Improve clippy, and add more docs (#3306)

* Silence a few clippy warnings

* Use named threads

* Remove some deprecated functions

* Document Context and Ui fully

* Use `parking_lot::Mutex` in `eframe`

* Expand clippy.toml files

* build fix

crates/egui/src/context.rs

@@ -1,4 +1,5 @@
-// #![warn(missing_docs)]
+#![warn(missing_docs)] // Let's keep `Context` well-documented.
+
 use std::sync::Arc;
 
 use crate::{
@@ -1552,6 +1553,7 @@ impl Context {
 }
 
 impl Context {
+    /// Show a ui for settings (style and tessellation options).
     pub fn settings_ui(&self, ui: &mut Ui) {
         use crate::containers::*;
 
@@ -1574,6 +1576,7 @@ impl Context {
             });
     }
 
+    /// Show the state of egui, including its input and output.
     pub fn inspection_ui(&self, ui: &mut Ui) {
         use crate::containers::*;
         crate::trace!(ui);
@@ -1703,6 +1706,7 @@ impl Context {
         });
     }
 
+    /// Shows the contents of [`Self::memory`].
     pub fn memory_ui(&self, ui: &mut crate::Ui) {
         if ui
             .button("Reset all")
@@ -1803,6 +1807,7 @@ impl Context {
 }
 
 impl Context {
+    /// Edit the active [`Style`].
     pub fn style_ui(&self, ui: &mut Ui) {
         let mut style: Style = (*self.style()).clone();
         style.ui(ui);
@@ -1818,6 +1823,8 @@ impl Context {
     /// the function is still called, but with no other effect.
     ///
     /// No locks are held while the given closure is called.
+    #[allow(clippy::unused_self)]
+    #[inline]
     pub fn with_accessibility_parent(&self, _id: Id, f: impl FnOnce()) {
         // TODO(emilk): this isn't thread-safe - another thread can call this function between the push/pop calls
         #[cfg(feature = "accesskit")]

crates/egui/src/os.rs

@@ -1,3 +1,5 @@
+/// An `enum` of common operating systems.
+#[allow(clippy::upper_case_acronyms)] // `Ios` looks too ugly
 #[derive(Clone, Copy, Debug, PartialEq, Eq, Hash)]
 pub enum OperatingSystem {
     /// Unknown OS - could be wasm
@@ -26,6 +28,7 @@ impl Default for OperatingSystem {
 }
 
 impl OperatingSystem {
+    /// Uses the compile-time `target_arch` to identify the OS.
     pub const fn from_target_os() -> Self {
         if cfg!(target_arch = "wasm32") {
             Self::Unknown

crates/egui/src/ui.rs

@@ -1,4 +1,4 @@
-// #![warn(missing_docs)]
+#![warn(missing_docs)] // Let's keep `Ui` well-documented.
 
 use std::hash::Hash;
 use std::sync::Arc;
@@ -249,11 +249,6 @@ impl Ui {
         self.painter.is_visible()
     }
 
-    #[deprecated = "Renamed is_visible"]
-    pub fn visible(&self) -> bool {
-        self.painter.is_visible()
-    }
-
     /// Calling `set_visible(false)` will cause all further widgets to be invisible,
     /// yet still allocate space.
     ///
@@ -281,6 +276,7 @@ impl Ui {
         }
     }
 
+    /// Read the [`Layout`].
     #[inline]
     pub fn layout(&self) -> &Layout {
         self.placer.layout()
@@ -611,6 +607,7 @@ impl Ui {
         Id::new(self.next_auto_id_source)
     }
 
+    /// Same as `ui.next_auto_id().with(id_source)`
     pub fn auto_id_with<IdSource>(&self, id_source: IdSource) -> Id
     where
         IdSource: Hash,
@@ -618,6 +615,7 @@ impl Ui {
         Id::new(self.next_auto_id_source).with(id_source)
     }
 
+    /// Pretend like `count` widgets have been allocated.
     pub fn skip_ahead_auto_ids(&mut self, count: usize) {
         self.next_auto_id_source = self.next_auto_id_source.wrapping_add(count as u64);
     }
@@ -2038,11 +2036,6 @@ impl Ui {
         InnerResponse::new(inner, self.interact(rect, child_ui.id, Sense::hover()))
     }
 
-    #[deprecated = "Use ui.vertical_centered or ui.centered_and_justified"]
-    pub fn centered<R>(&mut self, add_contents: impl FnOnce(&mut Self) -> R) -> InnerResponse<R> {
-        self.vertical_centered(add_contents)
-    }
-
     /// This will make the next added widget centered and justified in the available space.
     ///
     /// Only one widget may be added to the inner `Ui`!