Refactor window errors

src/error.rs

@@ -2,22 +2,6 @@ use std::{error, fmt};
 
 use crate::platform_impl;
 
-// TODO: Rename
-/// An error that may be generated when requesting Winit state
-#[derive(Debug)]
-pub enum ExternalError {
-    /// The operation is not supported by the backend.
-    NotSupported(NotSupportedError),
-    /// The OS cannot perform the operation.
-    Os(OsError),
-}
-
-/// The error type for when the requested operation is not supported by the backend.
-#[derive(Clone)]
-pub struct NotSupportedError {
-    _marker: (),
-}
-
 /// The error type for when the OS cannot perform the requested operation.
 #[derive(Debug)]
 pub struct OsError {
@@ -26,14 +10,6 @@ pub struct OsError {
     error: platform_impl::OsError,
 }
 
-impl NotSupportedError {
-    #[inline]
-    #[allow(dead_code)]
-    pub(crate) fn new() -> NotSupportedError {
-        NotSupportedError { _marker: () }
-    }
-}
-
 impl OsError {
     #[allow(dead_code)]
     pub(crate) fn new(line: u32, file: &'static str, error: platform_impl::OsError) -> OsError {
@@ -57,49 +33,4 @@ impl fmt::Display for OsError {
     }
 }
 
-impl fmt::Display for ExternalError {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> Result<(), fmt::Error> {
-        match self {
-            ExternalError::NotSupported(e) => e.fmt(f),
-            ExternalError::Os(e) => e.fmt(f),
-        }
-    }
-}
-
-impl fmt::Debug for NotSupportedError {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> Result<(), fmt::Error> {
-        f.debug_struct("NotSupportedError").finish()
-    }
-}
-
-impl fmt::Display for NotSupportedError {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> Result<(), fmt::Error> {
-        f.pad("the requested operation is not supported by Winit")
-    }
-}
-
 impl error::Error for OsError {}
-impl error::Error for ExternalError {}
-impl error::Error for NotSupportedError {}
-
-#[cfg(test)]
-mod tests {
-    #![allow(clippy::redundant_clone)]
-
-    use super::*;
-
-    // Eat attributes for testing
-    #[test]
-    fn ensure_fmt_does_not_panic() {
-        let _ = format!(
-            "{:?}, {}",
-            NotSupportedError::new(),
-            NotSupportedError::new().clone()
-        );
-        let _ = format!(
-            "{:?}, {}",
-            ExternalError::NotSupported(NotSupportedError::new()),
-            ExternalError::NotSupported(NotSupportedError::new())
-        );
-    }
-}

src/platform/startup_notify.rs

@@ -22,8 +22,9 @@
 //! [`here`]: https://specifications.freedesktop.org/startup-notification-spec/startup-notification-latest.txt
 
 use std::env;
+use std::error::Error;
+use std::fmt;
 
-use crate::error::NotSupportedError;
 use crate::event_loop::{AsyncRequestSerial, EventLoopWindowTarget};
 use crate::window::{ActivationToken, Window, WindowBuilder};
 
@@ -33,6 +34,28 @@ const X11_VAR: &str = "DESKTOP_STARTUP_ID";
 /// The variable which is used mostly on Wayland.
 const WAYLAND_VAR: &str = "XDG_ACTIVATION_TOKEN";
 
+/// The error type for when the requested operation is not supported by the backend.
+#[derive(Debug)]
+pub struct ActivationTokenNotFound {
+    _marker: (),
+}
+
+impl fmt::Display for ActivationTokenNotFound {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> Result<(), fmt::Error> {
+        write!(f, "the requested operation is not supported by Winit")
+    }
+}
+
+impl ActivationTokenNotFound {
+    #[inline]
+    #[allow(dead_code)]
+    pub(crate) fn new() -> ActivationTokenNotFound {
+        ActivationTokenNotFound { _marker: () }
+    }
+}
+
+impl Error for ActivationTokenNotFound {}
+
 pub trait EventLoopExtStartupNotify {
     /// Read the token from the environment.
     ///
@@ -44,7 +67,7 @@ pub trait WindowExtStartupNotify {
     /// Request a new activation token.
     ///
     /// The token will be delivered inside
-    fn request_activation_token(&self) -> Result<AsyncRequestSerial, NotSupportedError>;
+    fn request_activation_token(&self) -> Result<AsyncRequestSerial, ActivationTokenNotFound>;
 }
 
 pub trait WindowBuilderExtStartupNotify {
@@ -69,7 +92,7 @@ impl<T> EventLoopExtStartupNotify for EventLoopWindowTarget<T> {
 }
 
 impl WindowExtStartupNotify for Window {
-    fn request_activation_token(&self) -> Result<AsyncRequestSerial, NotSupportedError> {
+    fn request_activation_token(&self) -> Result<AsyncRequestSerial, ActivationTokenNotFound> {
         self.window.request_activation_token()
     }
 }

src/platform_impl/android/mod.rs

@@ -22,15 +22,16 @@ use raw_window_handle::{
 use crate::platform_impl::Fullscreen;
 use crate::{
     dpi::{PhysicalPosition, PhysicalSize, Position, Size},
-    error,
+    error::OsError,
     event::{self, InnerSizeWriter, StartCause},
     event_loop::{
         self, ControlFlow, EventLoopCreationError, EventLoopRunError,
         EventLoopWindowTarget as RootELW,
     },
     platform::pump_events::PumpStatus,
     window::{
-        self, CursorGrabMode, ImePurpose, ResizeDirection, Theme, WindowButtons, WindowLevel,
+        self, CursorGrabMode, ImePurpose, NotSupportedError, ResizeDirection, Theme, WindowButtons,
+        WindowError, WindowLevel,
     },
 };
 
@@ -794,7 +795,7 @@ impl Window {
         el: &EventLoopWindowTarget<T>,
         _window_attrs: window::WindowAttributes,
         _: PlatformSpecificWindowBuilderAttributes,
-    ) -> Result<Self, error::OsError> {
+    ) -> Result<Self, OsError> {
         // FIXME this ignores requested window attributes
 
         Ok(Self {
@@ -839,12 +840,12 @@ impl Window {
 
     pub fn pre_present_notify(&self) {}
 
-    pub fn inner_position(&self) -> Result<PhysicalPosition<i32>, error::NotSupportedError> {
-        Err(error::NotSupportedError::new())
+    pub fn inner_position(&self) -> Result<PhysicalPosition<i32>, NotSupportedError> {
+        Err(NotSupportedError::new())
     }
 
-    pub fn outer_position(&self) -> Result<PhysicalPosition<i32>, error::NotSupportedError> {
-        Err(error::NotSupportedError::new())
+    pub fn outer_position(&self) -> Result<PhysicalPosition<i32>, NotSupportedError> {
+        Err(NotSupportedError::new())
     }
 
     pub fn set_outer_position(&self, _position: Position) {
@@ -937,39 +938,26 @@ impl Window {
 
     pub fn set_cursor_icon(&self, _: window::CursorIcon) {}
 
-    pub fn set_cursor_position(&self, _: Position) -> Result<(), error::ExternalError> {
-        Err(error::ExternalError::NotSupported(
-            error::NotSupportedError::new(),
-        ))
+    pub fn set_cursor_position(&self, _: Position) -> Result<(), WindowError> {
+        Err(WindowError::NotSupported(NotSupportedError::new()))
     }
 
-    pub fn set_cursor_grab(&self, _: CursorGrabMode) -> Result<(), error::ExternalError> {
-        Err(error::ExternalError::NotSupported(
-            error::NotSupportedError::new(),
-        ))
+    pub fn set_cursor_grab(&self, _: CursorGrabMode) -> Result<(), WindowError> {
+        Err(WindowError::NotSupported(NotSupportedError::new()))
     }
 
     pub fn set_cursor_visible(&self, _: bool) {}
 
-    pub fn drag_window(&self) -> Result<(), error::ExternalError> {
-        Err(error::ExternalError::NotSupported(
-            error::NotSupportedError::new(),
-        ))
+    pub fn drag_window(&self) -> Result<(), WindowError> {
+        Err(WindowError::NotSupported(NotSupportedError::new()))
     }
 
-    pub fn drag_resize_window(
-        &self,
-        _direction: ResizeDirection,
-    ) -> Result<(), error::ExternalError> {
-        Err(error::ExternalError::NotSupported(
-            error::NotSupportedError::new(),
-        ))
+    pub fn drag_resize_window(&self, _direction: ResizeDirection) -> Result<(), WindowError> {
+        Err(WindowError::NotSupported(NotSupportedError::new()))
     }
 
-    pub fn set_cursor_hittest(&self, _hittest: bool) -> Result<(), error::ExternalError> {
-        Err(error::ExternalError::NotSupported(
-            error::NotSupportedError::new(),
-        ))
+    pub fn set_cursor_hittest(&self, _hittest: bool) -> Result<(), WindowError> {
+        Err(WindowError::NotSupported(NotSupportedError::new()))
     }
 
     pub fn raw_window_handle(&self) -> RawWindowHandle {

src/platform_impl/ios/window.rs

@@ -13,16 +13,17 @@ use super::uikit::{UIApplication, UIScreen, UIScreenOverscanCompensation};
 use super::view::{WinitUIWindow, WinitView, WinitViewController};
 use crate::{
     dpi::{self, LogicalPosition, LogicalSize, PhysicalPosition, PhysicalSize, Position, Size},
-    error::{ExternalError, NotSupportedError, OsError as RootOsError},
+    error::OsError as RootOsError,
     event::{Event, WindowEvent},
     icon::Icon,
     platform::ios::{ScreenEdge, ValidOrientations},
     platform_impl::platform::{
         app_state, monitor, EventLoopWindowTarget, Fullscreen, MonitorHandle,
     },
     window::{
-        CursorGrabMode, CursorIcon, ImePurpose, ResizeDirection, Theme, UserAttentionType,
-        WindowAttributes, WindowButtons, WindowId as RootWindowId, WindowLevel,
+        CursorGrabMode, CursorIcon, ImePurpose, NotSupportedError, ResizeDirection, Theme,
+        UserAttentionType, WindowAttributes, WindowButtons, WindowError, WindowId as RootWindowId,
+        WindowLevel,
     },
 };
 
@@ -174,28 +175,28 @@ impl Inner {
         debug!("`Window::set_cursor_icon` ignored on iOS")
     }
 
-    pub fn set_cursor_position(&self, _position: Position) -> Result<(), ExternalError> {
-        Err(ExternalError::NotSupported(NotSupportedError::new()))
+    pub fn set_cursor_position(&self, _position: Position) -> Result<(), WindowError> {
+        Err(WindowError::NotSupported(NotSupportedError::new()))
     }
 
-    pub fn set_cursor_grab(&self, _: CursorGrabMode) -> Result<(), ExternalError> {
-        Err(ExternalError::NotSupported(NotSupportedError::new()))
+    pub fn set_cursor_grab(&self, _: CursorGrabMode) -> Result<(), WindowError> {
+        Err(WindowError::NotSupported(NotSupportedError::new()))
     }
 
     pub fn set_cursor_visible(&self, _visible: bool) {
         debug!("`Window::set_cursor_visible` is ignored on iOS")
     }
 
-    pub fn drag_window(&self) -> Result<(), ExternalError> {
-        Err(ExternalError::NotSupported(NotSupportedError::new()))
+    pub fn drag_window(&self) -> Result<(), WindowError> {
+        Err(WindowError::NotSupported(NotSupportedError::new()))
     }
 
-    pub fn drag_resize_window(&self, _direction: ResizeDirection) -> Result<(), ExternalError> {
-        Err(ExternalError::NotSupported(NotSupportedError::new()))
+    pub fn drag_resize_window(&self, _direction: ResizeDirection) -> Result<(), WindowError> {
+        Err(WindowError::NotSupported(NotSupportedError::new()))
     }
 
-    pub fn set_cursor_hittest(&self, _hittest: bool) -> Result<(), ExternalError> {
-        Err(ExternalError::NotSupported(NotSupportedError::new()))
+    pub fn set_cursor_hittest(&self, _hittest: bool) -> Result<(), WindowError> {
+        Err(WindowError::NotSupported(NotSupportedError::new()))
     }
 
     pub fn set_minimized(&self, _minimized: bool) {

src/platform_impl/linux/mod.rs

@@ -14,11 +14,12 @@ use once_cell::sync::Lazy;
 use raw_window_handle::{RawDisplayHandle, RawWindowHandle};
 use smol_str::SmolStr;
 
+use crate::platform::startup_notify::ActivationTokenNotFound;
 #[cfg(x11_platform)]
 use crate::platform::x11::XlibErrorHook;
 use crate::{
     dpi::{PhysicalPosition, PhysicalSize, Position, Size},
-    error::{ExternalError, NotSupportedError, OsError as RootOsError},
+    error::OsError as RootOsError,
     event::{Event, KeyEvent},
     event_loop::{
         AsyncRequestSerial, ControlFlow, DeviceEvents, EventLoopClosed, EventLoopCreationError,
@@ -31,8 +32,9 @@ use crate::{
         scancode::KeyCodeExtScancode,
     },
     window::{
-        ActivationToken, CursorGrabMode, CursorIcon, ImePurpose, ResizeDirection, Theme,
-        UserAttentionType, WindowAttributes, WindowButtons, WindowLevel,
+        ActivationToken, CursorGrabMode, CursorIcon, ImePurpose, NotSupportedError,
+        ResizeDirection, Theme, UserAttentionType, WindowAttributes, WindowButtons, WindowError,
+        WindowLevel,
     },
 };
 #[cfg(x11_platform)]
@@ -375,7 +377,9 @@ impl Window {
     }
 
     #[inline]
-    pub(crate) fn request_activation_token(&self) -> Result<AsyncRequestSerial, NotSupportedError> {
+    pub(crate) fn request_activation_token(
+        &self,
+    ) -> Result<AsyncRequestSerial, ActivationTokenNotFound> {
         x11_or_wayland!(match self; Window(w) => w.request_activation_token())
     }
 
@@ -425,7 +429,7 @@ impl Window {
     }
 
     #[inline]
-    pub fn set_cursor_grab(&self, mode: CursorGrabMode) -> Result<(), ExternalError> {
+    pub fn set_cursor_grab(&self, mode: CursorGrabMode) -> Result<(), WindowError> {
         x11_or_wayland!(match self; Window(window) => window.set_cursor_grab(mode))
     }
 
@@ -435,17 +439,17 @@ impl Window {
     }
 
     #[inline]
-    pub fn drag_window(&self) -> Result<(), ExternalError> {
+    pub fn drag_window(&self) -> Result<(), WindowError> {
         x11_or_wayland!(match self; Window(window) => window.drag_window())
     }
 
     #[inline]
-    pub fn drag_resize_window(&self, direction: ResizeDirection) -> Result<(), ExternalError> {
+    pub fn drag_resize_window(&self, direction: ResizeDirection) -> Result<(), WindowError> {
         x11_or_wayland!(match self; Window(window) => window.drag_resize_window(direction))
     }
 
     #[inline]
-    pub fn set_cursor_hittest(&self, hittest: bool) -> Result<(), ExternalError> {
+    pub fn set_cursor_hittest(&self, hittest: bool) -> Result<(), WindowError> {
         x11_or_wayland!(match self; Window(w) => w.set_cursor_hittest(hittest))
     }
 
@@ -455,7 +459,7 @@ impl Window {
     }
 
     #[inline]
-    pub fn set_cursor_position(&self, position: Position) -> Result<(), ExternalError> {
+    pub fn set_cursor_position(&self, position: Position) -> Result<(), WindowError> {
         x11_or_wayland!(match self; Window(w) => w.set_cursor_position(position))
     }