From 51350b7af188667e1337917405470d067021636b Mon Sep 17 00:00:00 2001
From: Andreas Reich <r_andreas2@web.de>
Date: Wed, 31 Jan 2024 09:52:20 +0100
Subject: [PATCH] Update docs for `Backend` and implement `std::fmt::Display`

---
 CHANGELOG.md          |  2 +-
 tests/src/image.rs    |  2 +-
 wgpu-types/src/lib.rs | 12 +++++++++---
 3 files changed, 11 insertions(+), 5 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 99bbcbc48b6..43d1250fa54 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -94,7 +94,7 @@ Bottom level categories:
   - As with other instance flags, this flag can be changed in calls to `InstanceFlags::with_env` with the new `WGPU_GPU_BASED_VALIDATION` environment variable.
 
   By @ErichDonGubler in [#5046](https://github.com/gfx-rs/wgpu/pull/5046).
-
+- `wgpu::Backend` now implements `std::fmt::Display` instead of providing a `to_str` method
 
 ### Bug Fixes
 
diff --git a/tests/src/image.rs b/tests/src/image.rs
index 4c1f6b8b740..c80edb955d2 100644
--- a/tests/src/image.rs
+++ b/tests/src/image.rs
@@ -183,7 +183,7 @@ pub async fn compare_image_output(
     let file_stem = reference_path.file_stem().unwrap().to_string_lossy();
     let renderer = format!(
         "{}-{}-{}",
-        adapter_info.backend.to_str(),
+        adapter_info.backend,
         sanitize_for_path(&adapter_info.name),
         sanitize_for_path(&adapter_info.driver)
     );
diff --git a/wgpu-types/src/lib.rs b/wgpu-types/src/lib.rs
index 34a7f130ff4..4ac30205db2 100644
--- a/wgpu-types/src/lib.rs
+++ b/wgpu-types/src/lib.rs
@@ -98,13 +98,13 @@ pub const QUERY_SIZE: u32 = 8;
 pub enum Backend {
     /// Dummy backend, used for testing.
     Empty = 0,
-    /// Vulkan API
+    /// Vulkan API (Windows, Linux, Android, MacOS via `vulkan-portability`/MoltenVK)
     Vulkan = 1,
     /// Metal API (Apple platforms)
     Metal = 2,
     /// Direct3D-12 (Windows)
     Dx12 = 3,
-    /// OpenGL ES-3 (Linux, Android)
+    /// OpenGL ES-3 (Linux, Android, WebGL, Windows, MacOS via Angle)
     Gl = 4,
     /// WebGPU in the browser
     BrowserWebGpu = 5,
@@ -112,7 +112,7 @@ pub enum Backend {
 
 impl Backend {
     /// Returns the string name of the backend.
-    pub fn to_str(self) -> &'static str {
+    pub const fn to_str(self) -> &'static str {
         match self {
             Backend::Empty => "empty",
             Backend::Vulkan => "vulkan",
@@ -124,6 +124,12 @@ impl Backend {
     }
 }
 
+impl std::fmt::Display for Backend {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        f.write_str(self.to_str())
+    }
+}
+
 /// Power Preference when choosing a physical adapter.
 ///
 /// Corresponds to [WebGPU `GPUPowerPreference`](