Remove support for stdweb (#1941)

* Remove support for `stdweb`

* Expunge `stdweb`; make `web-sys` the default

* Mark this change as a breaking change

* Re-insert accidental removal of space

* Use the correct cargo feature syntax

* Re-add some `cfg` attributes

* Remove `web-sys` feature from CI

.github/workflows/ci.yml

@@ -45,8 +45,7 @@ jobs:
           - { target: aarch64-apple-ios,        os: macos-latest,    }
           # We're using Windows rather than Ubuntu to run the wasm tests because caching cargo-web
           # doesn't currently work on Linux.
-          - { target: wasm32-unknown-unknown,   os: windows-latest, features: stdweb,  cmd: web }
-          - { target: wasm32-unknown-unknown,   os: windows-latest, features: web-sys, cmd: web }
+          - { target: wasm32-unknown-unknown,   os: windows-latest, cmd: web }
 
     env:
       RUST_BACKTRACE: 1

CHANGELOG.md

@@ -1,5 +1,6 @@
 # Unreleased
 
+- **Breaking:** On Web, remove the `stdweb` backend.
 - Added `Window::focus_window`to bring the window to the front and set input focus.
 
 # 0.25.0 (2021-05-15)

Cargo.toml

@@ -12,19 +12,17 @@ documentation = "https://docs.rs/winit"
 categories = ["gui"]
 
 [package.metadata.docs.rs]
-features = ["serde", "web-sys"]
+features = ["serde"]
 default-target = "x86_64-unknown-linux-gnu"
 targets = ["i686-pc-windows-msvc", "x86_64-pc-windows-msvc", "i686-unknown-linux-gnu", "x86_64-unknown-linux-gnu", "x86_64-apple-darwin", "wasm32-unknown-unknown"]
 
 [features]
 default = ["x11", "wayland"]
-web-sys = ["web_sys", "wasm-bindgen", "instant/wasm-bindgen"]
-stdweb = ["std_web", "instant/stdweb"]
 x11 = ["x11-dl", "mio", "mio-misc", "percent-encoding", "parking_lot"]
 wayland = ["wayland-client", "sctk"]
 
 [dependencies]
-instant = "0.1"
+instant = { version = "0.1", features = ["wasm-bindgen"] }
 lazy_static = "1"
 libc = "0.2.64"
 log = "0.4"
@@ -97,7 +95,6 @@ parking_lot = { version = "0.11.0", optional = true }
 [target.'cfg(target_arch = "wasm32")'.dependencies.web_sys]
 package = "web-sys"
 version = "0.3.22"
-optional = true
 features = [
     'console',
     "AddEventListenerOptions",
@@ -123,13 +120,6 @@ features = [
 
 [target.'cfg(target_arch = "wasm32")'.dependencies.wasm-bindgen]
 version = "0.2.45"
-optional = true
-
-[target.'cfg(target_arch = "wasm32")'.dependencies.std_web]
-package = "stdweb"
-version = "=0.4.20"
-optional = true
-features = ["experimental_features_which_may_break_on_minor_version_bumps"]
 
 [target.'cfg(target_arch = "wasm32")'.dev-dependencies]
 console_log = "0.2"

FEATURES.md

@@ -183,11 +183,9 @@ Legend:
 |Fullscreen                       |✔️     |✔️     |✔️         |✔️             |**N/A**|✔️     |✔️        |
 |Fullscreen toggle                |✔️     |✔️     |✔️         |✔️             |**N/A**|✔️     |✔️        |
 |Exclusive fullscreen             |✔️     |✔️     |✔️         |**N/A**         |❌    |✔️     |**N/A**|
-|HiDPI support                    |✔️     |✔️     |✔️         |✔️             |▢[#721]|✔️    |✔️ \*1|
+|HiDPI support                    |✔️     |✔️     |✔️         |✔️             |▢[#721]|✔️    |✔️    |
 |Popup windows                    |❌     |❌     |❌         |❌             |❌    |❌     |**N/A**|
 
-\*1: `WindowEvent::ScaleFactorChanged` is not sent on `stdweb` backend.
-
 ### System information
 |Feature          |Windows|MacOS |Linux x11|Linux Wayland|Android|iOS      |WASM      |
 |---------------- | ----- | ---- | ------- | ----------- | ----- | ------- | -------- |

README.md

@@ -72,10 +72,7 @@ Winit provides the following features, which can be enabled in your `Cargo.toml`
 
 #### WebAssembly
 
-Winit supports compiling to the `wasm32-unknown-unknown` target with either a
-`stdweb` or a `web-sys` backend for use on web browsers. However, please note
-that **the `stdweb` backend is being deprecated and may be removed in a future
-release of Winit**. The `web-sys` backend is also more feature complete.
+Winit supports compiling to the `wasm32-unknown-unknown` target with `web-sys`.
 
 On the web platform, a Winit window is backed by a `<canvas>` element. You can
 either [provide Winit with a `<canvas>` element][web with_canvas], or [let Winit

examples/web.rs

@@ -12,7 +12,7 @@ pub fn main() {
         .build(&event_loop)
         .unwrap();
 
-    #[cfg(feature = "web-sys")]
+    #[cfg(target_arch = "wasm32")]
     {
         use winit::platform::web::WindowExtWebSys;
 
@@ -26,28 +26,12 @@ pub fn main() {
             .expect("Append canvas to HTML body");
     }
 
-    #[cfg(feature = "stdweb")]
-    {
-        use std_web::web::INode;
-        use winit::platform::web::WindowExtStdweb;
-
-        let canvas = window.canvas();
-
-        let document = std_web::web::document();
-        let body: std_web::web::Node = document.body().expect("Get HTML body").into();
-
-        body.append_child(&canvas);
-    }
-
     event_loop.run(move |event, _, control_flow| {
         *control_flow = ControlFlow::Wait;
 
-        #[cfg(feature = "web-sys")]
+        #[cfg(target_arch = "wasm32")]
         log::debug!("{:?}", event);
 
-        #[cfg(feature = "stdweb")]
-        std_web::console!(log, "%s", format!("{:?}", event));
-
         match event {
             Event::WindowEvent {
                 event: WindowEvent::CloseRequested,
@@ -61,7 +45,7 @@ pub fn main() {
     });
 }
 
-#[cfg(feature = "web-sys")]
+#[cfg(target_arch = "wasm32")]
 mod wasm {
     use wasm_bindgen::prelude::*;
 

src/lib.rs

@@ -146,8 +146,6 @@ extern crate bitflags;
 #[cfg(any(target_os = "macos", target_os = "ios"))]
 #[macro_use]
 extern crate objc;
-#[cfg(all(target_arch = "wasm32", feature = "std_web"))]
-extern crate std_web as stdweb;
 
 pub mod dpi;
 #[macro_use]

src/platform/web.rs

@@ -1,55 +1,25 @@
 #![cfg(target_arch = "wasm32")]
 
 //! The web target does not automatically insert the canvas element object into the web page, to
-//! allow end users to determine how the page should be laid out. Use the `WindowExtStdweb` or
-//! `WindowExtWebSys` traits (depending on your web backend) to retrieve the canvas from the
-//! Window. Alternatively, use the `WindowBuilderExtStdweb` or `WindowBuilderExtWebSys` to provide
-//! your own canvas.
+//! allow end users to determine how the page should be laid out. Use the `WindowExtWebSys` trait
+//! to retrieve the canvas from the Window. Alternatively, use the `WindowBuilderExtWebSys` trait
+//! to provide your own canvas.
 
 use crate::window::WindowBuilder;
 
-#[cfg(feature = "stdweb")]
-use stdweb::web::html_element::CanvasElement;
-
-#[cfg(feature = "stdweb")]
-pub trait WindowExtStdweb {
-    fn canvas(&self) -> CanvasElement;
-
-    /// Whether the browser reports the preferred color scheme to be "dark".
-    fn is_dark_mode(&self) -> bool;
-}
-
-#[cfg(feature = "web-sys")]
 use web_sys::HtmlCanvasElement;
 
-#[cfg(feature = "web-sys")]
 pub trait WindowExtWebSys {
     fn canvas(&self) -> HtmlCanvasElement;
 
     /// Whether the browser reports the preferred color scheme to be "dark".
     fn is_dark_mode(&self) -> bool;
 }
 
-#[cfg(feature = "stdweb")]
-pub trait WindowBuilderExtStdweb {
-    fn with_canvas(self, canvas: Option<CanvasElement>) -> Self;
-}
-
-#[cfg(feature = "stdweb")]
-impl WindowBuilderExtStdweb for WindowBuilder {
-    fn with_canvas(mut self, canvas: Option<CanvasElement>) -> Self {
-        self.platform_specific.canvas = canvas;
-
-        self
-    }
-}
-
-#[cfg(feature = "web-sys")]
 pub trait WindowBuilderExtWebSys {
     fn with_canvas(self, canvas: Option<HtmlCanvasElement>) -> Self;
 }
 
-#[cfg(feature = "web-sys")]
 impl WindowBuilderExtWebSys for WindowBuilder {
     fn with_canvas(mut self, canvas: Option<HtmlCanvasElement>) -> Self {
         self.platform_specific.canvas = canvas;

src/platform_impl/web/mod.rs

@@ -1,5 +1,5 @@
 // Brief introduction to the internals of the web backend:
-// Currently, the web backend supports both wasm-bindgen and stdweb as methods of binding to the
+// The web backend used to support both wasm-bindgen and stdweb as methods of binding to the
 // environment. Because they are both supporting the same underlying APIs, the actual web bindings
 // are cordoned off into backend abstractions, which present the thinnest unifying layer possible.
 //
@@ -17,26 +17,15 @@
 // incoming events (from the registered handlers) and ensuring they are passed to the user in a
 // compliant way.
 
-// Silence warnings from use of deprecated stdweb backend
-#![allow(deprecated)]
-
 mod device;
 mod error;
 mod event_loop;
 mod monitor;
 mod window;
 
-#[cfg(feature = "web-sys")]
 #[path = "web_sys/mod.rs"]
 mod backend;
 
-#[cfg(feature = "stdweb")]
-#[path = "stdweb/mod.rs"]
-mod backend;
-
-#[cfg(not(any(feature = "web-sys", feature = "stdweb")))]
-compile_error!("Please select a feature to build for web: `web-sys`, `stdweb`");
-
 pub use self::device::Id as DeviceId;
 pub use self::error::OsError;
 pub use self::event_loop::{