Hide the mouse when the user is typing in the editor - take 2 (#27519)

Closes #4461

Take 2 on https://github.com/zed-industries/zed/pull/25040. 

Fixes panic caused due to using `setHiddenUntilMouseMoves` return type
to `set` cursor on macOS.

Release Notes:

- Now cursor hides when the user is typing in editor. It will stay
hidden until it is moved again. This behavior is `true` by default, and
can be configured with `hide_mouse_while_typing` in settings.

---------

Co-authored-by: Peter Tripp <peter@zed.dev>
Co-authored-by: Thomas Mickley-Doyle <thomas@zed.dev>
Co-authored-by: Agus <agus@zed.dev>
Co-authored-by: Kirill Bulatov <kirill@zed.dev>
Co-authored-by: Agus Zubiaga <hi@aguz.me>
Co-authored-by: Angelk90 <angelo.k90@hotmail.it>

crates/gpui/src/platform/linux/platform.rs

@@ -666,6 +666,12 @@ impl CursorStyle {
             CursorStyle::DragLink => "alias",
             CursorStyle::DragCopy => "copy",
             CursorStyle::ContextualMenu => "context-menu",
+            CursorStyle::None => {
+                #[cfg(debug_assertions)]
+                panic!("CursorStyle::None should be handled separately in the client");
+                #[cfg(not(debug_assertions))]
+                "default"
+            }
         }
         .to_string()
     }

crates/gpui/src/platform/linux/wayland.rs

@@ -35,6 +35,12 @@ impl CursorStyle {
             CursorStyle::DragLink => Shape::Alias,
             CursorStyle::DragCopy => Shape::Copy,
             CursorStyle::ContextualMenu => Shape::ContextMenu,
+            CursorStyle::None => {
+                #[cfg(debug_assertions)]
+                panic!("CursorStyle::None should be handled separately in the client");
+                #[cfg(not(debug_assertions))]
+                Shape::Default
+            }
         }
     }
 }

crates/gpui/src/platform/linux/wayland/client.rs

@@ -667,7 +667,13 @@ impl LinuxClient for WaylandClient {
             let serial = state.serial_tracker.get(SerialKind::MouseEnter);
             state.cursor_style = Some(style);
 
-            if let Some(cursor_shape_device) = &state.cursor_shape_device {
+            if let CursorStyle::None = style {
+                let wl_pointer = state
+                    .wl_pointer
+                    .clone()
+                    .expect("window is focused by pointer");
+                wl_pointer.set_cursor(serial, None, 0, 0);
+            } else if let Some(cursor_shape_device) = &state.cursor_shape_device {
                 cursor_shape_device.set_shape(serial, style.to_shape());
             } else if let Some(focused_window) = &state.mouse_focused_window {
                 // cursor-shape-v1 isn't supported, set the cursor using a surface.

crates/gpui/src/platform/linux/x11/client.rs

@@ -1438,13 +1438,16 @@ impl LinuxClient for X11Client {
         let cursor = match state.cursor_cache.get(&style) {
             Some(cursor) => *cursor,
             None => {
-                let Some(cursor) = state
-                    .cursor_handle
-                    .load_cursor(&state.xcb_connection, &style.to_icon_name())
-                    .log_err()
-                else {
+                let Some(cursor) = (match style {
+                    CursorStyle::None => create_invisible_cursor(&state.xcb_connection).log_err(),
+                    _ => state
+                        .cursor_handle
+                        .load_cursor(&state.xcb_connection, &style.to_icon_name())
+                        .log_err(),
+                }) else {
                     return;
                 };
+
                 state.cursor_cache.insert(style, cursor);
                 cursor
             }
@@ -1938,3 +1941,19 @@ fn make_scroll_wheel_event(
         touch_phase: TouchPhase::default(),
     }
 }
+
+fn create_invisible_cursor(
+    connection: &XCBConnection,
+) -> anyhow::Result<crate::platform::linux::x11::client::xproto::Cursor> {
+    let empty_pixmap = connection.generate_id()?;
+    let root = connection.setup().roots[0].root;
+    connection.create_pixmap(1, empty_pixmap, root, 1, 1)?;
+
+    let cursor = connection.generate_id()?;
+    connection.create_cursor(cursor, empty_pixmap, empty_pixmap, 0, 0, 0, 0, 0, 0, 0, 0)?;
+
+    connection.free_pixmap(empty_pixmap)?;
+
+    connection.flush()?;
+    Ok(cursor)
+}

crates/gpui/src/platform/mac/platform.rs

@@ -891,6 +891,11 @@ impl Platform for MacPlatform {
     /// in macOS's [NSCursor](https://developer.apple.com/documentation/appkit/nscursor).
     fn set_cursor_style(&self, style: CursorStyle) {
         unsafe {
+            if style == CursorStyle::None {
+                let _: () = msg_send![class!(NSCursor), setHiddenUntilMouseMoves:YES];
+                return;
+            }
+
             let new_cursor: id = match style {
                 CursorStyle::Arrow => msg_send![class!(NSCursor), arrowCursor],
                 CursorStyle::IBeam => msg_send![class!(NSCursor), IBeamCursor],
@@ -925,6 +930,7 @@ impl Platform for MacPlatform {
                 CursorStyle::DragLink => msg_send![class!(NSCursor), dragLinkCursor],
                 CursorStyle::DragCopy => msg_send![class!(NSCursor), dragCopyCursor],
                 CursorStyle::ContextualMenu => msg_send![class!(NSCursor), contextualMenuCursor],
+                CursorStyle::None => unreachable!(),
             };
 
             let old_cursor: id = msg_send![class!(NSCursor), currentCursor];

crates/gpui/src/platform/windows/events.rs

@@ -1127,7 +1127,19 @@ fn handle_nc_mouse_up_msg(
 }
 
 fn handle_cursor_changed(lparam: LPARAM, state_ptr: Rc<WindowsWindowStatePtr>) -> Option<isize> {
-    state_ptr.state.borrow_mut().current_cursor = HCURSOR(lparam.0 as _);
+    let mut state = state_ptr.state.borrow_mut();
+    let had_cursor = state.current_cursor.is_some();
+
+    state.current_cursor = if lparam.0 == 0 {
+        None
+    } else {
+        Some(HCURSOR(lparam.0 as _))
+    };
+
+    if had_cursor != state.current_cursor.is_some() {
+        unsafe { SetCursor(state.current_cursor) };
+    }
+
     Some(0)
 }
 
@@ -1138,7 +1150,9 @@ fn handle_set_cursor(lparam: LPARAM, state_ptr: Rc<WindowsWindowStatePtr>) -> Op
     ) {
         return None;
     }
-    unsafe { SetCursor(Some(state_ptr.state.borrow().current_cursor)) };
+    unsafe {
+        SetCursor(state_ptr.state.borrow().current_cursor);
+    };
     Some(1)
 }
 

crates/gpui/src/platform/windows/platform.rs

@@ -54,7 +54,7 @@ pub(crate) struct WindowsPlatformState {
     menus: Vec<OwnedMenu>,
     dock_menu_actions: Vec<Box<dyn Action>>,
     // NOTE: standard cursor handles don't need to close.
-    pub(crate) current_cursor: HCURSOR,
+    pub(crate) current_cursor: Option<HCURSOR>,
 }
 
 #[derive(Default)]
@@ -558,11 +558,11 @@ impl Platform for WindowsPlatform {
     fn set_cursor_style(&self, style: CursorStyle) {
         let hcursor = load_cursor(style);
         let mut lock = self.state.borrow_mut();
-        if lock.current_cursor.0 != hcursor.0 {
+        if lock.current_cursor.map(|c| c.0) != hcursor.map(|c| c.0) {
             self.post_message(
                 WM_GPUI_CURSOR_STYLE_CHANGED,
                 WPARAM(0),
-                LPARAM(hcursor.0 as isize),
+                LPARAM(hcursor.map_or(0, |c| c.0 as isize)),
             );
             lock.current_cursor = hcursor;
         }
@@ -683,7 +683,7 @@ impl Drop for WindowsPlatform {
 pub(crate) struct WindowCreationInfo {
     pub(crate) icon: HICON,
     pub(crate) executor: ForegroundExecutor,
-    pub(crate) current_cursor: HCURSOR,
+    pub(crate) current_cursor: Option<HCURSOR>,
     pub(crate) windows_version: WindowsVersion,
     pub(crate) validation_number: usize,
     pub(crate) main_receiver: flume::Receiver<Runnable>,

crates/gpui/src/platform/windows/util.rs

@@ -106,7 +106,7 @@ pub(crate) fn windows_credentials_target_name(url: &str) -> String {
     format!("zed:url={}", url)
 }
 
-pub(crate) fn load_cursor(style: CursorStyle) -> HCURSOR {
+pub(crate) fn load_cursor(style: CursorStyle) -> Option<HCURSOR> {
     static ARROW: OnceLock<SafeCursor> = OnceLock::new();
     static IBEAM: OnceLock<SafeCursor> = OnceLock::new();
     static CROSS: OnceLock<SafeCursor> = OnceLock::new();
@@ -127,17 +127,20 @@ pub(crate) fn load_cursor(style: CursorStyle) -> HCURSOR {
         | CursorStyle::ResizeUpDown
         | CursorStyle::ResizeRow => (&SIZENS, IDC_SIZENS),
         CursorStyle::OperationNotAllowed => (&NO, IDC_NO),
+        CursorStyle::None => return None,
         _ => (&ARROW, IDC_ARROW),
     };
-    *(*lock.get_or_init(|| {
-        HCURSOR(
-            unsafe { LoadImageW(None, name, IMAGE_CURSOR, 0, 0, LR_DEFAULTSIZE | LR_SHARED) }
-                .log_err()
-                .unwrap_or_default()
-                .0,
-        )
-        .into()
-    }))
+    Some(
+        *(*lock.get_or_init(|| {
+            HCURSOR(
+                unsafe { LoadImageW(None, name, IMAGE_CURSOR, 0, 0, LR_DEFAULTSIZE | LR_SHARED) }
+                    .log_err()
+                    .unwrap_or_default()
+                    .0,
+            )
+            .into()
+        })),
+    )
 }
 
 /// This function is used to configure the dark mode for the window built-in title bar.

crates/gpui/src/platform/windows/window.rs

@@ -48,7 +48,7 @@ pub struct WindowsWindowState {
 
     pub click_state: ClickState,
     pub system_settings: WindowsSystemSettings,
-    pub current_cursor: HCURSOR,
+    pub current_cursor: Option<HCURSOR>,
     pub nc_button_pressed: Option<u32>,
 
     pub display: WindowsDisplay,
@@ -76,7 +76,7 @@ impl WindowsWindowState {
         hwnd: HWND,
         transparent: bool,
         cs: &CREATESTRUCTW,
-        current_cursor: HCURSOR,
+        current_cursor: Option<HCURSOR>,
         display: WindowsDisplay,
         gpu_context: &BladeContext,
     ) -> Result<Self> {
@@ -351,7 +351,7 @@ struct WindowCreateContext<'a> {
     transparent: bool,
     is_movable: bool,
     executor: ForegroundExecutor,
-    current_cursor: HCURSOR,
+    current_cursor: Option<HCURSOR>,
     windows_version: WindowsVersion,
     validation_number: usize,
     main_receiver: flume::Receiver<Runnable>,