Catch 5813 and avoid crash (#6585)

app/gui/view/documentation/src/html.rs

@@ -63,16 +63,29 @@ fn svg_icon(content: &'static str) -> impl Render {
 /// Render entry documentation to HTML code with Tailwind CSS styles.
 #[profile(Detail)]
 pub fn render(docs: EntryDocumentation) -> String {
-    match docs {
+    let html = match docs {
         EntryDocumentation::Placeholder(placeholder) => match placeholder {
             Placeholder::NoDocumentation => String::from("No documentation available."),
             Placeholder::VirtualComponentGroup { name } =>
                 render_virtual_component_group_docs(name),
         },
         EntryDocumentation::Docs(docs) => render_documentation(docs),
+    };
+    match validate_utf8(&html) {
+        Ok(_) => html,
+        Err(_) => {
+            error!("Internal error. Generated HTML is not valid utf-8. This is bug #5813.");
+            String::from("Failed to load documentation.")
+        }
     }
 }
 
+#[profile(Debug)]
+fn validate_utf8(s: &str) -> Result<&str, std::str::Utf8Error> {
+    let bytes = s.as_bytes();
+    std::str::from_utf8(bytes)
+}
+
 fn render_documentation(docs: Documentation) -> String {
     match docs {
         Documentation::Module(module_docs) => render_module_documentation(&module_docs, None),

app/gui/view/documentation/src/lib.rs

@@ -18,21 +18,12 @@
 //! [`Tailwind CSS`]: https://tailwindcss.com/
 
 // === Features ===
-#![feature(associated_type_bounds)]
-#![feature(associated_type_defaults)]
 #![feature(drain_filter)]
-#![feature(fn_traits)]
 #![feature(option_result_contains)]
-#![feature(specialization)]
-#![feature(trait_alias)]
-#![feature(type_alias_impl_trait)]
-#![feature(unboxed_closures)]
 // === Standard Linter Configuration ===
 #![deny(non_ascii_idents)]
-#![warn(unsafe_code)]
 #![allow(clippy::bool_to_int_with_if)]
 #![allow(clippy::let_and_return)]
-#![allow(incomplete_features)] // To be removed, see: https://github.com/enso-org/ide/issues/1559
 #![warn(missing_copy_implementations)]
 #![warn(missing_debug_implementations)]
 #![warn(missing_docs)]
@@ -64,10 +55,8 @@ use ensogl::Animation;
 use ensogl_component::shadow;
 use ensogl_derive_theme::FromTheme;
 use ensogl_hardcoded_theme::application::component_browser::documentation as theme;
-use web::Closure;
 use web::HtmlElement;
 use web::JsCast;
-use web::MouseEvent;
 
 pub mod html;
 
@@ -89,6 +78,7 @@ const MIN_CAPTION_HEIGHT: f32 = 1.0;
 /// Delay before updating the displayed documentation.
 const DISPLAY_DELAY_MS: i32 = 0;
 
+
 // === Style ===
 
 #[derive(Debug, Clone, Copy, Default, FromTheme)]
@@ -108,24 +98,20 @@ pub struct Style {
 // === Model ===
 // =============
 
-type CodeCopyClosure = Closure<dyn FnMut(MouseEvent)>;
-
 /// Model of Native visualization that generates documentation for given Enso code and embeds
 /// it in a HTML container.
 #[derive(Clone, CloneRef, Debug)]
 #[allow(missing_docs)]
 pub struct Model {
-    outer_dom:          DomSymbol,
-    caption_dom:        DomSymbol,
-    inner_dom:          DomSymbol,
+    outer_dom:      DomSymbol,
+    caption_dom:    DomSymbol,
+    inner_dom:      DomSymbol,
     /// The purpose of this overlay is stop propagating mouse events under the documentation panel
     /// to EnsoGL shapes, and pass them to the DOM instead.
-    overlay:            overlay::View,
-    display_object:     display::object::Instance,
-    code_copy_closures: Rc<CloneCell<Vec<CodeCopyClosure>>>,
+    overlay:        overlay::View,
+    display_object: display::object::Instance,
 }
 
-
 impl Model {
     /// Constructor.
     fn new(scene: &Scene) -> Self {
@@ -164,9 +150,7 @@ impl Model {
         scene.dom.layers.node_searcher.manage(&inner_dom);
         scene.dom.layers.node_searcher.manage(&caption_dom);
 
-        let code_copy_closures = default();
-        Model { outer_dom, inner_dom, caption_dom, overlay, display_object, code_copy_closures }
-            .init()
+        Model { outer_dom, inner_dom, caption_dom, overlay, display_object }.init()
     }
 
     fn init(self) -> Self {