Forbid uses of unwrap() in the code (#7795)

crates/egui_demo_app/src/apps/custom3d_wgpu.rs

@@ -1,3 +1,5 @@
+#![expect(clippy::unwrap_used)] // TODO(emilk): avoid unwraps
+
 use std::num::NonZeroU64;
 
 use eframe::{

crates/egui_demo_app/src/backend_panel.rs

@@ -459,11 +459,13 @@ fn call_after_delay(delay: std::time::Duration, f: impl FnOnce() + Send + 'stati
             std::thread::sleep(delay);
             f();
         })
-        .unwrap();
+        .expect("Failed to spawn a thread");
 }
 
 #[cfg(target_arch = "wasm32")]
 fn call_after_delay(delay: std::time::Duration, f: impl FnOnce() + Send + 'static) {
+    #![expect(clippy::unwrap_used)]
+
     use wasm_bindgen::prelude::*;
     let window = web_sys::window().unwrap();
     let closure = Closure::once(f);

crates/egui_demo_app/src/lib.rs

@@ -1,5 +1,4 @@
 //! Demo app for egui
-#![allow(clippy::missing_errors_doc)]
 
 mod apps;
 mod backend_panel;

crates/egui_demo_app/src/web.rs

@@ -31,6 +31,9 @@ impl WebHandle {
     }
 
     /// Call this once from JavaScript to start your app.
+    ///
+    /// # Errors
+    /// Returns an error if the app could not start.
     #[wasm_bindgen]
     pub async fn start(
         &self,