fix clippy issues

crates/ui/src/accordion.rs

@@ -8,6 +8,8 @@ use gpui::{
 
 use crate::{h_flex, theme::ActiveTheme as _, v_flex, Icon, IconName, Sizable, Size};
 
+type OnToggleClick = Option<Arc<dyn Fn(&[usize], &mut WindowContext) + Send + Sync>>;
+
 /// An AccordionGroup is a container for multiple Accordion elements.
 #[derive(IntoElement)]
 pub struct Accordion {
@@ -18,7 +20,7 @@ pub struct Accordion {
     bordered: bool,
     disabled: bool,
     children: Vec<AccordionItem>,
-    on_toggle_click: Option<Arc<dyn Fn(&[usize], &mut WindowContext) + Send + Sync>>,
+    on_toggle_click: OnToggleClick,
 }
 
 impl Accordion {
@@ -138,6 +140,8 @@ impl RenderOnce for Accordion {
     }
 }
 
+type OnToggle = Option<Arc<dyn Fn(&bool, &mut WindowContext)>>;
+
 /// An Accordion is a vertically stacked list of items, each of which can be expanded to reveal the content associated with it.
 #[derive(IntoElement)]
 pub struct AccordionItem {
@@ -148,7 +152,7 @@ pub struct AccordionItem {
     size: Size,
     bordered: bool,
     disabled: bool,
-    on_toggle_click: Option<Arc<dyn Fn(&bool, &mut WindowContext)>>,
+    on_toggle_click: OnToggle,
 }
 
 impl AccordionItem {
@@ -204,6 +208,12 @@ impl AccordionItem {
     }
 }
 
+impl Default for AccordionItem {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
 impl Sizable for AccordionItem {
     fn with_size(mut self, size: impl Into<Size>) -> Self {
         self.size = size.into();

crates/ui/src/animation.rs

@@ -12,8 +12,7 @@ pub fn cubic_bezier(x1: f32, y1: f32, x2: f32, y2: f32) -> impl Fn(f32) -> f32 {
 
         // The Bezier curve function for x and y, where x0 = 0, y0 = 0, x3 = 1, y3 = 1
         let _x = 3.0 * x1 * one_t2 * t + 3.0 * x2 * one_t * t2 + t3;
-        let y = 3.0 * y1 * one_t2 * t + 3.0 * y2 * one_t * t2 + t3;
 
-        y
+        3.0 * y1 * one_t2 * t + 3.0 * y2 * one_t * t2 + t3
     }
 }

crates/ui/src/breadcrumb.rs

@@ -12,11 +12,13 @@ pub struct Breadcrumb {
     items: Vec<BreadcrumbItem>,
 }
 
+type OnClick = Option<Rc<dyn Fn(&ClickEvent, &mut WindowContext)>>;
+
 #[derive(IntoElement)]
 pub struct BreadcrumbItem {
     id: ElementId,
     text: SharedString,
-    on_click: Option<Rc<dyn Fn(&ClickEvent, &mut WindowContext)>>,
+    on_click: OnClick,
     disabled: bool,
     is_last: bool,
 }
@@ -46,6 +48,7 @@ impl BreadcrumbItem {
     }
 
     /// For internal use only.
+    #[allow(clippy::wrong_self_convention)]
     fn is_last(mut self, is_last: bool) -> Self {
         self.is_last = is_last;
         self
@@ -84,6 +87,12 @@ impl Breadcrumb {
     }
 }
 
+impl Default for Breadcrumb {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
 #[derive(IntoElement)]
 struct BreadcrumbSeparator;
 impl RenderOnce for BreadcrumbSeparator {

crates/ui/src/button.rs

@@ -150,6 +150,8 @@ impl ButtonVariant {
     }
 }
 
+type OnClick = Option<Box<dyn Fn(&ClickEvent, &mut WindowContext) + 'static>>;
+
 /// A Button element.
 #[derive(IntoElement)]
 pub struct Button {
@@ -167,7 +169,7 @@ pub struct Button {
     size: Size,
     compact: bool,
     tooltip: Option<SharedString>,
-    on_click: Option<Box<dyn Fn(&ClickEvent, &mut WindowContext) + 'static>>,
+    on_click: OnClick,
     pub(crate) stop_propagation: bool,
     loading: bool,
     loading_icon: Option<Icon>,
@@ -509,10 +511,7 @@ impl ButtonVariant {
     }
 
     fn underline(&self, _: &WindowContext) -> bool {
-        match self {
+        matches!(self, ButtonVariant::Link)
-            ButtonVariant::Link => true,
-            _ => false,
-        }
     }
 
     fn shadow(&self, _: &WindowContext) -> bool {
@@ -576,7 +575,11 @@ impl ButtonVariant {
         let bg = match self {
             ButtonVariant::Primary => cx.theme().primary_active,
             ButtonVariant::Secondary | ButtonVariant::Outline | ButtonVariant::Ghost => {
-                cx.theme().secondary_active
+                if cx.theme().mode.is_dark() {
+                    cx.theme().secondary.lighten(0.2).opacity(0.8)
+                } else {
+                    cx.theme().secondary.darken(0.2).opacity(0.8)
+                }
             }
             ButtonVariant::Danger => cx.theme().destructive_active,
             ButtonVariant::Link => cx.theme().transparent,
@@ -605,7 +608,11 @@ impl ButtonVariant {
         let bg = match self {
             ButtonVariant::Primary => cx.theme().primary_active,
             ButtonVariant::Secondary | ButtonVariant::Outline | ButtonVariant::Ghost => {
-                cx.theme().secondary_active
+                if cx.theme().mode.is_dark() {
+                    cx.theme().secondary.lighten(0.2).opacity(0.8)
+                } else {
+                    cx.theme().secondary.darken(0.2).opacity(0.8)
+                }
             }
             ButtonVariant::Danger => cx.theme().destructive_active,
             ButtonVariant::Link => cx.theme().transparent,

crates/ui/src/button_group.rs

@@ -9,6 +9,8 @@ use crate::{
     Disableable, Sizable, Size,
 };
 
+type OnClick = Option<Box<dyn Fn(&Vec<usize>, &mut WindowContext) + 'static>>;
+
 /// A ButtonGroup element, to wrap multiple buttons in a group.
 #[derive(IntoElement)]
 pub struct ButtonGroup {
@@ -23,7 +25,7 @@ pub struct ButtonGroup {
     variant: Option<ButtonVariant>,
     size: Option<Size>,
 
-    on_click: Option<Box<dyn Fn(&Vec<usize>, &mut WindowContext) + 'static>>,
+    on_click: OnClick,
 }
 
 impl Disableable for ButtonGroup {
@@ -118,7 +120,8 @@ impl RenderOnce for ButtonGroup {
                     .enumerate()
                     .map(|(child_index, child)| {
                         let state = Rc::clone(&state);
-                        let child = if children_len == 1 {
+
+                        if children_len == 1 {
                             child
                         } else if child_index == 0 {
                             // First
@@ -167,9 +170,7 @@ impl RenderOnce for ButtonGroup {
                         .when_some(self.compact, |this, _| this.compact())
                         .on_click(move |_, _| {
                             state.set(Some(child_index));
-                        });
+                        })
-
-                        child
                     }),
             )
             .when_some(

crates/ui/src/checkbox.rs

@@ -5,6 +5,8 @@ use gpui::{
     WindowContext,
 };
 
+type OnClick = Option<Box<dyn Fn(&bool, &mut WindowContext) + 'static>>;
+
 /// A Checkbox element.
 #[derive(IntoElement)]
 pub struct Checkbox {
@@ -12,7 +14,7 @@ pub struct Checkbox {
     label: Option<SharedString>,
     checked: bool,
     disabled: bool,
-    on_click: Option<Box<dyn Fn(&bool, &mut WindowContext) + 'static>>,
+    on_click: OnClick,
 }
 
 impl Checkbox {

crates/ui/src/clipboard.rs

@@ -10,11 +10,14 @@ use crate::{
     h_flex, IconName, Sizable as _,
 };
 
+type ContentBuilder = Option<Box<dyn Fn(&mut WindowContext) -> AnyElement>>;
+type CopiedCallback = Option<Rc<dyn Fn(SharedString, &mut WindowContext)>>;
+
 pub struct Clipboard {
     id: ElementId,
     value: SharedString,
-    content_builder: Option<Box<dyn Fn(&mut WindowContext) -> AnyElement>>,
+    content_builder: ContentBuilder,
-    copied_callback: Option<Rc<dyn Fn(SharedString, &mut WindowContext)>>,
+    copied_callback: CopiedCallback,
 }
 
 impl Clipboard {

crates/ui/src/context_menu.rs

@@ -21,10 +21,12 @@ pub trait ContextMenuExt: ParentElement + Sized {
 impl<E> ContextMenuExt for Stateful<E> where E: ParentElement {}
 impl<E> ContextMenuExt for Focusable<E> where E: ParentElement {}
 
+type Menu<M> = Option<Box<dyn Fn(PopupMenu, &mut ViewContext<M>) -> PopupMenu + 'static>>;
+
 /// A context menu that can be shown on right-click.
 pub struct ContextMenu {
     id: ElementId,
-    menu: Option<Box<dyn Fn(PopupMenu, &mut ViewContext<PopupMenu>) -> PopupMenu + 'static>>,
+    menu: Menu<PopupMenu>,
     anchor: AnchorCorner,
 }
 
@@ -99,13 +101,17 @@ impl Element for ContextMenu {
         id: Option<&gpui::GlobalElementId>,
         cx: &mut WindowContext,
     ) -> (gpui::LayoutId, Self::RequestLayoutState) {
-        let mut style = Style::default();
         // Set the layout style relative to the table view to get same size.
-        style.position = Position::Absolute;
+        let style = Style {
-        style.flex_grow = 1.0;
+            position: Position::Absolute,
-        style.flex_shrink = 1.0;
+            flex_grow: 1.0,
-        style.size.width = relative(1.).into();
+            flex_shrink: 1.0,
-        style.size.height = relative(1.).into();
+            size: gpui::Size {
+                width: relative(1.).into(),
+                height: relative(1.).into(),
+            },
+            ..Default::default()
+        };
 
         let anchor = self.anchor;
 

crates/ui/src/dock/mod.rs

@@ -1,3 +1,4 @@
+#[allow(clippy::module_inception)]
 mod dock;
 mod invalid_panel;
 mod panel;
@@ -6,7 +7,7 @@ mod state;
 mod tab_panel;
 
 use anyhow::Result;
-pub use dock::*;
+
 use gpui::{
     actions, canvas, div, prelude::FluentBuilder, AnyElement, AnyView, AppContext, Axis, Bounds,
     Edges, Entity as _, EntityId, EventEmitter, InteractiveElement as _, IntoElement,
@@ -15,11 +16,14 @@ use gpui::{
 };
 use std::sync::Arc;
 
+pub use dock::*;
 pub use panel::*;
 pub use stack_panel::*;
 pub use state::*;
 pub use tab_panel::*;
 
+use crate::theme::ActiveTheme;
+
 pub fn init(cx: &mut AppContext) {
     cx.set_global(PanelRegistry::new());
 }
@@ -232,7 +236,7 @@ impl DockItem {
             }
             Self::Split { view, items, .. } => {
                 // Iter items to add panel to the first tabs
-                for item in items.into_iter() {
+                for item in items.iter_mut() {
                     if let DockItem::Tabs { view, .. } = item {
                         view.update(cx, |tab_panel, cx| {
                             tab_panel.add_panel(panel.clone(), cx);
@@ -636,12 +640,12 @@ impl DockArea {
                 }
 
                 self._subscriptions
-                    .push(cx.subscribe(view, move |_, _, event, cx| match event {
+                    .push(cx.subscribe(view, move |_, _, event, cx| {
-                        PanelEvent::LayoutChanged => {
+                        if let PanelEvent::LayoutChanged = event {
                             let dock_area = cx.view().clone();
                             cx.spawn(|_, mut cx| async move {
                                 let _ = cx.update(|cx| {
-                                    let _ = dock_area.update(cx, |view, cx| {
+                                    dock_area.update(cx, |view, cx| {
                                         view.update_toggle_button_tab_panels(cx)
                                     });
                                 });
@@ -649,7 +653,6 @@ impl DockArea {
                             .detach();
                             cx.emit(DockEvent::LayoutChanged);
                         }
-                        _ => {}
                     }));
             }
             DockItem::Tabs { .. } => {
@@ -673,7 +676,7 @@ impl DockArea {
                 let panel = panel.clone();
                 cx.spawn(|_, mut cx| async move {
                     let _ = cx.update(|cx| {
-                        let _ = dock_area.update(cx, |dock, cx| {
+                        dock_area.update(cx, |dock, cx| {
                             dock.set_zoomed_in(panel, cx);
                             cx.notify();
                         });
@@ -685,7 +688,7 @@ impl DockArea {
                 let dock_area = cx.view().clone();
                 cx.spawn(|_, mut cx| async move {
                     let _ = cx.update(|cx| {
-                        let _ = dock_area.update(cx, |view, cx| view.set_zoomed_out(cx));
+                        dock_area.update(cx, |view, cx| view.set_zoomed_out(cx));
                     });
                 })
                 .detach()
@@ -694,8 +697,7 @@ impl DockArea {
                 let dock_area = cx.view().clone();
                 cx.spawn(|_, mut cx| async move {
                     let _ = cx.update(|cx| {
-                        let _ = dock_area
+                        dock_area.update(cx, |view, cx| view.update_toggle_button_tab_panels(cx));
-                            .update(cx, |view, cx| view.update_toggle_button_tab_panels(cx));
                     });
                 })
                 .detach();
@@ -780,6 +782,8 @@ impl Render for DockArea {
                             // Left dock
                             .when_some(self.left_dock.clone(), |this, dock| {
                                 this.child(div().flex().flex_none().child(dock))
+                                    .bg(cx.theme().sidebar)
+                                    .text_color(cx.theme().sidebar_foreground)
                             })
                             // Center
                             .child(

crates/ui/src/dock/panel.rs

@@ -143,8 +143,7 @@ impl PartialEq for dyn PanelView {
     }
 }
 
-pub struct PanelRegistry {
+type PanelRegistryItem = HashMap<
-    pub(super) items: HashMap<
     String,
     Arc<
         dyn Fn(
@@ -154,8 +153,12 @@ pub struct PanelRegistry {
             &mut WindowContext,
         ) -> Box<dyn PanelView>,
     >,
-    >,
+>;
+
+pub struct PanelRegistry {
+    pub(super) items: PanelRegistryItem,
 }
+
 impl PanelRegistry {
     pub fn new() -> Self {
         Self {
@@ -163,6 +166,13 @@ impl PanelRegistry {
         }
     }
 }
+
+impl Default for PanelRegistry {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
 impl Global for PanelRegistry {}
 
 /// Register the Panel init by panel_name to global registry.
@@ -176,7 +186,7 @@ where
         ) -> Box<dyn PanelView>
         + 'static,
 {
-    if let None = cx.try_global::<PanelRegistry>() {
+    if cx.try_global::<PanelRegistry>().is_none() {
         cx.set_global(PanelRegistry::new());
     }
 

crates/ui/src/dock/stack_panel.rs

@@ -184,7 +184,7 @@ impl StackPanel {
         cx: &mut ViewContext<Self>,
     ) {
         // If the panel is already in the stack, return.
-        if let Some(_) = self.index_of_panel(panel.clone()) {
+        if self.index_of_panel(panel.clone()).is_some() {
             return;
         }
 

crates/ui/src/dock/tab_panel.rs

@@ -456,7 +456,7 @@ impl TabPanel {
         let right_dock_button = self.render_dock_toggle_button(DockPlacement::Right, cx);
 
         if self.panels.len() == 1 && panel_style == PanelStyle::Default {
-            let panel = self.panels.get(0).unwrap();
+            let panel = self.panels.first().unwrap();
             let title_style = panel.title_style(cx);
 
             return h_flex()
@@ -694,6 +694,7 @@ impl TabPanel {
 
         // If target is same tab, and it is only one panel, do nothing.
         if is_same_tab && ix.is_none() {
+            #[allow(clippy::if_same_then_else)]
             if self.will_split_placement.is_none() {
                 return;
             } else if self.panels.len() == 1 {
@@ -708,7 +709,7 @@ impl TabPanel {
         if is_same_tab {
             self.detach_panel(panel.clone(), cx);
         } else {
-            let _ = drag.tab_panel.update(cx, |view, cx| {
+            drag.tab_panel.update(cx, |view, cx| {
                 view.detach_panel(panel.clone(), cx);
                 view.remove_self_if_empty(cx);
             });

crates/ui/src/drawer.rs

@@ -21,17 +21,20 @@ use crate::{
 actions!(drawer, [Escape]);
 
 const CONTEXT: &str = "Drawer";
+
 pub fn init(cx: &mut AppContext) {
     cx.bind_keys([KeyBinding::new("escape", Escape, Some(CONTEXT))])
 }
 
+type OnClose = Rc<dyn Fn(&ClickEvent, &mut WindowContext) + 'static>;
+
 #[derive(IntoElement)]
 pub struct Drawer {
     pub(crate) focus_handle: FocusHandle,
     placement: Placement,
     size: DefiniteLength,
     resizable: bool,
-    on_close: Rc<dyn Fn(&ClickEvent, &mut WindowContext) + 'static>,
+    on_close: OnClose,
     title: Option<AnyElement>,
     footer: Option<AnyElement>,
     content: Div,

crates/ui/src/dropdown.rs

@@ -41,7 +41,7 @@ impl DropdownItem for String {
     }
 
     fn value(&self) -> &Self::Value {
-        &self
+        self
     }
 }
 
@@ -53,7 +53,7 @@ impl DropdownItem for SharedString {
     }
 
     fn value(&self) -> &Self::Value {
-        &self
+        self
     }
 }
 
@@ -211,6 +211,8 @@ pub enum DropdownEvent<D: DropdownDelegate + 'static> {
     Confirm(Option<<D::Item as DropdownItem>::Value>),
 }
 
+type Empty = Option<Box<dyn Fn(&WindowContext) -> AnyElement + 'static>>;
+
 /// A Dropdown element.
 pub struct Dropdown<D: DropdownDelegate + 'static> {
     id: ElementId,
@@ -223,7 +225,7 @@ pub struct Dropdown<D: DropdownDelegate + 'static> {
     placeholder: Option<SharedString>,
     title_prefix: Option<SharedString>,
     selected_value: Option<<D::Item as DropdownItem>::Value>,
-    empty: Option<Box<dyn Fn(&WindowContext) -> AnyElement + 'static>>,
+    empty: Empty,
     width: Length,
     menu_width: Length,
     /// Store the bounds of the input

crates/ui/src/focusable.rs

@@ -30,8 +30,7 @@ pub trait FocusableCycle {
         let target_focus_handle = handles
             .into_iter()
             .skip_while(|handle| Some(handle) != focused_handle.as_ref())
-            .skip(1)
+            .nth(1)
-            .next()
             .unwrap_or(fallback_handle);
 
         target_focus_handle.focus(cx);

crates/ui/src/history.rs

@@ -124,6 +124,15 @@ where
     }
 }
 
+impl<I> Default for History<I>
+where
+    I: HistoryItem,
+{
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
@@ -192,6 +201,6 @@ mod tests {
         let changes = history.undo().unwrap();
         assert_eq!(changes[0].tab_index, 0);
 
-        assert_eq!(history.undo().is_none(), true);
+        assert!(history.undo().is_none());
     }
 }

crates/ui/src/indicator.rs

@@ -35,6 +35,12 @@ impl Indicator {
     }
 }
 
+impl Default for Indicator {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
 impl Sizable for Indicator {
     fn with_size(mut self, size: impl Into<Size>) -> Self {
         self.size = size.into();

crates/ui/src/input/clear_button.rs

@@ -9,6 +9,7 @@ use crate::{
 pub(crate) struct ClearButton {}
 
 impl ClearButton {
+    #[allow(clippy::new_ret_no_self)]
     pub fn new(cx: &mut WindowContext) -> Button {
         Button::new("clean")
             .icon(Icon::new(IconName::CircleX).text_color(cx.theme().muted_foreground))

crates/ui/src/input/element.rs

@@ -134,7 +134,7 @@ impl TextElement {
                 }
             }
 
-            bounds.origin = bounds.origin + scroll_offset;
+            bounds.origin += scroll_offset;
 
             if input.show_cursor(cx) {
                 // cursor blink
@@ -268,7 +268,7 @@ impl TextElement {
 
         // print_points_as_svg_path(&line_corners, &points);
 
-        let first_p = *points.get(0).unwrap();
+        let first_p = *points.first().unwrap();
         let mut path = gpui::Path::new(bounds.origin + first_p);
         for p in points.iter().skip(1) {
             path.line_to(bounds.origin + *p);
@@ -295,10 +295,7 @@ impl IntoElement for TextElement {
 
 /// A debug function to print points as SVG path.
 #[allow(unused)]
-fn print_points_as_svg_path(
+fn print_points_as_svg_path(line_corners: &Vec<Corners<Point<Pixels>>>, points: &[Point<Pixels>]) {
-    line_corners: &Vec<Corners<Point<Pixels>>>,
-    points: &Vec<Point<Pixels>>,
-) {
     for corners in line_corners {
         println!(
             "tl: ({}, {}), tr: ({}, {}), bl: ({}, {}), br: ({}, {})",
@@ -313,7 +310,7 @@ fn print_points_as_svg_path(
         );
     }
 
-    if points.len() > 0 {
+    if !points.is_empty() {
         println!("M{},{}", points[0].x.0 as i32, points[0].y.0 as i32);
         for p in points.iter().skip(1) {
             println!("L{},{}", p.x.0 as i32, p.y.0 as i32);

crates/ui/src/input/input.rs

@@ -145,14 +145,17 @@ pub fn init(cx: &mut AppContext) {
     ]);
 }
 
+type Affixes<T> = Option<Box<dyn Fn(&mut ViewContext<T>) -> AnyElement + 'static>>;
+type Validate = Option<Box<dyn Fn(&str) -> bool + 'static>>;
+
 pub struct TextInput {
     pub(super) focus_handle: FocusHandle,
     pub(super) text: SharedString,
     multi_line: bool,
     pub(super) history: History<Change>,
     pub(super) blink_cursor: Model<BlinkCursor>,
-    pub(super) prefix: Option<Box<dyn Fn(&mut ViewContext<Self>) -> AnyElement + 'static>>,
+    pub(super) prefix: Affixes<Self>,
-    pub(super) suffix: Option<Box<dyn Fn(&mut ViewContext<Self>) -> AnyElement + 'static>>,
+    pub(super) suffix: Affixes<Self>,
     pub(super) loading: bool,
     pub(super) placeholder: SharedString,
     pub(super) selected_range: Range<usize>,
@@ -177,7 +180,7 @@ pub struct TextInput {
     pub(super) size: Size,
     pub(super) rows: usize,
     pattern: Option<regex::Regex>,
-    validate: Option<Box<dyn Fn(&str) -> bool + 'static>>,
+    validate: Validate,
     pub(crate) scroll_handle: ScrollHandle,
     scrollbar_state: Rc<Cell<ScrollbarState>>,
     /// The size of the scrollable content.
@@ -506,13 +509,12 @@ impl TextInput {
         }
 
         let offset = self.previous_boundary(self.cursor_offset());
-        let line = self
+
-            .text_for_range(self.range_to_utf16(&(0..offset + 1)), &mut None, cx)
+        self.text_for_range(self.range_to_utf16(&(0..offset + 1)), &mut None, cx)
             .unwrap_or_default()
             .rfind('\n')
             .map(|i| i + 1)
-            .unwrap_or(0);
+            .unwrap_or(0)
-        line
     }
 
     /// Get end of line
@@ -531,8 +533,7 @@ impl TextInput {
             return offset;
         }
 
-        let line = self
+        self.text_for_range(
-            .text_for_range(
             self.range_to_utf16(&(offset..self.text.len())),
             &mut None,
             cx,
@@ -540,8 +541,7 @@ impl TextInput {
         .unwrap_or_default()
         .find('\n')
         .map(|i| i + offset)
-            .unwrap_or(self.text.len());
+        .unwrap_or(self.text.len())
-        line
     }
 
     fn backspace(&mut self, _: &Backspace, cx: &mut ViewContext<Self>) {
@@ -675,7 +675,7 @@ impl TextInput {
         }
 
         let old_text = self
-            .text_for_range(self.range_to_utf16(&range), &mut None, cx)
+            .text_for_range(self.range_to_utf16(range), &mut None, cx)
             .unwrap_or("".to_string());
 
         let new_range = range.start..range.start + new_text.len();
@@ -753,7 +753,7 @@ impl TextInput {
         let mut y_offset = px(0.);
 
         for line in lines.iter() {
-            let line_origin = self.line_origin_with_y_offset(&mut y_offset, &line, line_height);
+            let line_origin = self.line_origin_with_y_offset(&mut y_offset, line, line_height);
             let mut pos = inner_position - line_origin;
             // Ignore the y position in single line mode, only check x position.
             if self.is_single_line() {
@@ -765,7 +765,10 @@ impl TextInput {
                 // Add 1 for place cursor after the character.
                 index += v + 1;
                 break;
-            } else if let Ok(_) = line.index_for_position(point(px(0.), pos.y), line_height) {
+            } else if line
+                .index_for_position(point(px(0.), pos.y), line_height)
+                .is_ok()
+            {
                 // Click in the this line but not in the text, move cursor to the end of the line.
                 // The fallback index is saved in Err from `index_for_position` method.
                 index += index_result.unwrap_err();
@@ -809,7 +812,7 @@ impl TextInput {
         if self.is_multi_line() {
             let p = point(px(0.), *y_offset);
             let height = line_height + line.wrap_boundaries.len() as f32 * line_height;
-            *y_offset = *y_offset + height;
+            *y_offset += height;
             p
         } else {
             point(px(0.), px(0.))
@@ -859,7 +862,7 @@ impl TextInput {
         let prev_chars = prev_text.chars().rev().peekable();
         let next_chars = next_text.chars().peekable();
 
-        for (_, c) in prev_chars.enumerate() {
+        for c in prev_chars {
             if !is_word(c) {
                 break;
             }
@@ -867,7 +870,7 @@ impl TextInput {
             start -= c.len_utf16();
         }
 
-        for (_, c) in next_chars.enumerate() {
+        for c in next_chars {
             if !is_word(c) {
                 break;
             }
@@ -1177,12 +1180,8 @@ impl Render for TextInput {
                     .on_action(cx.listener(Self::delete_to_end_of_line))
                     .on_action(cx.listener(Self::enter))
             })
-            .on_action(cx.listener(Self::up))
-            .on_action(cx.listener(Self::down))
             .on_action(cx.listener(Self::left))
             .on_action(cx.listener(Self::right))
-            .on_action(cx.listener(Self::select_up))
-            .on_action(cx.listener(Self::select_down))
             .on_action(cx.listener(Self::select_left))
             .on_action(cx.listener(Self::select_right))
             .on_action(cx.listener(Self::select_all))
@@ -1206,7 +1205,13 @@ impl Render for TextInput {
             .input_py(self.size)
             .input_h(self.size)
             .cursor_text()
-            .when(self.multi_line, |this| this.h_auto())
+            .when(self.multi_line, |this| {
+                this.on_action(cx.listener(Self::up))
+                    .on_action(cx.listener(Self::down))
+                    .on_action(cx.listener(Self::select_up))
+                    .on_action(cx.listener(Self::select_down))
+                    .h_auto()
+            })
             .when(self.appearance, |this| {
                 this.bg(if self.disabled {
                     cx.theme().muted
@@ -1249,7 +1254,7 @@ impl Render for TextInput {
                             .absolute()
                             .top_0()
                             .left_0()
-                            .right_0()
+                            .right(px(1.))
                             .bottom_0()
                             .child(
                                 Scrollbar::vertical(

crates/ui/src/input/mod.rs

@@ -2,6 +2,7 @@ mod blink_cursor;
 mod change;
 mod clear_button;
 mod element;
+#[allow(clippy::module_inception)]
 mod input;
 mod otp_input;
 

crates/ui/src/input/otp_input.rs

@@ -127,7 +127,7 @@ impl OtpInput {
             }
             _ => {
                 let c = key.chars().next().unwrap();
-                if !matches!(c, '0'..='9') {
+                if !c.is_ascii_digit() {
                     return;
                 }
                 if ix >= self.length {

crates/ui/src/link.rs

@@ -5,13 +5,15 @@ use gpui::{
 
 use crate::theme::ActiveTheme as _;
 
+type OnClick = Option<Box<dyn Fn(&ClickEvent, &mut gpui::WindowContext) + 'static>>;
+
 /// A Link element like a `<a>` tag in HTML.
 #[derive(IntoElement)]
 pub struct Link {
     base: Stateful<Div>,
     href: Option<SharedString>,
     disabled: bool,
-    on_click: Option<Box<dyn Fn(&ClickEvent, &mut gpui::WindowContext) + 'static>>,
+    on_click: OnClick,
 }
 
 impl Link {

crates/ui/src/list/list_item.rs

@@ -6,6 +6,10 @@ use gpui::{
 };
 use smallvec::SmallVec;
 
+type OnClick = Option<Box<dyn Fn(&ClickEvent, &mut WindowContext) + 'static>>;
+type OnMouseEnter = Option<Box<dyn Fn(&MouseMoveEvent, &mut WindowContext) + 'static>>;
+type Suffix = Option<Box<dyn Fn(&mut WindowContext) -> AnyElement + 'static>>;
+
 #[derive(IntoElement)]
 pub struct ListItem {
     id: ElementId,
@@ -14,9 +18,9 @@ pub struct ListItem {
     selected: bool,
     confirmed: bool,
     check_icon: Option<Icon>,
-    on_click: Option<Box<dyn Fn(&ClickEvent, &mut WindowContext) + 'static>>,
+    on_click: OnClick,
-    on_mouse_enter: Option<Box<dyn Fn(&MouseMoveEvent, &mut WindowContext) + 'static>>,
+    on_mouse_enter: OnMouseEnter,
-    suffix: Option<Box<dyn Fn(&mut WindowContext) -> AnyElement + 'static>>,
+    suffix: Suffix,
     children: SmallVec<[AnyElement; 2]>,
 }
 

crates/ui/src/list/mod.rs

@@ -1,3 +1,4 @@
+#[allow(clippy::module_inception)]
 mod list;
 mod list_item;
 

crates/ui/src/modal.rs

@@ -17,10 +17,13 @@ use crate::{
 actions!(modal, [Escape]);
 
 const CONTEXT: &str = "Modal";
+
 pub fn init(cx: &mut AppContext) {
     cx.bind_keys([KeyBinding::new("escape", Escape, Some(CONTEXT))])
 }
 
+type OnClose = Rc<dyn Fn(&ClickEvent, &mut WindowContext) + 'static>;
+
 #[derive(IntoElement)]
 pub struct Modal {
     base: Div,
@@ -30,8 +33,7 @@ pub struct Modal {
     width: Pixels,
     max_width: Option<Pixels>,
     margin_top: Option<Pixels>,
-
+    on_close: OnClose,
-    on_close: Rc<dyn Fn(&ClickEvent, &mut WindowContext) + 'static>,
     show_close: bool,
     overlay: bool,
     keyboard: bool,

crates/ui/src/notification.rs

@@ -40,6 +40,8 @@ impl From<(TypeId, ElementId)> for NotificationId {
     }
 }
 
+type OnClick = Option<Arc<dyn Fn(&ClickEvent, &mut WindowContext)>>;
+
 /// A notification element.
 pub struct Notification {
     /// The id is used make the notification unique.
@@ -52,7 +54,7 @@ pub struct Notification {
     message: SharedString,
     icon: Option<Icon>,
     autohide: bool,
-    on_click: Option<Arc<dyn Fn(&ClickEvent, &mut WindowContext)>>,
+    on_click: OnClick,
     closing: bool,
 }
 

crates/ui/src/popover.rs

@@ -17,9 +17,11 @@ pub fn init(cx: &mut AppContext) {
     cx.bind_keys([KeyBinding::new("escape", Escape, Some(CONTEXT))])
 }
 
+type Content<T> = Rc<dyn Fn(&mut ViewContext<T>) -> AnyElement>;
+
 pub struct PopoverContent {
     focus_handle: FocusHandle,
-    content: Rc<dyn Fn(&mut ViewContext<Self>) -> AnyElement>,
+    content: Content<Self>,
     max_width: Option<Pixels>,
 }
 
@@ -62,11 +64,14 @@ impl Render for PopoverContent {
     }
 }
 
+type Trigger = Option<Box<dyn FnOnce(bool, &WindowContext) -> AnyElement + 'static>>;
+type ViewContent<M> = Option<Rc<dyn Fn(&mut WindowContext) -> View<M> + 'static>>;
+
 pub struct Popover<M: ManagedView> {
     id: ElementId,
     anchor: AnchorCorner,
-    trigger: Option<Box<dyn FnOnce(bool, &WindowContext) -> AnyElement + 'static>>,
+    trigger: Trigger,
-    content: Option<Rc<dyn Fn(&mut WindowContext) -> View<M> + 'static>>,
+    content: ViewContent<M>,
     /// Style for trigger element.
     /// This is used for hotfix the trigger element style to support w_full.
     trigger_style: Option<StyleRefinement>,

crates/ui/src/popup_menu.rs

@@ -264,7 +264,7 @@ impl PopupMenu {
             // If the actions are listened on the `PanelContent`,
             // it can't receive the actions from the `PopupMenu`, unless we focus on `PanelContent`.
             if let Some(handle) = action_focus_handle.as_ref() {
-                cx.focus(&handle);
+                cx.focus(handle);
             }
 
             cx.dispatch_action(action.boxed_clone());
@@ -367,8 +367,7 @@ impl PopupMenu {
     }
 
     fn confirm(&mut self, _: &Confirm, cx: &mut ViewContext<Self>) {
-        match self.selected_index {
+        if let Some(index) = self.selected_index {
-            Some(index) => {
             let item = self.menu_items.get(index);
             match item {
                 Some(PopupMenuItem::Item { handler, .. }) => {
@@ -382,8 +381,6 @@ impl PopupMenu {
                 _ => {}
             }
         }
-            _ => {}
-        }
     }
 
     fn select_next(&mut self, _: &SelectNext, cx: &mut ViewContext<Self>) {
@@ -435,7 +432,7 @@ impl PopupMenu {
                 let el = div().text_color(cx.theme().muted_foreground).children(
                     keybinding
                         .keystrokes()
-                        .into_iter()
+                        .iter()
                         .map(|key| key_shortcut(key.clone())),
                 );
 
@@ -443,7 +440,7 @@ impl PopupMenu {
             }
         }
 
-        return None;
+        None
     }
 
     fn render_icon(

crates/ui/src/progress.rs

@@ -25,6 +25,12 @@ impl Progress {
     }
 }
 
+impl Default for Progress {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
 impl RenderOnce for Progress {
     fn render(self, cx: &mut WindowContext) -> impl IntoElement {
         let rounded = px(self.height / 2.);

crates/ui/src/radio.rs

@@ -4,6 +4,8 @@ use gpui::{
     ParentElement, RenderOnce, SharedString, StatefulInteractiveElement, Styled, WindowContext,
 };
 
+type OnClick = Option<Box<dyn Fn(&bool, &mut WindowContext) + 'static>>;
+
 /// A Radio element.
 ///
 /// This is not included the Radio group implementation, you can manage the group by yourself.
@@ -13,7 +15,7 @@ pub struct Radio {
     label: Option<SharedString>,
     checked: bool,
     disabled: bool,
-    on_click: Option<Box<dyn Fn(&bool, &mut WindowContext) + 'static>>,
+    on_click: OnClick,
 }
 
 impl Radio {

crates/ui/src/resizable/panel.rs

@@ -274,6 +274,8 @@ impl Render for ResizablePanelGroup {
     }
 }
 
+type ContentBuilder = Option<Rc<dyn Fn(&mut WindowContext) -> AnyElement>>;
+
 pub struct ResizablePanel {
     group: Option<WeakView<ResizablePanelGroup>>,
     /// Initial size is the size that the panel has when it is created.
@@ -283,7 +285,7 @@ pub struct ResizablePanel {
     /// the size ratio that the panel has relative to its group
     size_ratio: Option<f32>,
     axis: Axis,
-    content_builder: Option<Rc<dyn Fn(&mut WindowContext) -> AnyElement>>,
+    content_builder: ContentBuilder,
     content_view: Option<AnyView>,
     /// The bounds of the resizable panel, when render the bounds will be updated.
     bounds: Bounds<Pixels>,
@@ -435,7 +437,6 @@ impl Element for ResizePanelGroupElement {
         _: &mut Self::RequestLayoutState,
         _: &mut WindowContext,
     ) -> Self::PrepaintState {
-        ()
     }
 
     fn paint(

crates/ui/src/root.rs

@@ -69,7 +69,7 @@ impl ContextModal for WindowContext<'_> {
     }
 
     fn has_active_drawer(&self) -> bool {
-        Root::read(&self).active_drawer.is_some()
+        Root::read(self).active_drawer.is_some()
     }
 
     fn close_drawer(&mut self) {
@@ -87,7 +87,7 @@ impl ContextModal for WindowContext<'_> {
         Root::update(self, move |root, cx| {
             // Only save focus handle if there are no active modals.
             // This is used to restore focus when all modals are closed.
-            if root.active_modals.len() == 0 {
+            if root.active_modals.is_empty() {
                 root.previous_focus_handle = cx.focused();
             }
 
@@ -103,7 +103,7 @@ impl ContextModal for WindowContext<'_> {
     }
 
     fn has_active_modal(&self) -> bool {
-        Root::read(&self).active_modals.len() > 0
+        !Root::read(self).active_modals.is_empty()
     }
 
     fn close_modal(&mut self) {
@@ -145,7 +145,7 @@ impl ContextModal for WindowContext<'_> {
     }
 
     fn notifications(&self) -> Rc<Vec<View<Notification>>> {
-        Rc::new(Root::read(&self).notification.read(&self).notifications())
+        Rc::new(Root::read(self).notification.read(self).notifications())
     }
 }
 impl<V> ContextModal for ViewContext<'_, V> {
@@ -211,16 +211,19 @@ pub struct Root {
     view: AnyView,
 }
 
+type DrawerBuilder = Rc<dyn Fn(Drawer, &mut WindowContext) -> Drawer + 'static>;
+type ModelBuilder = Rc<dyn Fn(Modal, &mut WindowContext) -> Modal + 'static>;
+
 #[derive(Clone)]
 struct ActiveDrawer {
     focus_handle: FocusHandle,
-    builder: Rc<dyn Fn(Drawer, &mut WindowContext) -> Drawer + 'static>,
+    builder: DrawerBuilder,
 }
 
 #[derive(Clone)]
 struct ActiveModal {
     focus_handle: FocusHandle,
-    builder: Rc<dyn Fn(Modal, &mut WindowContext) -> Modal + 'static>,
+    builder: ModelBuilder,
 }
 
 impl Root {

crates/ui/src/scroll/scrollable.rs

@@ -150,11 +150,15 @@ where
         id: Option<&gpui::GlobalElementId>,
         cx: &mut gpui::WindowContext,
     ) -> (gpui::LayoutId, Self::RequestLayoutState) {
-        let mut style = Style::default();
+        let style = Style {
-        style.flex_grow = 1.0;
+            flex_grow: 1.0,
-        style.position = Position::Relative;
+            position: Position::Relative,
-        style.size.width = relative(1.0).into();
+            size: Size {
-        style.size.height = relative(1.0).into();
+                width: relative(1.0).into(),
+                height: relative(1.0).into(),
+            },
+            ..Default::default()
+        };
 
         let axis = self.axis;
         let view_id = self.view_id;

crates/ui/src/scroll/scrollable_mask.rs

@@ -70,13 +70,17 @@ impl Element for ScrollableMask {
         _: Option<&GlobalElementId>,
         cx: &mut WindowContext,
     ) -> (LayoutId, Self::RequestLayoutState) {
-        let mut style = Style::default();
         // Set the layout style relative to the table view to get same size.
-        style.position = Position::Absolute;
+        let style = Style {
-        style.flex_grow = 1.0;
+            position: Position::Absolute,
-        style.flex_shrink = 1.0;
+            flex_grow: 1.0,
-        style.size.width = relative(1.).into();
+            flex_shrink: 1.0,
-        style.size.height = relative(1.).into();
+            size: gpui::Size {
+                width: relative(1.).into(),
+                height: relative(1.).into(),
+            },
+            ..Default::default()
+        };
 
         (cx.request_layout(style, None), ())
     }

crates/ui/src/scroll/scrollbar.rs

@@ -2,14 +2,31 @@ use std::{cell::Cell, rc::Rc, time::Instant};
 
 use crate::theme::ActiveTheme;
 use gpui::{
-    fill, point, px, relative, Bounds, ContentMask, Edges, Element, EntityId, Hitbox, IntoElement,
+    fill, point, px, relative, AppContext, Bounds, ContentMask, CursorStyle, Edges, Element,
-    MouseDownEvent, MouseMoveEvent, MouseUpEvent, PaintQuad, Pixels, Point, Position, ScrollHandle,
+    EntityId, Hitbox, Hsla, IntoElement, MouseDownEvent, MouseMoveEvent, MouseUpEvent, PaintQuad,
-    ScrollWheelEvent, Style, UniformListScrollHandle,
+    Pixels, Point, Position, ScrollHandle, ScrollWheelEvent, Style, UniformListScrollHandle,
 };
+use serde::{Deserialize, Serialize};
+
+/// Scrollbar show mode.
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize, Hash, Default)]
+pub enum ScrollbarShow {
+    #[default]
+    Scrolling,
+    Hover,
+}
+
+impl ScrollbarShow {
+    fn is_hover(&self) -> bool {
+        matches!(self, Self::Hover)
+    }
+}
 
 const MIN_THUMB_SIZE: f32 = 80.;
 const THUMB_RADIUS: Pixels = Pixels(3.0);
 const THUMB_INSET: Pixels = Pixels(4.);
+const FADE_OUT_DURATION: f32 = 3.0;
+const FADE_OUT_DELAY: f32 = 2.0;
 
 pub trait ScrollHandleOffsetable {
     fn offset(&self) -> Point<Pixels>;
@@ -92,6 +109,9 @@ impl ScrollbarState {
     fn with_hovered(&self, axis: Option<ScrollbarAxis>) -> Self {
         let mut state = *self;
         state.hovered_axis = axis;
+        if self.is_scrollbar_visible() {
+            state.last_scroll_time = Some(Instant::now());
+        }
         state
     }
 
@@ -111,6 +131,21 @@ impl ScrollbarState {
         state.last_scroll_time = last_scroll_time;
         state
     }
+
+    fn with_last_scroll_time(&self, t: Option<Instant>) -> Self {
+        let mut state = *self;
+        state.last_scroll_time = t;
+        state
+    }
+
+    fn is_scrollbar_visible(&self) -> bool {
+        if let Some(last_time) = self.last_scroll_time {
+            let elapsed = Instant::now().duration_since(last_time).as_secs_f32();
+            elapsed < FADE_OUT_DURATION
+        } else {
+            false
+        }
+    }
 }
 
 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
@@ -257,6 +292,52 @@ impl Scrollbar {
         self.axis = axis;
         self
     }
+
+    fn style_for_active(cx: &AppContext) -> (Hsla, Hsla, Hsla, Pixels, Pixels) {
+        (
+            cx.theme().scrollbar_thumb_hover,
+            cx.theme().scrollbar,
+            cx.theme().border,
+            THUMB_INSET - px(1.),
+            THUMB_RADIUS,
+        )
+    }
+
+    fn style_for_hovered_thumb(cx: &AppContext) -> (Hsla, Hsla, Hsla, Pixels, Pixels) {
+        (
+            cx.theme().scrollbar_thumb_hover,
+            cx.theme().scrollbar,
+            cx.theme().border,
+            THUMB_INSET - px(1.),
+            THUMB_RADIUS,
+        )
+    }
+
+    fn style_for_hovered_bar(cx: &AppContext) -> (Hsla, Hsla, Hsla, Pixels, Pixels) {
+        let (inset, radius) = if cx.theme().scrollbar_show.is_hover() {
+            (THUMB_INSET, THUMB_RADIUS - px(1.))
+        } else {
+            (THUMB_INSET - px(1.), THUMB_RADIUS)
+        };
+
+        (
+            cx.theme().scrollbar_thumb,
+            cx.theme().scrollbar,
+            gpui::transparent_black(),
+            inset,
+            radius,
+        )
+    }
+
+    fn style_for_idle(_: &AppContext) -> (Hsla, Hsla, Hsla, Pixels, Pixels) {
+        (
+            gpui::transparent_black(),
+            gpui::transparent_black(),
+            gpui::transparent_black(),
+            THUMB_INSET,
+            THUMB_RADIUS - px(1.),
+        )
+    }
 }
 
 impl IntoElement for Scrollbar {
@@ -267,10 +348,31 @@ impl IntoElement for Scrollbar {
     }
 }
 
+pub struct PrepaintState {
+    hitbox: Hitbox,
+    states: Vec<AxisPrepaintState>,
+}
+
+pub struct AxisPrepaintState {
+    axis: ScrollbarAxis,
+    bar_hitbox: Hitbox,
+    bounds: Bounds<Pixels>,
+    border_width: Pixels,
+    radius: Pixels,
+    bg: Hsla,
+    border: Hsla,
+    thumb_bounds: Bounds<Pixels>,
+    thumb_bg: Hsla,
+    scroll_size: Pixels,
+    container_size: Pixels,
+    thumb_size: Pixels,
+    margin_end: Pixels,
+}
+
 impl Element for Scrollbar {
     type RequestLayoutState = ();
 
-    type PrepaintState = Hitbox;
+    type PrepaintState = PrepaintState;
 
     fn id(&self) -> Option<gpui::ElementId> {
         None
@@ -281,12 +383,16 @@ impl Element for Scrollbar {
         _: Option<&gpui::GlobalElementId>,
         cx: &mut gpui::WindowContext,
     ) -> (gpui::LayoutId, Self::RequestLayoutState) {
-        let mut style = Style::default();
+        let style = Style {
-        style.position = Position::Absolute;
+            position: Position::Absolute,
-        style.flex_grow = 1.0;
+            flex_grow: 1.0,
-        style.flex_shrink = 1.0;
+            flex_shrink: 1.0,
-        style.size.width = relative(1.).into();
+            size: gpui::Size {
-        style.size.height = relative(1.).into();
+                width: relative(1.).into(),
+                height: relative(1.).into(),
+            },
+            ..Default::default()
+        };
 
         (cx.request_layout(style, None), ())
     }
@@ -298,36 +404,26 @@ impl Element for Scrollbar {
         _: &mut Self::RequestLayoutState,
         cx: &mut gpui::WindowContext,
     ) -> Self::PrepaintState {
-        cx.with_content_mask(Some(ContentMask { bounds }), |cx| {
+        let hitbox = cx.with_content_mask(Some(ContentMask { bounds }), |cx| {
             cx.insert_hitbox(bounds, false)
-        })
+        });
-    }
+
+        let mut states = vec![];
 
-    fn paint(
-        &mut self,
-        _: Option<&gpui::GlobalElementId>,
-        _: Bounds<Pixels>,
-        _: &mut Self::RequestLayoutState,
-        hitbox: &mut Self::PrepaintState,
-        cx: &mut gpui::WindowContext,
-    ) {
-        let hitbox_bounds = hitbox.bounds;
         let mut has_both = self.axis.is_both();
 
         for axis in self.axis.all().into_iter() {
-            const NORMAL_OPACITY: f32 = 0.6;
-
             let is_vertical = axis.is_vertical();
             let (scroll_area_size, container_size, scroll_position) = if is_vertical {
                 (
                     self.scroll_size.height,
-                    hitbox_bounds.size.height,
+                    hitbox.size.height,
                     self.scroll_handle.offset().y,
                 )
             } else {
                 (
                     self.scroll_size.width,
-                    hitbox_bounds.size.width,
+                    hitbox.size.width,
                     self.scroll_handle.offset().x,
                 )
             };
@@ -354,23 +450,23 @@ impl Element for Scrollbar {
             let bounds = Bounds {
                 origin: if is_vertical {
                     point(
-                        hitbox_bounds.origin.x + hitbox_bounds.size.width - self.width,
+                        hitbox.origin.x + hitbox.size.width - self.width,
-                        hitbox_bounds.origin.y,
+                        hitbox.origin.y,
                     )
                 } else {
                     point(
-                        hitbox_bounds.origin.x,
+                        hitbox.origin.x,
-                        hitbox_bounds.origin.y + hitbox_bounds.size.height - self.width,
+                        hitbox.origin.y + hitbox.size.height - self.width,
                     )
                 },
                 size: gpui::Size {
                     width: if is_vertical {
                         self.width
                     } else {
-                        hitbox_bounds.size.width
+                        hitbox.size.width
                     },
                     height: if is_vertical {
-                        hitbox_bounds.size.height
+                        hitbox.size.height
                     } else {
                         self.width
                     },
@@ -378,49 +474,46 @@ impl Element for Scrollbar {
             };
 
             let state = self.state.clone();
+            let is_hover_to_show = cx.theme().scrollbar_show.is_hover();
+            let is_hovered_on_bar = state.get().hovered_axis == Some(axis);
+            let is_hovered_on_thumb = state.get().hovered_on_thumb == Some(axis);
+
             let (thumb_bg, bar_bg, bar_border, inset, radius) =
                 if state.get().dragged_axis == Some(axis) {
-                    (
+                    Self::style_for_active(cx)
-                        cx.theme().scrollbar_thumb,
+                } else if is_hover_to_show && is_hovered_on_bar {
-                        cx.theme().scrollbar,
+                    if is_hovered_on_thumb {
-                        cx.theme().border,
+                        Self::style_for_hovered_thumb(cx)
-                        THUMB_INSET - px(1.),
-                        THUMB_RADIUS,
-                    )
-                } else if state.get().hovered_axis == Some(axis) {
-                    if state.get().hovered_on_thumb == Some(axis) {
-                        (
-                            cx.theme().scrollbar_thumb,
-                            cx.theme().scrollbar,
-                            cx.theme().border,
-                            THUMB_INSET - px(1.),
-                            THUMB_RADIUS,
-                        )
                     } else {
-                        (
+                        Self::style_for_hovered_bar(cx)
-                            cx.theme().scrollbar_thumb.opacity(NORMAL_OPACITY),
-                            gpui::transparent_black(),
-                            gpui::transparent_black(),
-                            THUMB_INSET,
-                            THUMB_RADIUS,
-                        )
                     }
                 } else {
-                    let mut idle_state = (
+                    let mut idle_state = Self::style_for_idle(cx);
-                        gpui::transparent_black(),
+                    // Delay 2s to fade out the scrollbar thumb (in 1s)
-                        gpui::transparent_black(),
-                        gpui::transparent_black(),
-                        THUMB_INSET,
-                        THUMB_RADIUS - px(1.),
-                    );
                     if let Some(last_time) = state.get().last_scroll_time {
                         let elapsed = Instant::now().duration_since(last_time).as_secs_f32();
-                        if elapsed < 1.0 {
+                        if elapsed < FADE_OUT_DURATION {
-                            let y_value = NORMAL_OPACITY - elapsed.powi(10); // y = 1 - x^10
+                            if is_hovered_on_bar {
-                            idle_state.0 = cx.theme().scrollbar_thumb.opacity(y_value);
+                                state.set(state.get().with_last_scroll_time(Some(Instant::now())));
+                                idle_state = if is_hovered_on_thumb {
+                                    Self::style_for_hovered_thumb(cx)
+                                } else {
+                                    Self::style_for_hovered_bar(cx)
+                                };
+                            } else {
+                                if elapsed < FADE_OUT_DELAY {
+                                    idle_state.0 = cx.theme().scrollbar_thumb;
+                                } else {
+                                    // opacity = 1 - (x - 2)^10
+                                    let opacity = 1.0 - (elapsed - FADE_OUT_DELAY).powi(10);
+                                    idle_state.0 = cx.theme().scrollbar_thumb.opacity(opacity);
+                                };
+
                                 cx.request_animation_frame();
                             }
                         }
+                    }
+
                     idle_state
                 };
 
@@ -449,8 +542,57 @@ impl Element for Scrollbar {
                 )
             };
 
+            let bar_hitbox = cx.with_content_mask(Some(ContentMask { bounds }), |cx| {
+                cx.insert_hitbox(bounds, false)
+            });
+
+            states.push(AxisPrepaintState {
+                axis,
+                bar_hitbox,
+                bounds,
+                border_width,
+                radius,
+                bg: bar_bg,
+                border: bar_border,
+                thumb_bounds,
+                thumb_bg,
+                scroll_size: scroll_area_size,
+                container_size,
+                thumb_size: thumb_length,
+                margin_end,
+            })
+        }
+
+        PrepaintState { hitbox, states }
+    }
+
+    fn paint(
+        &mut self,
+        _: Option<&gpui::GlobalElementId>,
+        _: Bounds<Pixels>,
+        _: &mut Self::RequestLayoutState,
+        prepaint: &mut Self::PrepaintState,
+        cx: &mut gpui::WindowContext,
+    ) {
+        let hitbox_bounds = prepaint.hitbox.bounds;
+        let is_visible = self.state.get().is_scrollbar_visible();
+        let is_hover_to_show = cx.theme().scrollbar_show.is_hover();
+
+        for state in prepaint.states.iter() {
+            let axis = state.axis;
+            let radius = state.radius;
+            let bounds = state.bounds;
+            let thumb_bounds = state.thumb_bounds;
+            let scroll_area_size = state.scroll_size;
+            let container_size = state.container_size;
+            let thumb_size = state.thumb_size;
+            let margin_end = state.margin_end;
+            let is_vertical = axis.is_vertical();
+
+            cx.set_cursor_style(CursorStyle::default(), &state.bar_hitbox);
+
             cx.paint_layer(hitbox_bounds, |cx| {
-                cx.paint_quad(fill(bounds, bar_bg));
+                cx.paint_quad(fill(state.bounds, state.bg));
 
                 cx.paint_quad(PaintQuad {
                     bounds,
@@ -461,20 +603,20 @@ impl Element for Scrollbar {
                             top: px(0.),
                             right: px(0.),
                             bottom: px(0.),
-                            left: border_width,
+                            left: state.border_width,
                         }
                     } else {
                         Edges {
-                            top: border_width,
+                            top: state.border_width,
                             right: px(0.),
                             bottom: px(0.),
                             left: px(0.),
                         }
                     },
-                    border_color: bar_border,
+                    border_color: state.border,
                 });
 
-                cx.paint_quad(fill(thumb_bounds, thumb_bg).corner_radii(radius));
+                cx.paint_quad(fill(thumb_bounds, state.thumb_bg).corner_radii(radius));
             });
 
             cx.on_mouse_event({
@@ -483,8 +625,10 @@ impl Element for Scrollbar {
                 let scroll_handle = self.scroll_handle.clone();
 
                 move |event: &ScrollWheelEvent, phase, cx| {
-                    if phase.bubble() && hitbox_bounds.contains(&event.position) {
+                    if phase.bubble()
-                        if scroll_handle.offset() != state.get().last_scroll_offset {
+                        && hitbox_bounds.contains(&event.position)
+                        && scroll_handle.offset() != state.get().last_scroll_offset
+                    {
                         state.set(
                             state
                                 .get()
@@ -493,11 +637,11 @@ impl Element for Scrollbar {
                         cx.notify(Some(view_id));
                     }
                 }
-                }
             });
 
             let safe_range = (-scroll_area_size + container_size)..px(0.);
 
+            if is_hover_to_show || is_visible {
                 cx.on_mouse_event({
                     let state = self.state.clone();
                     let view_id = self.view_id;
@@ -519,11 +663,11 @@ impl Element for Scrollbar {
                                 // Set the thumb bar center to the click position
                                 let offset = scroll_handle.offset();
                                 let percentage = if is_vertical {
-                                (event.position.y - thumb_length / 2. - bounds.origin.y)
+                                    (event.position.y - thumb_size / 2. - bounds.origin.y)
-                                    / (bounds.size.height - thumb_length)
+                                        / (bounds.size.height - thumb_size)
                                 } else {
-                                (event.position.x - thumb_length / 2. - bounds.origin.x)
+                                    (event.position.x - thumb_size / 2. - bounds.origin.x)
-                                    / (bounds.size.width - thumb_length)
+                                        / (bounds.size.width - thumb_size)
                                 }
                                 .min(1.);
 
@@ -544,6 +688,7 @@ impl Element for Scrollbar {
                         }
                     }
                 });
+            }
 
             cx.on_mouse_event({
                 let scroll_handle = self.scroll_handle.clone();
@@ -557,14 +702,12 @@ impl Element for Scrollbar {
                             state.set(state.get().with_hovered(Some(axis)));
                             cx.notify(Some(view_id));
                         }
-                    } else {
+                    } else if state.get().hovered_axis == Some(axis)
-                        if state.get().hovered_axis == Some(axis) {
+                        && state.get().hovered_axis.is_some()
-                            if state.get().hovered_axis.is_some() {
+                    {
                         state.set(state.get().with_hovered(None));
                         cx.notify(Some(view_id));
                     }
-                        }
-                    }
 
                     // Update hovered state for scrollbar thumb
                     if thumb_bounds.contains(&event.position) {
@@ -572,12 +715,10 @@ impl Element for Scrollbar {
                             state.set(state.get().with_hovered_on_thumb(Some(axis)));
                             cx.notify(Some(view_id));
                         }
-                    } else {
+                    } else if state.get().hovered_on_thumb == Some(axis) {
-                        if state.get().hovered_on_thumb == Some(axis) {
                         state.set(state.get().with_hovered_on_thumb(None));
                         cx.notify(Some(view_id));
                     }
-                    }
 
                     // Move thumb position on dragging
                     if state.get().dragged_axis == Some(axis) && event.dragging() {
@@ -587,10 +728,10 @@ impl Element for Scrollbar {
 
                         let percentage = (if is_vertical {
                             (event.position.y - drag_pos.y - bounds.origin.y)
-                                / (bounds.size.height - thumb_length)
+                                / (bounds.size.height - thumb_size)
                         } else {
                             (event.position.x - drag_pos.x - bounds.origin.x)
-                                / (bounds.size.width - thumb_length - margin_end)
+                                / (bounds.size.width - thumb_size - margin_end)
                         })
                         .clamp(0., 1.);
 

crates/ui/src/sidebar/footer.rs

@@ -23,6 +23,13 @@ impl SidebarFooter {
         }
     }
 }
+
+impl Default for SidebarFooter {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
 impl Selectable for SidebarFooter {
     fn selected(mut self, selected: bool) -> Self {
         self.selected = selected;
@@ -33,6 +40,7 @@ impl Selectable for SidebarFooter {
         &self.id
     }
 }
+
 impl Collapsible for SidebarFooter {
     fn is_collapsed(&self) -> bool {
         self.is_collapsed
@@ -43,17 +51,21 @@ impl Collapsible for SidebarFooter {
         self
     }
 }
+
 impl ParentElement for SidebarFooter {
     fn extend(&mut self, elements: impl IntoIterator<Item = gpui::AnyElement>) {
         self.base.extend(elements);
     }
 }
+
 impl Styled for SidebarFooter {
     fn style(&mut self) -> &mut gpui::StyleRefinement {
         self.base.style()
     }
 }
+
 impl PopupMenuExt for SidebarFooter {}
+
 impl RenderOnce for SidebarFooter {
     fn render(self, cx: &mut gpui::WindowContext) -> impl gpui::IntoElement {
         h_flex()

crates/ui/src/sidebar/group.rs

@@ -33,6 +33,7 @@ impl<E: Collapsible + IntoElement> SidebarGroup<E> {
         self
     }
 }
+
 impl<E: Collapsible + IntoElement> Collapsible for SidebarGroup<E> {
     fn is_collapsed(&self) -> bool {
         self.is_collapsed
@@ -43,6 +44,7 @@ impl<E: Collapsible + IntoElement> Collapsible for SidebarGroup<E> {
         self
     }
 }
+
 impl<E: Collapsible + IntoElement> RenderOnce for SidebarGroup<E> {
     fn render(self, cx: &mut WindowContext) -> impl IntoElement {
         v_flex()

crates/ui/src/sidebar/header.rs

@@ -23,6 +23,13 @@ impl SidebarHeader {
         }
     }
 }
+
+impl Default for SidebarHeader {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
 impl Selectable for SidebarHeader {
     fn selected(mut self, selected: bool) -> Self {
         self.selected = selected;
@@ -33,6 +40,7 @@ impl Selectable for SidebarHeader {
         &self.id
     }
 }
+
 impl Collapsible for SidebarHeader {
     fn is_collapsed(&self) -> bool {
         self.is_collapsed
@@ -43,17 +51,21 @@ impl Collapsible for SidebarHeader {
         self
     }
 }
+
 impl ParentElement for SidebarHeader {
     fn extend(&mut self, elements: impl IntoIterator<Item = gpui::AnyElement>) {
         self.base.extend(elements);
     }
 }
+
 impl Styled for SidebarHeader {
     fn style(&mut self) -> &mut gpui::StyleRefinement {
         self.base.style()
     }
 }
+
 impl PopupMenuExt for SidebarHeader {}
+
 impl RenderOnce for SidebarHeader {
     fn render(self, cx: &mut gpui::WindowContext) -> impl gpui::IntoElement {
         h_flex()

crates/ui/src/sidebar/menu.rs

@@ -58,6 +58,13 @@ impl SidebarMenu {
         self
     }
 }
+
+impl Default for SidebarMenu {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
 impl Collapsible for SidebarMenu {
     fn is_collapsed(&self) -> bool {
         self.is_collapsed
@@ -84,20 +91,22 @@ impl RenderOnce for SidebarMenu {
     }
 }
 
+type Handler = Rc<dyn Fn(&ClickEvent, &mut WindowContext)>;
+
 /// A sidebar menu item
 #[derive(IntoElement)]
 enum SidebarMenuItem {
     Item {
         icon: Option<Icon>,
         label: SharedString,
-        handler: Rc<dyn Fn(&ClickEvent, &mut WindowContext)>,
+        handler: Handler,
         active: bool,
         is_collapsed: bool,
     },
     Submenu {
         icon: Option<Icon>,
         label: SharedString,
-        handler: Rc<dyn Fn(&ClickEvent, &mut WindowContext)>,
+        handler: Handler,
         items: Vec<SidebarMenuItem>,
         is_open: bool,
         is_collapsed: bool,

crates/ui/src/sidebar/mod.rs

@@ -106,13 +106,15 @@ impl<E: Collapsible + IntoElement> Sidebar<E> {
     }
 }
 
+type OnClick = Option<Rc<dyn Fn(&ClickEvent, &mut WindowContext)>>;
+
 /// Sidebar collapse button with Icon.
 #[derive(IntoElement)]
 pub struct SidebarToggleButton {
     btn: Button,
     is_collapsed: bool,
     side: Side,
-    on_click: Option<Rc<dyn Fn(&ClickEvent, &mut WindowContext)>>,
+    on_click: OnClick,
 }
 
 impl SidebarToggleButton {
@@ -158,12 +160,10 @@ impl RenderOnce for SidebarToggleButton {
             } else {
                 IconName::PanelRightOpen
             }
-        } else {
+        } else if self.side.is_left() {
-            if self.side.is_left() {
             IconName::PanelLeftClose
         } else {
             IconName::PanelRightClose
-            }
         };
 
         self.btn

crates/ui/src/skeleton.rs

@@ -18,6 +18,12 @@ impl Skeleton {
     }
 }
 
+impl Default for Skeleton {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
 impl Styled for Skeleton {
     fn style(&mut self) -> &mut gpui::StyleRefinement {
         self.base.style()

crates/ui/src/styled.rs

@@ -350,17 +350,17 @@ impl<T: Styled> StyleSized<T> for T {
 }
 
 pub trait AxisExt {
-    fn is_horizontal(self) -> bool;
+    fn is_horizontal(&self) -> bool;
-    fn is_vertical(self) -> bool;
+    fn is_vertical(&self) -> bool;
 }
 
 impl AxisExt for Axis {
-    fn is_horizontal(self) -> bool {
+    fn is_horizontal(&self) -> bool {
-        self == Axis::Horizontal
+        self == &Axis::Horizontal
     }
 
-    fn is_vertical(self) -> bool {
+    fn is_vertical(&self) -> bool {
-        self == Axis::Vertical
+        self == &Axis::Vertical
     }
 }
 
@@ -385,17 +385,11 @@ impl Display for Placement {
 
 impl Placement {
     pub fn is_horizontal(&self) -> bool {
-        match self {
+        matches!(self, Placement::Left | Placement::Right)
-            Placement::Left | Placement::Right => true,
-            _ => false,
-        }
     }
 
     pub fn is_vertical(&self) -> bool {
-        match self {
+        matches!(self, Placement::Top | Placement::Bottom)
-            Placement::Top | Placement::Bottom => true,
-            _ => false,
-        }
     }
 
     pub fn axis(&self) -> Axis {

crates/ui/src/svg_img.rs

@@ -184,6 +184,12 @@ impl SvgImg {
     }
 }
 
+impl Default for SvgImg {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
 impl IntoElement for SvgImg {
     type Element = Self;
 

crates/ui/src/switch.rs

@@ -6,13 +6,15 @@ use gpui::{
 };
 use std::{cell::RefCell, rc::Rc, time::Duration};
 
+type OnClick = Option<Rc<dyn Fn(&bool, &mut WindowContext)>>;
+
 pub struct Switch {
     id: ElementId,
     checked: bool,
     disabled: bool,
     label: Option<SharedString>,
     label_side: Side,
-    on_click: Option<Rc<dyn Fn(&bool, &mut WindowContext)>>,
+    on_click: OnClick,
     size: Size,
 }
 

crates/ui/src/tab.rs

@@ -1,3 +1,4 @@
+#[allow(clippy::module_inception)]
 mod tab;
 mod tab_bar;
 

crates/ui/src/theme.rs

@@ -1,9 +1,10 @@
-use std::ops::{Deref, DerefMut};
-
 use gpui::{
     hsla, point, AppContext, BoxShadow, Global, Hsla, ModelContext, Pixels, SharedString,
     ViewContext, WindowAppearance, WindowContext,
 };
+use std::ops::{Deref, DerefMut};
+
+use crate::scroll::ScrollbarShow;
 
 pub fn init(cx: &mut AppContext) {
     Theme::sync_system_appearance(cx)
@@ -117,15 +118,19 @@ impl Colorize for Hsla {
     }
 
     /// Return a new color with the lightness increased by the given factor.
+    ///
+    /// factor range: 0.0 .. 1.0
     fn lighten(&self, factor: f32) -> Hsla {
-        let l = self.l + (1.0 - self.l) * factor.clamp(0.0, 1.0).min(1.0);
+        let l = self.l * (1.0 + factor.clamp(0.0, 1.0));
 
         Hsla { l, ..*self }
     }
 
     /// Return a new color with the darkness increased by the given factor.
+    ///
+    /// factor range: 0.0 .. 1.0
     fn darken(&self, factor: f32) -> Hsla {
-        let l = self.l * (1.0 - factor.clamp(0.0, 1.0).min(1.0));
+        let l = self.l * (1.0 - factor.clamp(0.0, 1.0));
 
         Hsla { l, ..*self }
     }
@@ -181,6 +186,7 @@ pub struct ThemeColor {
     pub ring: Hsla,
     pub scrollbar: Hsla,
     pub scrollbar_thumb: Hsla,
+    pub scrollbar_thumb_hover: Hsla,
     pub secondary: Hsla,
     pub secondary_active: Hsla,
     pub secondary_foreground: Hsla,
@@ -253,8 +259,9 @@ impl ThemeColor {
             primary_hover: hsl(223.0, 5.9, 15.0),
             progress_bar: hsl(223.0, 5.9, 10.0),
             ring: hsl(240.0, 5.9, 65.0),
-            scrollbar: hsl(0., 0., 97.).opacity(0.3),
+            scrollbar: hsl(0., 0., 97.).opacity(0.75),
-            scrollbar_thumb: hsl(0., 0., 69.),
+            scrollbar_thumb: hsl(0., 0., 69.).opacity(0.9),
+            scrollbar_thumb_hover: hsl(0., 0., 59.),
             secondary: hsl(240.0, 5.9, 96.9),
             secondary_active: hsl(240.0, 5.9, 93.),
             secondary_foreground: hsl(240.0, 59.0, 10.),
@@ -327,8 +334,9 @@ impl ThemeColor {
             primary_hover: hsl(223.0, 0.0, 90.0),
             progress_bar: hsl(223.0, 0.0, 98.0),
             ring: hsl(240.0, 4.9, 83.9),
-            scrollbar: hsl(240., 1., 15.).opacity(0.3),
+            scrollbar: hsl(240., 1., 15.).opacity(0.75),
-            scrollbar_thumb: hsl(0., 0., 68.),
+            scrollbar_thumb: hsl(0., 0., 48.).opacity(0.9),
+            scrollbar_thumb_hover: hsl(0., 0., 68.),
             secondary: hsl(240.0, 0., 13.0),
             secondary_active: hsl(240.0, 0., 10.),
             secondary_foreground: hsl(0.0, 0.0, 78.0),
@@ -373,6 +381,8 @@ pub struct Theme {
     pub radius: f32,
     pub shadow: bool,
     pub transparent: Hsla,
+    /// Show the scrollbar mode, default: Scrolling
+    pub scrollbar_show: ScrollbarShow,
 }
 
 impl Deref for Theme {
@@ -434,6 +444,7 @@ impl Theme {
         // self.selection = self.selection.apply(mask_color);
         self.scrollbar = self.scrollbar.apply(mask_color);
         self.scrollbar_thumb = self.scrollbar_thumb.apply(mask_color);
+        self.scrollbar_thumb_hover = self.scrollbar_thumb_hover.apply(mask_color);
         self.panel = self.panel.apply(mask_color);
         self.drag_border = self.drag_border.apply(mask_color);
         self.drop_target = self.drop_target.apply(mask_color);
@@ -518,6 +529,7 @@ impl From<ThemeColor> for Theme {
             },
             radius: 4.0,
             shadow: true,
+            scrollbar_show: ScrollbarShow::default(),
             colors,
         }
     }
@@ -535,3 +547,28 @@ impl ThemeMode {
         matches!(self, Self::Dark)
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use crate::theme::Colorize as _;
+
+    #[test]
+    fn test_lighten() {
+        let color = super::hsl(240.0, 5.0, 30.0);
+        let color = color.lighten(0.5);
+        assert_eq!(color.l, 0.45000002);
+        let color = color.lighten(0.5);
+        assert_eq!(color.l, 0.675);
+        let color = color.lighten(0.1);
+        assert_eq!(color.l, 0.7425);
+    }
+
+    #[test]
+    fn test_darken() {
+        let color = super::hsl(240.0, 5.0, 96.0);
+        let color = color.darken(0.5);
+        assert_eq!(color.l, 0.48);
+        let color = color.darken(0.5);
+        assert_eq!(color.l, 0.24);
+    }
+}

crates/ui/src/title_bar.rs

@@ -13,6 +13,8 @@ const TITLE_BAR_LEFT_PADDING: Pixels = px(80.);
 #[cfg(not(target_os = "macos"))]
 const TITLE_BAR_LEFT_PADDING: Pixels = px(12.);
 
+type OnCloseWindow = Option<Rc<Box<dyn Fn(&ClickEvent, &mut WindowContext)>>>;
+
 /// TitleBar used to customize the appearance of the title bar.
 ///
 /// We can put some elements inside the title bar.
@@ -20,7 +22,7 @@ const TITLE_BAR_LEFT_PADDING: Pixels = px(12.);
 pub struct TitleBar {
     base: Stateful<Div>,
     children: Vec<AnyElement>,
-    on_close_window: Option<Rc<Box<dyn Fn(&ClickEvent, &mut WindowContext)>>>,
+    on_close_window: OnCloseWindow,
 }
 
 impl TitleBar {
@@ -45,6 +47,12 @@ impl TitleBar {
     }
 }
 
+impl Default for TitleBar {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
 // The Windows control buttons have a fixed width of 35px.
 //
 // We don't need implementation the click event for the control buttons.
@@ -54,9 +62,7 @@ enum ControlIcon {
     Minimize,
     Restore,
     Maximize,
-    Close {
+    Close { on_close_window: OnCloseWindow },
-        on_close_window: Option<Rc<Box<dyn Fn(&ClickEvent, &mut WindowContext)>>>,
-    },
 }
 
 impl ControlIcon {
@@ -72,7 +78,7 @@ impl ControlIcon {
         Self::Maximize
     }
 
-    fn close(on_close_window: Option<Rc<Box<dyn Fn(&ClickEvent, &mut WindowContext)>>>) -> Self {
+    fn close(on_close_window: OnCloseWindow) -> Self {
         Self::Close { on_close_window }
     }
 
@@ -173,7 +179,7 @@ impl RenderOnce for ControlIcon {
 
 #[derive(IntoElement)]
 struct WindowControls {
-    on_close_window: Option<Rc<Box<dyn Fn(&ClickEvent, &mut WindowContext)>>>,
+    on_close_window: OnCloseWindow,
 }
 
 impl RenderOnce for WindowControls {
@@ -230,9 +236,9 @@ impl RenderOnce for TitleBar {
                     .items_center()
                     .justify_between()
                     .h(HEIGHT)
-                    .border_b_1()
-                    .border_color(cx.theme().title_bar_border)
                     .bg(cx.theme().title_bar)
+                    .border_b_1()
+                    .border_color(cx.theme().title_bar_border.opacity(0.7))
                     .when(cx.is_fullscreen(), |this| this.pl(px(12.)))
                     .on_double_click(|_, cx| cx.zoom_window())
                     .child(
@@ -286,13 +292,18 @@ impl Element for TitleBarElement {
         _: Option<&gpui::GlobalElementId>,
         cx: &mut WindowContext,
     ) -> (gpui::LayoutId, Self::RequestLayoutState) {
-        let mut style = Style::default();
+        let style = Style {
-        style.flex_grow = 1.0;
+            flex_grow: 1.0,
-        style.flex_shrink = 1.0;
+            flex_shrink: 1.0,
-        style.size.width = relative(1.).into();
+            size: gpui::Size {
-        style.size.height = relative(1.).into();
+                width: relative(1.).into(),
+                height: relative(1.).into(),
+            },
+            ..Default::default()
+        };
 
         let id = cx.request_layout(style, []);
+
         (id, ())
     }
 

crates/ui/src/tooltip.rs

@@ -10,6 +10,7 @@ pub struct Tooltip {
 }
 
 impl Tooltip {
+    #[allow(clippy::new_ret_no_self)]
     pub fn new(text: impl Into<SharedString>, cx: &mut WindowContext) -> AnyView {
         cx.new_view(|_| Self { text: text.into() }).into()
     }