Fix raw window handle pub

[serpilliere]

If an end user wants to use raw handles, the trait must be defined as public to be included in external projects.

[Cobrand]

I don't understand how this is necessary? If you add raw-window-handle in your external project's Cargo.toml, it will use the same version if it's compatible, and you should be able to use the traits normally then, should you not?

[serpilliere]

Hi @Cobrand
Maybe I am missing something, but your trait is not exported as public (like, for example, a structure declaration in a crate which is not tagged as pub). So code that uses this crate are not allowed to use it.
In this case, if I create a simple rust projet with this cargo:

[package]
name = "test_sdl2_raw"
version = "0.1.0"
edition = "2021"

[dependencies]
sdl2 = {version = "0.35.0", features = ["bundled", "raw-window-handle"]}

And with this code:

use sdl2::raw_window_handle::RawWindowHandle;

fn main() {
    println!("Hello, world!");
}

I have this result:

$ cargo build --release
   Compiling test_sdl2_raw v0.1.0 (/home/serpilliere/projet/test_rust/test_sdl2_raw)
error[E0603]: enum `RawWindowHandle` is private
  --> src/main.rs:1:30
   |
1  | use sdl2::raw_window_handle::RawWindowHandle;
   |                              ^^^^^^^^^^^^^^^ private enum
   |
note: the enum `RawWindowHandle` is defined here
  --> /home/serpilliere/.cargo/registry/src/index.crates.io-6f17d22bba15001f/sdl2-0.35.2/src/sdl2/raw_window_handle.rs:3:51
   |
3  | use self::raw_window_handle::{HasRawWindowHandle, RawWindowHandle};
   |                                                   ^^^^^^^^^^^^^^^

So I won't be able to use functions associated to this trait. (so no raw handles)

[Cobrand]

[dependencies]
sdl2 = {version = "0.35.0", features = ["bundled", "raw-window-handle"]}
raw-window-handle = "0.5"

then

use raw_window_handle::RawWindowHandle;

doesn't this work?

You are rarely supposed to use raw-window-handle by yourself anyway, it almost always interops with something else (OpenGL, vulkan, DirectX, ...), which almost imports raw-window-handle, so I don't see why it would be our job to re-export this trait.

[serpilliere]

Nop: it doesn't work and I don't really understand why.

Cargo.toml:

[package]
name = "test_sdl2_raw"
version = "0.1.0"
edition = "2021"

# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html

[dependencies]
sdl2 = {version = "0.35.0", features = ["bundled", "raw-window-handle"]}
raw-window-handle = "0.5"

And the source:

use raw_window_handle::RawWindowHandle;
use raw_window_handle::HasRawWindowHandle;

fn main() {
    let sdl = sdl2::init().expect("xx");

    let video_subsystem = sdl
        .video().expect("xx");

    let clipboard = video_subsystem.clipboard();

    let gl_attr = video_subsystem.gl_attr();

    let mut builder =
        sdl2::video::WindowBuilder::new(&video_subsystem, "test", 800, 600);
    let builder = builder.opengl().allow_highdpi();
    let window = builder.build().expect("Cannot build window");
    if let RawWindowHandle::Xlib(handle) = window.raw_window_handle() {
        println!("Raw handle {:?}", handle);
    }
}

I have the following error:

$ cargo run --release
   Compiling test_sdl2_raw v0.1.0 (/home/serpilliere/projet/test_rust/test_sdl2_raw)
error[E0599]: no method named `raw_window_handle` found for struct `sdl2::video::Window` in the current scope
  --> src/main.rs:18:51
   |
18 |     if let RawWindowHandle::Xlib(handle) = window.raw_window_handle() {
   |                                                   ^^^^^^^^^^^^^^^^^ method not found in `Window`
   |
  ::: /home/serpilliere/.cargo/registry/src/index.crates.io-6f17d22bba15001f/raw-window-handle-0.4.3/src/lib.rs:58:8
   |
58 |     fn raw_window_handle(&self) -> RawWindowHandle;
   |        ----------------- the method is available for `sdl2::video::Window` here
   |
   = help: items from traits can only be used if the trait is in scope
help: the following trait is implemented but not in scope; perhaps add a `use` for it:
   |
1  + use raw_window_handle::HasRawWindowHandle;
   |

warning: unused import: `raw_window_handle::HasRawWindowHandle`
 --> src/main.rs:2:5
  |
2 | use raw_window_handle::HasRawWindowHandle;
  |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  |
  = note: `#[warn(unused_imports)]` on by default

For more information about this error, try `rustc --explain E0599`.
warning: `test_sdl2_raw` (bin "test_sdl2_raw") generated 1 warning
error: could not compile `test_sdl2_raw` (bin "test_sdl2_raw") due to previous error; 1 warning emitted

What is interesting is that the compiler:

• first says that the import is useless
• that we need to import the trait

It make me thinks that it's a bit like the same error when you have a version of crate used in a sub module and you use the same crate but with a different version. The compiler doesn't mix those object.

Have you got an example of a code which uses raw handles from a program outside of the crate sdl2 itself?

[Cobrand]

You are using rust-sdl2 0.35.0, which uses a different version of raw-window-handle. Try updating to rust-sdl2 0.36, or downgrading raw-window-handle.

[serpilliere]

Oh!
You are right. I missed the update.
Sorry for this @Cobrand