemplate view renders")
 }
 
 #[cfg(test)]
@@ -227,6 +247,43 @@ mod tests {
         Selector::parse(value).expect("test selector parses")
     }
 
+    // req: html_safety/002 req: view/001 req: test/005
+    #[test]
+    fn docs_content_payload_is_rendered_by_a_hemplate_view() {
+        let html = render_docs_content("This content came from an EffectBatch.");
+        let document = Html::parse_fragment(html.as_str());
+        assert_eq!(
+            document
+                .select(&selector("h1"))
+                .next()
+                .map(|heading| heading.text().collect::<String>()),
+            Some("Docs".to_owned())
+        );
+        assert_eq!(
+            document
+                .select(&selector("p"))
+                .next()
+                .map(|paragraph| paragraph.text().collect::<String>()),
+            Some("This content came from an EffectBatch.".to_owned())
+        );
+    }
+
+    // req: html_safety/002 req: view/001 req: test/005
+    #[test]
+    fn docs_page_partial_is_rendered_by_a_hemplate_view() {
+        let html = render_page_swap("Docs", "This page was swapped without a full reload.");
+        let document = Html::parse_fragment(&html);
+        assert_eq!(document.select(&selector("main[data-slhx-root=\"docs\"]")).count(), 1);
+        assert_eq!(document.select(&selector("article[data-sid]")).count(), 1);
+        assert_eq!(
+            document
+                .select(&selector("article h1"))
+                .next()
+                .map(|heading| heading.text().collect::<String>()),
+            Some("Docs".to_owned())
+        );
+    }
+
     // req: html_safety/002 req: view/001 req: test/005
     #[test]
     fn todos_payload_is_rendered_by_a_hemplate_view() {

examples/v0/templates/page_swap.heml

@@ -2,6 +2,6 @@
   <nav data-slhx-slot="nav">
     <a href="/docs" data-slhx-nav="" data-slhx-handle="load_docs">Docs</a>
   </nav>
-  <article data-slhx-slot="content">Welcome</article>
-  <title data-slhx-slot="title">Welcome</title>
+  <article data-slhx-slot="content">{+= self.content =+}</article>
+  <title data-slhx-slot="title">{+ self.title +}</title>
 </main>

examples/v0/templates/partials/docs_content.heml

@@ -0,0 +1 @@
+<h1>Docs</h1><p>{+ self.message +}</p>