Changed EventLoop to give a result instead of panicking

CHANGELOG.md

@@ -21,6 +21,7 @@ And please only add new entries to the top of this list, right below the `# Unre
 - **Breaking:** Replaced `EventLoopExtMacOS` with `EventLoopBuilderExtMacOS` (which also has renamed methods).
 - **Breaking:** Replaced `EventLoopExtWindows` with `EventLoopBuilderExtWindows` (which also has renamed methods).
 - **Breaking:** Replaced `EventLoopExtUnix` with `EventLoopBuilderExtUnix` (which also has renamed methods).
+- Changed to Results instead of a panic for creating a new EventLoop
 
 # 0.26.1 (2022-01-05)
 

examples/control_flow.rs

@@ -26,7 +26,7 @@ fn main() {
     println!("Press 'R' to toggle request_redraw() calls.");
     println!("Press 'Esc' to close the window.");
 
-    let event_loop = EventLoop::new();
+    let event_loop = EventLoop::new().unwrap();
     let window = WindowBuilder::new()
         .with_title("Press 1, 2, 3 to change control flow mode. Press R to toggle redraw requests.")
         .build(&event_loop)

examples/cursor.rs

@@ -7,7 +7,7 @@ use winit::{
 
 fn main() {
     SimpleLogger::new().init().unwrap();
-    let event_loop = EventLoop::new();
+    let event_loop = EventLoop::new().unwrap();
 
     let window = WindowBuilder::new().build(&event_loop).unwrap();
     window.set_title("A fantastic window!");

examples/cursor_grab.rs

@@ -7,7 +7,7 @@ use winit::{
 
 fn main() {
     SimpleLogger::new().init().unwrap();
-    let event_loop = EventLoop::new();
+    let event_loop = EventLoop::new().unwrap();
 
     let window = WindowBuilder::new()
         .with_title("Super Cursor Grab'n'Hide Simulator 9000")

examples/custom_events.rs

@@ -13,7 +13,8 @@ fn main() {
     }
 
     SimpleLogger::new().init().unwrap();
-    let event_loop = EventLoopBuilder::<CustomEvent>::with_user_event().build();
+
+    let event_loop = EventLoopBuilder::<CustomEvent>::with_user_event().build().unwrap();
 
     let _window = WindowBuilder::new()
         .with_title("A fantastic window!")

examples/drag_window.rs

@@ -9,7 +9,7 @@ use winit::{
 
 fn main() {
     SimpleLogger::new().init().unwrap();
-    let event_loop = EventLoop::new();
+    let event_loop = EventLoop::new().unwrap();
 
     let window_1 = WindowBuilder::new().build(&event_loop).unwrap();
     let window_2 = WindowBuilder::new().build(&event_loop).unwrap();

examples/fullscreen.rs

@@ -8,7 +8,7 @@ use winit::window::{Fullscreen, WindowBuilder};
 
 fn main() {
     SimpleLogger::new().init().unwrap();
-    let event_loop = EventLoop::new();
+    let event_loop = EventLoop::new().unwrap();
 
     print!("Please choose the fullscreen mode: (1) exclusive, (2) borderless: ");
     stdout().flush().unwrap();

examples/handling_close.rs

@@ -7,7 +7,7 @@ use winit::{
 
 fn main() {
     SimpleLogger::new().init().unwrap();
-    let event_loop = EventLoop::new();
+    let event_loop = EventLoop::new().unwrap();
 
     let _window = WindowBuilder::new()
         .with_title("Your faithful window")

examples/min_max_size.rs

@@ -8,7 +8,7 @@ use winit::{
 
 fn main() {
     SimpleLogger::new().init().unwrap();
-    let event_loop = EventLoop::new();
+    let event_loop = EventLoop::new().unwrap();
 
     let window = WindowBuilder::new().build(&event_loop).unwrap();
 

examples/minimize.rs

@@ -7,7 +7,7 @@ use winit::window::WindowBuilder;
 
 fn main() {
     SimpleLogger::new().init().unwrap();
-    let event_loop = EventLoop::new();
+    let event_loop = EventLoop::new().unwrap();
 
     let window = WindowBuilder::new()
         .with_title("A fantastic window!")

examples/monitor_list.rs

@@ -3,7 +3,7 @@ use winit::{event_loop::EventLoop, window::WindowBuilder};
 
 fn main() {
     SimpleLogger::new().init().unwrap();
-    let event_loop = EventLoop::new();
+    let event_loop = EventLoop::new().unwrap();
     let window = WindowBuilder::new().build(&event_loop).unwrap();
 
     dbg!(window.available_monitors().collect::<Vec<_>>());

examples/mouse_wheel.rs

@@ -7,7 +7,7 @@ use winit::{
 
 fn main() {
     SimpleLogger::new().init().unwrap();
-    let event_loop = EventLoop::new();
+    let event_loop = EventLoop::new().unwrap();
 
     let window = WindowBuilder::new()
         .with_title("Mouse Wheel events")

examples/multithreaded.rs

@@ -14,7 +14,7 @@ fn main() {
     const WINDOW_SIZE: PhysicalSize<u32> = PhysicalSize::new(600, 400);
 
     SimpleLogger::new().init().unwrap();
-    let event_loop = EventLoop::new();
+    let event_loop = EventLoop::new().unwrap();
     let mut window_senders = HashMap::with_capacity(WINDOW_COUNT);
     for _ in 0..WINDOW_COUNT {
         let window = WindowBuilder::new()

examples/multiwindow.rs

@@ -9,7 +9,7 @@ use winit::{
 
 fn main() {
     SimpleLogger::new().init().unwrap();
-    let event_loop = EventLoop::new();
+    let event_loop = EventLoop::new().unwrap();
 
     let mut windows = HashMap::new();
     for _ in 0..3 {

examples/request_redraw.rs

@@ -7,7 +7,7 @@ use winit::{
 
 fn main() {
     SimpleLogger::new().init().unwrap();
-    let event_loop = EventLoop::new();
+    let event_loop = EventLoop::new().unwrap();
 
     let window = WindowBuilder::new()
         .with_title("A fantastic window!")

examples/request_redraw_threaded.rs

@@ -10,7 +10,7 @@ fn main() {
     };
 
     SimpleLogger::new().init().unwrap();
-    let event_loop = EventLoop::new();
+    let event_loop = EventLoop::new().unwrap();
 
     let window = WindowBuilder::new()
         .with_title("A fantastic window!")

examples/resizable.rs

@@ -8,7 +8,7 @@ use winit::{
 
 fn main() {
     SimpleLogger::new().init().unwrap();
-    let event_loop = EventLoop::new();
+    let event_loop = EventLoop::new().unwrap();
 
     let mut resizable = false;
 

examples/set_ime_position.rs

@@ -8,7 +8,7 @@ use winit::{
 
 fn main() {
     SimpleLogger::new().init().unwrap();
-    let event_loop = EventLoop::new();
+    let event_loop = EventLoop::new().unwrap();
 
     let window = WindowBuilder::new().build(&event_loop).unwrap();
     window.set_title("A fantastic window!");

examples/timer.rs

@@ -10,7 +10,7 @@ use winit::{
 
 fn main() {
     SimpleLogger::new().init().unwrap();
-    let event_loop = EventLoop::new();
+    let event_loop = EventLoop::new().unwrap();
 
     let _window = WindowBuilder::new()
         .with_title("A fantastic window!")

examples/transparent.rs

@@ -7,7 +7,7 @@ use winit::{
 
 fn main() {
     SimpleLogger::new().init().unwrap();
-    let event_loop = EventLoop::new();
+    let event_loop = EventLoop::new().unwrap();
 
     let window = WindowBuilder::new()
         .with_decorations(false)

examples/video_modes.rs

@@ -3,7 +3,7 @@ use winit::event_loop::EventLoop;
 
 fn main() {
     SimpleLogger::new().init().unwrap();
-    let event_loop = EventLoop::new();
+    let event_loop = EventLoop::new().unwrap();
     let monitor = match event_loop.primary_monitor() {
         Some(monitor) => monitor,
         None => {

examples/web.rs

@@ -5,7 +5,7 @@ use winit::{
 };
 
 pub fn main() {
-    let event_loop = EventLoop::new();
+    let event_loop = EventLoop::new().unwrap();
 
     let window = WindowBuilder::new()
         .with_title("A fantastic window!")

examples/window.rs

@@ -7,7 +7,7 @@ use winit::{
 
 fn main() {
     SimpleLogger::new().init().unwrap();
-    let event_loop = EventLoop::new();
+    let event_loop = EventLoop::new().unwrap();
 
     let window = WindowBuilder::new()
         .with_title("A fantastic window!")

examples/window_debug.rs

@@ -10,7 +10,7 @@ use winit::{
 
 fn main() {
     SimpleLogger::new().init().unwrap();
-    let event_loop = EventLoop::new();
+    let event_loop = EventLoop::new().unwrap();
 
     let window = WindowBuilder::new()
         .with_title("A fantastic window!")

examples/window_icon.rs

@@ -19,7 +19,7 @@ fn main() {
 
     let icon = load_icon(Path::new(path));
 
-    let event_loop = EventLoop::new();
+    let event_loop = EventLoop::new().unwrap();
 
     let window = WindowBuilder::new()
         .with_title("An iconic window!")

examples/window_run_return.rs

@@ -18,7 +18,7 @@ fn main() {
         platform::run_return::EventLoopExtRunReturn,
         window::WindowBuilder,
     };
-    let mut event_loop = EventLoop::new();
+    let mut event_loop = EventLoop::new().unwrap();
 
     SimpleLogger::new().init().unwrap();
     let _window = WindowBuilder::new()

src/event_loop.rs

@@ -93,11 +93,14 @@ impl<T> EventLoopBuilder<T> {
     ///
     /// - **iOS:** Can only be called on the main thread.
     #[inline]
-    pub fn build(&mut self) -> EventLoop<T> {
-        EventLoop {
-            event_loop: platform_impl::EventLoop::new(&self.platform_specific),
+    pub fn build(&mut self) -> Result<EventLoop<T>, String> {
+        Ok(EventLoop {
+            event_loop: match platform_impl::EventLoop::new(&self.platform_specific) {
+                Ok(event_loop) => event_loop,
+                Err(err) => return Err(format!("Error creating event loop: {}", err)),
+            },
             _marker: PhantomData,
-        }
+        })
     }
 }
 
@@ -177,14 +180,14 @@ impl Default for ControlFlow {
 impl EventLoop<()> {
     /// Alias for `EventLoopBuilder::new().build()`.
     #[inline]
-    pub fn new() -> EventLoop<()> {
+    pub fn new() -> Result<EventLoop<()>, String> {
         EventLoopBuilder::new().build()
     }
 }
 
 impl<T> EventLoop<T> {
     #[deprecated = "Use `EventLoopBuilder::<T>::with_user_event().build()` instead."]
-    pub fn with_user_event() -> EventLoop<T> {
+    pub fn with_user_event() -> Result<EventLoop<T>, String> {
         EventLoopBuilder::<T>::with_user_event().build()
     }
 

src/lib.rs

@@ -7,7 +7,7 @@
 //!
 //! ```no_run
 //! use winit::event_loop::EventLoop;
-//! let event_loop = EventLoop::new();
+//! let event_loop = EventLoop::new().unwrap();
 //! ```
 //!
 //! Once this is done there are two ways to create a [`Window`]:
@@ -48,7 +48,7 @@
 //!     window::WindowBuilder,
 //! };
 //!
-//! let event_loop = EventLoop::new();
+//! let event_loop = EventLoop::new().unwrap();
 //! let window = WindowBuilder::new().build(&event_loop).unwrap();
 //!
 //! event_loop.run(move |event, _, control_flow| {

src/platform_impl/linux/mod.rs

@@ -606,45 +606,51 @@ impl<T: 'static> Clone for EventLoopProxy<T> {
 }
 
 impl<T: 'static> EventLoop<T> {
-    pub(crate) fn new(attributes: &PlatformSpecificEventLoopAttributes) -> Self {
+    pub(crate) fn new(attributes: &PlatformSpecificEventLoopAttributes) -> Result<Self, String> {
         if !attributes.any_thread && !is_main_thread() {
-            panic!(
+            return Err(
                 "Initializing the event loop outside of the main thread is a significant \
                  cross-platform compatibility hazard. If you absolutely need to create an \
                  EventLoop on a different thread, you can use the \
-                 `EventLoopBuilderExtUnix::any_thread` function."
+                 `EventLoopBuilderExtUnix::any_thread` function.".to_string()
             );
         }
 
         #[cfg(feature = "x11")]
         if attributes.forced_backend == Some(Backend::X) {
             // TODO: Propagate
-            return EventLoop::new_x11_any_thread().unwrap();
+            return Ok(EventLoop::new_x11_any_thread().unwrap());
         }
 
         #[cfg(feature = "wayland")]
         if attributes.forced_backend == Some(Backend::Wayland) {
             // TODO: Propagate
-            return EventLoop::new_wayland_any_thread().expect("failed to open Wayland connection");
+            return Ok(EventLoop::new_wayland_any_thread().expect("failed to open Wayland connection"));
         }
 
         if let Ok(env_var) = env::var(BACKEND_PREFERENCE_ENV_VAR) {
             match env_var.as_str() {
                 "x11" => {
                     // TODO: propagate
                     #[cfg(feature = "x11")]
-                    return EventLoop::new_x11_any_thread()
-                        .expect("Failed to initialize X11 backend");
+                    return match EventLoop::new_x11_any_thread() {
+                        Ok(event_loop) => Ok(event_loop),
+                        Err(e) => Err(format!("Failed to initialize X11 Backend: {}", e)),
+                    };
+
                     #[cfg(not(feature = "x11"))]
-                    panic!("x11 feature is not enabled")
+                    Err("x11 feature is not enabled")
                 }
                 "wayland" => {
                     #[cfg(feature = "wayland")]
-                    return EventLoop::new_wayland_any_thread()
-                        .expect("Failed to initialize Wayland backend");
+                    return match EventLoop::new_wayland_any_thread() {
+                        Ok(event_loop) => Ok(event_loop),
+                        Err(e) => Err(format!("Failed to initialize Wayland Backend: {}", e)),
+                    };
                     #[cfg(not(feature = "wayland"))]
-                    panic!("wayland feature is not enabled");
+                    Err("wayland feature is not enabled");
                 }
+                // I don't know what to convert this to for the Result, so I'll keep it for now
                 _ => panic!(
                     "Unknown environment variable value for {}, try one of `x11`,`wayland`",
                     BACKEND_PREFERENCE_ENV_VAR,
@@ -654,13 +660,13 @@ impl<T: 'static> EventLoop<T> {
 
         #[cfg(feature = "wayland")]
         let wayland_err = match EventLoop::new_wayland_any_thread() {
-            Ok(event_loop) => return event_loop,
+            Ok(event_loop) => return Ok(event_loop),
             Err(err) => err,
         };
 
         #[cfg(feature = "x11")]
         let x11_err = match EventLoop::new_x11_any_thread() {
-            Ok(event_loop) => return event_loop,
+            Ok(event_loop) => return Ok(event_loop),
             Err(err) => err,
         };