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

Cargo.toml

@@ -340,6 +340,7 @@ unused_peekable = "warn"
 unused_rounding = "warn"
 unused_self = "warn"
 unused_trait_names = "warn"
+unwrap_used = "warn"
 use_self = "warn"
 useless_let_if_seq = "warn"
 useless_transmute = "warn"
@@ -352,7 +353,6 @@ zero_sized_map_values = "warn"
 comparison_chain = "allow"
 should_panic_without_expect = "allow"
 too_many_lines = "allow"
-unwrap_used = "allow" # TODO(emilk): We really wanna warn on this one
 
 # These are meh:
 assigning_clones = "allow" # No please

crates/eframe/src/epi.rs

@@ -791,6 +791,7 @@ impl Frame {
     /// This function will take the ownership of your [`glow::Texture`], so please do not delete your [`glow::Texture`] after registering.
     #[cfg(all(feature = "glow", not(target_arch = "wasm32")))]
     pub fn register_native_glow_texture(&mut self, native: glow::Texture) -> egui::TextureId {
+        #[expect(clippy::unwrap_used)]
         self.glow_register_native_texture.as_mut().unwrap()(native)
     }
 

crates/eframe/src/native/epi_integration.rs

@@ -376,6 +376,7 @@ impl EpiIntegration {
 
 fn load_default_egui_icon() -> egui::IconData {
     profiling::function_scope!();
+    #[expect(clippy::unwrap_used)]
     crate::icon_data::from_png_bytes(&include_bytes!("../../data/icon.png")[..]).unwrap()
 }
 

crates/eframe/src/native/glow_integration.rs

@@ -5,7 +5,8 @@
 //! There is a bunch of improvements we could do,
 //! like removing a bunch of `unwraps`.
 
-#![allow(clippy::undocumented_unsafe_blocks)]
+#![expect(clippy::undocumented_unsafe_blocks)]
+#![expect(clippy::unwrap_used)]
 
 use std::{cell::RefCell, num::NonZeroU32, rc::Rc, sync::Arc, time::Instant};
 

crates/eframe/src/native/winit_integration.rs

@@ -27,7 +27,10 @@ pub fn create_egui_context(storage: Option<&dyn crate::Storage>) -> egui::Contex
 
     egui_ctx.options_mut(|o| {
         // eframe supports multi-pass (Context::request_discard).
+        #[expect(clippy::unwrap_used)]
+        {
             o.max_passes = 2.try_into().unwrap();
+        }
     });
 
     let memory = crate::native::epi_integration::load_egui_memory(storage).unwrap_or_default();

crates/eframe/src/stopwatch.rs

@@ -23,7 +23,7 @@ impl Stopwatch {
     }
 
     pub fn pause(&mut self) {
-        let start = self.start.take().unwrap();
+        let start = self.start.take().expect("Stopwatch is not running");
         let duration = start.elapsed();
         self.total_time_ns += duration.as_nanos();
     }

crates/eframe/src/web/mod.rs

@@ -1,6 +1,7 @@
 //! [`egui`] bindings for web apps (compiling to WASM).
 
-#![allow(clippy::missing_errors_doc)] // So many `-> Result<_, JsValue>`
+#![expect(clippy::missing_errors_doc)] // So many `-> Result<_, JsValue>`
+#![expect(clippy::unwrap_used)] // TODO(emilk): remove unwraps
 
 mod app_runner;
 mod backend;

crates/egui-wgpu/src/renderer.rs

@@ -1,4 +1,4 @@
-#![allow(unsafe_code)]
+#![expect(clippy::unwrap_used)] // TODO(emilk): avoid unwraps
 
 use std::{borrow::Cow, num::NonZeroU64, ops::Range};
 

crates/egui-wgpu/src/winit.rs

@@ -1,5 +1,6 @@
-#![allow(clippy::missing_errors_doc)]
-#![allow(clippy::undocumented_unsafe_blocks)]
+#![expect(clippy::missing_errors_doc)]
+#![expect(clippy::undocumented_unsafe_blocks)]
+#![expect(clippy::unwrap_used)] // TODO(emilk): avoid unwraps
 
 use crate::{RenderState, SurfaceErrorAction, WgpuConfiguration, renderer};
 use crate::{

crates/egui/src/cache/cache_storage.rs

@@ -28,6 +28,7 @@ pub struct CacheStorage {
 
 impl CacheStorage {
     pub fn cache<Cache: CacheTrait + Default>(&mut self) -> &mut Cache {
+        #[expect(clippy::unwrap_used)]
         self.caches
             .entry(std::any::TypeId::of::<Cache>())
             .or_insert_with(|| Box::<Cache>::default())

crates/egui/src/containers/area.rs

@@ -722,6 +722,7 @@ fn automatic_area_position(ctx: &Context, constrain_rect: Rect, layer_id: LayerI
     let mut column_bbs = vec![existing[0]];
 
     for &rect in &existing {
+        #[expect(clippy::unwrap_used)]
         let current_column_bb = column_bbs.last_mut().unwrap();
         if rect.left() < current_column_bb.right() {
             // same column
@@ -752,6 +753,7 @@ fn automatic_area_position(ctx: &Context, constrain_rect: Rect, layer_id: LayerI
     }
 
     // Maybe we can fit a new column?
+    #[expect(clippy::unwrap_used)]
     let rightmost = column_bbs.last().unwrap().right();
     if rightmost + 200.0 < constrain_rect.right() {
         return pos2(rightmost + spacing, top);

crates/egui/src/containers/menu.rs

@@ -444,11 +444,8 @@ impl SubMenu {
         let mut menu_config = self.config.unwrap_or_else(|| parent_config.clone());
         menu_config.bar = false;
 
-        let menu_root_response = ui
-            .ctx()
-            .read_response(menu_id)
-            // Since we are a child of that ui, this should always exist
-            .unwrap();
+        #[expect(clippy::unwrap_used)] // Since we are a child of that ui, this should always exist
+        let menu_root_response = ui.ctx().read_response(menu_id).unwrap();
 
         let hover_pos = ui.ctx().pointer_hover_pos();
 

crates/egui/src/context.rs

@@ -584,8 +584,8 @@ impl ContextImpl {
         }
     }
 
-    fn accesskit_node_builder(&mut self, id: Id) -> &mut accesskit::Node {
-        let state = self.viewport().this_pass.accesskit_state.as_mut().unwrap();
+    fn accesskit_node_builder(&mut self, id: Id) -> Option<&mut accesskit::Node> {
+        let state = self.viewport().this_pass.accesskit_state.as_mut()?;
         let builders = &mut state.nodes;
 
         if let std::collections::hash_map::Entry::Vacant(entry) = builders.entry(id) {
@@ -611,11 +611,11 @@ impl ContextImpl {
             let parent_id = find_accesskit_parent(&state.parent_map, builders, id)
                 .unwrap_or_else(crate::accesskit_root_id);
 
-            let parent_builder = builders.get_mut(&parent_id).unwrap();
+            let parent_builder = builders.get_mut(&parent_id)?;
             parent_builder.push_child(id.accesskit_id());
         }
 
-        builders.get_mut(&id).unwrap()
+        builders.get_mut(&id)
     }
 
     fn pixels_per_point(&mut self) -> f32 {
@@ -3639,14 +3639,7 @@ impl Context {
         id: Id,
         writer: impl FnOnce(&mut accesskit::Node) -> R,
     ) -> Option<R> {
-        self.write(|ctx| {
-            ctx.viewport()
-                .this_pass
-                .accesskit_state
-                .is_some()
-                .then(|| ctx.accesskit_node_builder(id))
-                .map(writer)
-        })
+        self.write(|ctx| ctx.accesskit_node_builder(id).map(writer))
     }
 
     pub(crate) fn register_accesskit_parent(&self, id: Id, parent_id: Id) {

crates/egui/src/hit_test.rs

@@ -361,7 +361,10 @@ fn hit_test_on_close(close: &[WidgetRect], pos: Pos2) -> WidgetHits {
 
         (Some(hit_click), Some(hit_drag)) => {
             // We have a perfect hit on both click and drag. Which is the topmost?
+            #[expect(clippy::unwrap_used)]
             let click_idx = close.iter().position(|w| *w == hit_click).unwrap();
+
+            #[expect(clippy::unwrap_used)]
             let drag_idx = close.iter().position(|w| *w == hit_drag).unwrap();
 
             let click_is_on_top_of_drag = drag_idx < click_idx;

crates/egui/src/input_state/mod.rs

@@ -1551,11 +1551,9 @@ impl InputState {
             options: _,
         } = self;
 
-        ui.style_mut()
-            .text_styles
-            .get_mut(&crate::TextStyle::Body)
-            .unwrap()
-            .family = crate::FontFamily::Monospace;
+        if let Some(style) = ui.style_mut().text_styles.get_mut(&crate::TextStyle::Body) {
+            style.family = crate::FontFamily::Monospace;
+        }
 
         ui.collapsing("Raw Input", |ui| raw.ui(ui));
 

crates/egui/src/input_state/touch_state.rs

@@ -288,6 +288,7 @@ impl TouchState {
             // touch individually, and then calculate the average of all individual changes in
             // direction. But this approach cannot be implemented locally in this method, making
             // everything a bit more complicated.
+            #[expect(clippy::unwrap_used)] // guarded against already
             let first_touch = self.active_touches.values().next().unwrap();
             state.heading = (state.avg_pos - first_touch.pos).angle();
 
@@ -323,13 +324,14 @@ enum PinchType {
 
 impl PinchType {
     fn classify(touches: &BTreeMap<TouchId, ActiveTouch>) -> Self {
+        #![expect(clippy::unwrap_used)]
+
         // For non-proportional 2d zooming:
         // If the user is pinching with two fingers that have roughly the same Y coord,
         // then the Y zoom is unstable and should be 1.
         // Similarly, if the fingers are directly above/below each other,
         // we should only zoom on the Y axis.
         // If the fingers are roughly on a diagonal, we revert to the proportional zooming.
-
         if touches.len() == 2 {
             let mut touches = touches.values();
             let t0 = touches.next().unwrap().pos;

crates/egui/src/memory/mod.rs

@@ -306,6 +306,8 @@ impl Default for Options {
             zoom_with_keyboard: true,
             tessellation_options: Default::default(),
             repaint_on_widget_change: false,
+
+            #[expect(clippy::unwrap_used)]
             max_passes: NonZeroUsize::new(2).unwrap(),
             screen_reader: false,
             warn_on_id_clash: cfg!(debug_assertions),

crates/egui/src/util/id_type_map.rs

@@ -142,7 +142,9 @@ impl Element {
         Self::Value {
             value: Box::new(t),
             clone_fn: |x| {
-                let x = x.downcast_ref::<T>().unwrap(); // This unwrap will never panic, because we always construct this type using this `new` function and because we return &mut reference only with this type `T`, so type cannot change.
+                // This unwrap will never panic, because we always construct this type using this `new` function and because we return &mut reference only with this type `T`, so type cannot change.
+                #[expect(clippy::unwrap_used)]
+                let x = x.downcast_ref::<T>().unwrap();
                 Box::new(x.clone())
             },
             #[cfg(feature = "persistence")]
@@ -156,12 +158,16 @@ impl Element {
         Self::Value {
             value: Box::new(t),
             clone_fn: |x| {
-                let x = x.downcast_ref::<T>().unwrap(); // This unwrap will never panic, because we always construct this type using this `new` function and because we return &mut reference only with this type `T`, so type cannot change.
+                // This unwrap will never panic, because we always construct this type using this `new` function and because we return &mut reference only with this type `T`, so type cannot change.
+                #[expect(clippy::unwrap_used)]
+                let x = x.downcast_ref::<T>().unwrap();
                 Box::new(x.clone())
             },
             #[cfg(feature = "persistence")]
             serialize_fn: Some(|x| {
-                let x = x.downcast_ref::<T>().unwrap(); // This will never panic too, for same reason.
+                // This will never panic too, for same reason.
+                #[expect(clippy::unwrap_used)]
+                let x = x.downcast_ref::<T>().unwrap();
                 ron::to_string(x).ok()
             }),
         }
@@ -209,7 +215,9 @@ impl Element {
         }
 
         match self {
-            Self::Value { value, .. } => value.downcast_mut().unwrap(), // This unwrap will never panic because we already converted object to required type
+            // This unwrap will never panic because we already converted object to required type
+            #[expect(clippy::unwrap_used)]
+            Self::Value { value, .. } => value.downcast_mut().unwrap(),
             Self::Serialized(_) => unreachable!(),
         }
     }
@@ -238,7 +246,9 @@ impl Element {
         }
 
         match self {
-            Self::Value { value, .. } => value.downcast_mut().unwrap(), // This unwrap will never panic because we already converted object to required type
+            // This unwrap will never panic because we already converted object to required type
+            #[expect(clippy::unwrap_used)]
+            Self::Value { value, .. } => value.downcast_mut().unwrap(),
             Self::Serialized(_) => unreachable!(),
         }
     }
@@ -436,10 +446,14 @@ impl IdTypeMap {
         let hash = hash(TypeId::of::<T>(), id);
         use std::collections::hash_map::Entry;
         match self.map.entry(hash) {
-            Entry::Vacant(vacant) => vacant
+            Entry::Vacant(vacant) => {
+                // this unwrap will never panic, because we insert correct type right now
+                #[expect(clippy::unwrap_used)]
+                vacant
                     .insert(Element::new_temp(insert_with()))
                     .get_mut_temp()
-                .unwrap(), // this unwrap will never panic, because we insert correct type right now
+                    .unwrap()
+            }
             Entry::Occupied(occupied) => {
                 occupied.into_mut().get_temp_mut_or_insert_with(insert_with)
             }
@@ -454,10 +468,14 @@ impl IdTypeMap {
         let hash = hash(TypeId::of::<T>(), id);
         use std::collections::hash_map::Entry;
         match self.map.entry(hash) {
-            Entry::Vacant(vacant) => vacant
+            Entry::Vacant(vacant) => {
+                // this unwrap will never panic, because we insert correct type right now
+                #[expect(clippy::unwrap_used)]
+                vacant
                     .insert(Element::new_persisted(insert_with()))
                     .get_mut_persisted()
-                .unwrap(), // this unwrap will never panic, because we insert correct type right now
+                    .unwrap()
+            }
             Entry::Occupied(occupied) => occupied
                 .into_mut()
                 .get_persisted_mut_or_insert_with(insert_with),

crates/egui/src/util/undoer.rs

@@ -135,6 +135,7 @@ where
             self.flux = None;
 
             if self.undos.back() == Some(current_state) {
+                #[expect(clippy::unwrap_used)] // we just checked that undos is not empty
                 self.redos.push(self.undos.pop_back().unwrap());
             } else {
                 self.redos.push(current_state.clone());

crates/egui/src/widgets/text_edit/builder.rs

@@ -827,8 +827,7 @@ impl TextEdit<'_> {
                     hint_text_str.as_str(),
                 )
             });
-        } else if selection_changed {
-            let cursor_range = cursor_range.unwrap();
+        } else if selection_changed && let Some(cursor_range) = cursor_range {
             let char_range = cursor_range.primary.index..=cursor_range.secondary.index;
             let info = WidgetInfo::text_selection_changed(
                 ui.is_enabled(),

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,

crates/egui_demo_lib/src/lib.rs

@@ -8,8 +8,7 @@
 #![cfg_attr(feature = "document-features", doc = document_features::document_features!())]
 //!
 
-#![allow(clippy::float_cmp)]
-#![allow(clippy::manual_range_contains)]
+#![expect(clippy::unwrap_used)] // TODO(emilk): avoid unwraps
 
 mod demo;
 pub mod easy_mark;

crates/egui_extras/src/datepicker/mod.rs

@@ -1,3 +1,5 @@
+#![expect(clippy::unwrap_used)] // TODO(emilk): avoid unwraps
+
 mod button;
 mod popup;
 

crates/egui_glow/examples/pure_glow.rs

@@ -1,9 +1,9 @@
 //! Example how to use pure `egui_glow`.
 
 #![cfg_attr(not(debug_assertions), windows_subsystem = "windows")] // hide console window on Windows in release
-#![allow(rustdoc::missing_crate_level_docs)] // it's an example
-#![allow(clippy::undocumented_unsafe_blocks)]
-#![allow(unsafe_code)]
+#![expect(rustdoc::missing_crate_level_docs, clippy::unwrap_used)] // it's an example
+#![expect(clippy::undocumented_unsafe_blocks)]
+#![expect(unsafe_code)]
 
 use std::num::NonZeroU32;
 use std::sync::Arc;

crates/egui_glow/src/painter.rs

@@ -1,4 +1,5 @@
 #![allow(clippy::collapsible_else_if)]
+#![allow(clippy::unwrap_used)]
 #![allow(unsafe_code)]
 
 use std::{collections::HashMap, sync::Arc};

crates/egui_glow/src/shader_version.rs

@@ -1,5 +1,6 @@
-#![allow(unsafe_code)]
-#![allow(clippy::undocumented_unsafe_blocks)]
+#![expect(clippy::undocumented_unsafe_blocks)]
+#![expect(clippy::unwrap_used)] // TODO(emilk): avoid unwraps
+#![expect(unsafe_code)]
 
 use std::convert::TryInto as _;
 

crates/egui_glow/src/vao.rs

@@ -1,4 +1,5 @@
-#![allow(unsafe_code)]
+#![expect(unsafe_code)]
+#![expect(clippy::unwrap_used)]
 
 use glow::HasContext as _;
 

crates/egui_glow/src/winit.rs

@@ -28,6 +28,7 @@ impl EguiGlow {
         native_pixels_per_point: Option<f32>,
         dithering: bool,
     ) -> Self {
+        #[expect(clippy::unwrap_used)] // TODO(emilk): return error instead of unwrap
         let painter = crate::Painter::new(gl, "", shader_version, dithering)
             .map_err(|err| {
                 log::error!("error occurred in initializing painter:\n{err}");

crates/egui_kittest/src/lib.rs

@@ -2,6 +2,7 @@
 //!
 //! ## Feature flags
 #![cfg_attr(feature = "document-features", doc = document_features::document_features!())]
+#![expect(clippy::unwrap_used)] // TODO(emilk): avoid unwraps
 
 mod builder;
 #[cfg(feature = "snapshot")]

crates/emath/src/lib.rs

@@ -233,7 +233,9 @@ pub fn format_with_decimals_in_range(value: f64, decimal_range: RangeInclusive<u
         for decimals in min_decimals..max_decimals {
             let text = format!("{value:.decimals$}");
             let epsilon = 16.0 * f32::EPSILON; // margin large enough to handle most peoples round-tripping needs
-            if almost_equal(text.parse::<f32>().unwrap(), value as f32, epsilon) {
+            if let Ok(parsed_value) = text.parse::<f32>()
+                && almost_equal(parsed_value, value as f32, epsilon)
+            {
                 // Enough precision to show the value accurately - good!
                 return text;
             }

crates/epaint/src/mesh.rs

@@ -281,7 +281,12 @@ impl Mesh {
             let mesh = Mesh16 {
                 indices: self.indices[span_start..index_cursor]
                     .iter()
-                    .map(|vi| u16::try_from(vi - min_vindex).unwrap())
+                    .map(|vi| {
+                        #[expect(clippy::unwrap_used)]
+                        {
+                            u16::try_from(vi - min_vindex).unwrap()
+                        }
+                    })
                     .collect(),
                 vertices: self.vertices[(min_vindex as usize)..=(max_vindex as usize)].to_vec(),
                 texture_id: self.texture_id,

crates/epaint/src/tessellator.rs

@@ -1403,6 +1403,7 @@ impl Tessellator {
             });
         }
 
+        #[expect(clippy::unwrap_used)] // it's never empty
         let out = out_primitives.last_mut().unwrap();
 
         if let Primitive::Mesh(out_mesh) = &mut out.primitive {

crates/epaint/src/text/text_layout.rs

@@ -1,3 +1,5 @@
+#![expect(clippy::unwrap_used)] // TODO(emilk): remove unwraps
+
 use std::sync::Arc;
 
 use emath::{Align, GuiRounding as _, NumExt as _, Pos2, Rect, Vec2, pos2, vec2};

examples/external_eventloop/src/main.rs

@@ -1,5 +1,5 @@
 #![cfg_attr(not(debug_assertions), windows_subsystem = "windows")] // hide console window on Windows in release
-#![allow(rustdoc::missing_crate_level_docs)] // it's an example
+#![expect(rustdoc::missing_crate_level_docs, clippy::unwrap_used)] // it's an example
 
 use eframe::{UserEvent, egui};
 use std::{cell::Cell, rc::Rc};

examples/external_eventloop_async/src/app.rs

@@ -1,3 +1,5 @@
+#![expect(clippy::unwrap_used)] // It's an example
+
 use std::{cell::Cell, io, os::fd::AsRawFd as _, rc::Rc, time::Duration};
 
 use tokio::task::LocalSet;

examples/hello_world_par/src/main.rs

@@ -1,7 +1,7 @@
 //! This example shows that you can use egui in parallel from multiple threads.
 
 #![cfg_attr(not(debug_assertions), windows_subsystem = "windows")] // hide console window on Windows in release
-#![allow(rustdoc::missing_crate_level_docs)] // it's an example
+#![expect(clippy::unwrap_used)] // it's an example
 
 use std::sync::mpsc;
 use std::thread::JoinHandle;

examples/screenshot/src/main.rs

@@ -1,5 +1,5 @@
 #![cfg_attr(not(debug_assertions), windows_subsystem = "windows")] // hide console window on Windows in release
-#![allow(rustdoc::missing_crate_level_docs)] // it's an example
+#![expect(rustdoc::missing_crate_level_docs, clippy::unwrap_used)] // it's an example
 
 use std::sync::Arc;
 

tests/egui_tests/tests/test_widgets.rs

@@ -1,3 +1,5 @@
+#![expect(clippy::unwrap_used)] // it's a test
+
 use egui::accesskit::Role;
 use egui::load::SizedTexture;
 use egui::{

tests/test_inline_glow_paint/src/main.rs

@@ -1,6 +1,10 @@
 #![cfg_attr(not(debug_assertions), windows_subsystem = "windows")] // hide console window on Windows in release
-#![allow(rustdoc::missing_crate_level_docs)] // it's an example
-#![allow(clippy::undocumented_unsafe_blocks)]
+#![expect(
+    // it's a test:
+    clippy::undocumented_unsafe_blocks,
+    clippy::unwrap_used,
+    rustdoc::missing_crate_level_docs
+)]
 
 // Test that we can paint to the screen using glow directly.
 

tests/test_viewports/src/main.rs

@@ -1,5 +1,5 @@
 #![cfg_attr(not(debug_assertions), windows_subsystem = "windows")] // hide console window on Windows in release
-#![allow(rustdoc::missing_crate_level_docs)] // it's an example
+#![expect(clippy::unwrap_used, rustdoc::missing_crate_level_docs)] // it's a test
 
 use std::sync::Arc;
 

xtask/src/utils.rs

@@ -1,3 +1,5 @@
+#![expect(clippy::unwrap_used)]
+
 use std::{
     env,
     io::{self, Write as _},