Implement `Hash` on some enums in `backend::input`

CHANGELOG.md

@@ -28,6 +28,7 @@
 #### Backends
 
 - `x11rb` event source integration used in anvil's XWayland implementation is now part of smithay at `utils::x11rb`. Enabled through the `x11rb_event_source` feature. 
+- `KeyState`, `MouseButton`, `ButtonState` and `Axis` in `backend::input` now derive `Hash`.
 - New `DrmNode` type in drm backend. This is primarily for use a backend which needs to run as client inside another session.
 
 ### Bugfixes

src/backend/input/mod.rs

@@ -77,7 +77,7 @@ impl<B: InputBackend> Event<B> for UnusedEvent {
 }
 
 /// State of key on a keyboard. Either pressed or released
-#[derive(Debug, PartialEq, Eq, Clone, Copy)]
+#[derive(Debug, PartialEq, Eq, Clone, Copy, Hash)]
 pub enum KeyState {
     /// Key is released
     Released,
@@ -110,7 +110,7 @@ impl<B: InputBackend> KeyboardKeyEvent<B> for UnusedEvent {
 }
 
 /// A particular mouse button
-#[derive(Debug, PartialEq, Eq, Clone, Copy)]
+#[derive(Debug, PartialEq, Eq, Clone, Copy, Hash)]
 pub enum MouseButton {
     /// Left mouse button
     Left,
@@ -123,7 +123,7 @@ pub enum MouseButton {
 }
 
 /// State of a button on a pointer device, like mouse or tablet tool. Either pressed or released
-#[derive(Debug, PartialEq, Eq, Clone, Copy)]
+#[derive(Debug, PartialEq, Eq, Clone, Copy, Hash)]
 pub enum ButtonState {
     /// Button is released
     Released,
@@ -150,7 +150,7 @@ impl<B: InputBackend> PointerButtonEvent<B> for UnusedEvent {
 }
 
 /// Axis when scrolling
-#[derive(Debug, PartialEq, Eq, Clone, Copy)]
+#[derive(Debug, PartialEq, Eq, Clone, Copy, Hash)]
 pub enum Axis {
     /// Vertical axis
     Vertical,