fix: add cmp PartialEq to State

core/src/font.rs

@@ -1,5 +1,5 @@
 /// A font.
-#[derive(Debug, Clone, Copy, Default)]
+#[derive(Debug, Clone, Copy, Default, PartialEq)]
 pub enum Font {
     /// The default font.
     ///

graphics/src/primitive.rs

@@ -9,7 +9,7 @@ use crate::triangle;
 use std::sync::Arc;
 
 /// A rendering primitive.
-#[derive(Debug, Clone, Default)]
+#[derive(Debug, Clone, Default, PartialEq)]
 pub enum Primitive {
     /// An empty primitive
     #[default]

graphics/src/triangle.rs

@@ -2,7 +2,7 @@
 use bytemuck::{Pod, Zeroable};
 
 /// A set of [`Vertex2D`] and indices representing a list of triangles.
-#[derive(Clone, Debug)]
+#[derive(Clone, Debug, PartialEq)]
 pub struct Mesh2D<T> {
     /// The vertices of the mesh
     pub vertices: Vec<T>,
@@ -14,15 +14,15 @@ pub struct Mesh2D<T> {
 }
 
 /// A two-dimensional vertex.
-#[derive(Copy, Clone, Debug, Zeroable, Pod)]
+#[derive(Copy, Clone, Debug, Zeroable, Pod, PartialEq)]
 #[repr(C)]
 pub struct Vertex2D {
     /// The vertex position in 2D space.
     pub position: [f32; 2],
 }
 
 /// A two-dimensional vertex with a color.
-#[derive(Copy, Clone, Debug, Zeroable, Pod)]
+#[derive(Copy, Clone, Debug, Zeroable, Pod, PartialEq)]
 #[repr(C)]
 pub struct ColoredVertex2D {
     /// The vertex position in 2D space.

graphics/src/widget/canvas/cache.rs

@@ -4,7 +4,7 @@ use crate::Primitive;
 use iced_native::Size;
 use std::{cell::RefCell, sync::Arc};
 
-#[derive(Default)]
+#[derive(Default, PartialEq)]
 enum State {
     #[default]
     Empty,
@@ -18,7 +18,7 @@ enum State {
 ///
 /// A [`Cache`] will not redraw its geometry unless the dimensions of its layer
 /// change or it is explicitly cleared.
-#[derive(Debug, Default)]
+#[derive(Debug, Default, PartialEq)]
 pub struct Cache {
     state: RefCell<State>,
 }

graphics/src/widget/qr_code.rs

@@ -140,7 +140,7 @@ where
 /// The state of a [`QRCode`].
 ///
 /// It stores the data that will be displayed.
-#[derive(Debug)]
+#[derive(Debug, PartialEq)]
 pub struct State {
     contents: Vec<qrcode::Color>,
     width: usize,

lazy/src/responsive.rs

@@ -112,6 +112,7 @@ where
     }
 }
 
+#[derive(PartialEq)]
 struct State {
     tree: RefCell<Tree>,
 }

native/src/image.rs

@@ -6,7 +6,7 @@ use std::path::PathBuf;
 use std::sync::Arc;
 
 /// A handle of some image data.
-#[derive(Debug, Clone)]
+#[derive(Debug, Clone, PartialEq)]
 pub struct Handle {
     id: u64,
     data: Data,
@@ -91,6 +91,12 @@ impl Hash for Handle {
 #[derive(Clone)]
 pub struct Bytes(Arc<dyn AsRef<[u8]> + Send + Sync + 'static>);
 
+impl PartialEq for Bytes {
+    fn eq(&self, other: &Self) -> bool {
+        self.0.as_ref().as_ref() == other.0.as_ref().as_ref()
+    }
+}
+
 impl Bytes {
     /// Creates new [`Bytes`] around `data`.
     pub fn new(data: impl AsRef<[u8]> + Send + Sync + 'static) -> Self {
@@ -125,7 +131,7 @@ impl std::ops::Deref for Bytes {
 }
 
 /// The data of a raster image.
-#[derive(Clone, Hash)]
+#[derive(Clone, Hash, PartialEq)]
 pub enum Data {
     /// File data
     Path(PathBuf),

native/src/mouse/click.rs

@@ -3,15 +3,15 @@ use crate::time::Instant;
 use crate::Point;
 
 /// A mouse click.
-#[derive(Debug, Clone, Copy)]
+#[derive(Debug, Clone, Copy, PartialEq)]
 pub struct Click {
     kind: Kind,
     position: Point,
     time: Instant,
 }
 
 /// The kind of mouse click.
-#[derive(Debug, Clone, Copy)]
+#[derive(Debug, Clone, Copy, PartialEq)]
 pub enum Kind {
     /// A single click
     Single,

native/src/overlay/menu.rs

@@ -115,7 +115,7 @@ where
 }
 
 /// The local state of a [`Menu`].
-#[derive(Debug)]
+#[derive(Debug, PartialEq)]
 pub struct State {
     tree: Tree,
 }

native/src/svg.rs

@@ -7,7 +7,7 @@ use std::path::PathBuf;
 use std::sync::Arc;
 
 /// A handle of Svg data.
-#[derive(Debug, Clone)]
+#[derive(Debug, Clone, PartialEq)]
 pub struct Handle {
     id: u64,
     data: Arc<Data>,
@@ -57,7 +57,7 @@ impl Hash for Handle {
 }
 
 /// The data of a vectorial image.
-#[derive(Clone, Hash)]
+#[derive(Clone, Hash, PartialEq)]
 pub enum Data {
     /// File data
     Path(PathBuf),

native/src/widget/image/viewer.rs

@@ -336,7 +336,7 @@ where
 }
 
 /// The local state of a [`Viewer`].
-#[derive(Debug, Clone, Copy)]
+#[derive(Debug, Clone, Copy, PartialEq)]
 pub struct State {
     scale: f32,
     starting_offset: Vector,

native/src/widget/mouse_area.rs

@@ -68,7 +68,7 @@ impl<'a, Message, Renderer> MouseArea<'a, Message, Renderer> {
 }
 
 /// Local state of the [`MouseArea`].
-#[derive(Default)]
+#[derive(Default, PartialEq)]
 struct State {
     // TODO: Support on_mouse_enter and on_mouse_exit
 }

native/src/widget/scrollable.rs

@@ -947,7 +947,7 @@ fn notify_on_scroll<Message>(
 }
 
 /// The local state of a [`Scrollable`].
-#[derive(Debug, Clone, Copy)]
+#[derive(Debug, Clone, Copy, PartialEq)]
 pub struct State {
     scroll_area_touched_at: Option<Point>,
     offset_y: Offset,
@@ -982,7 +982,7 @@ impl operation::Scrollable for State {
     }
 }
 
-#[derive(Debug, Clone, Copy)]
+#[derive(Debug, Clone, Copy, PartialEq)]
 enum Offset {
     Absolute(f32),
     Relative(f32),
@@ -1002,7 +1002,7 @@ impl Offset {
 }
 
 /// The current [`Viewport`] of the [`Scrollable`].
-#[derive(Debug, Clone, Copy)]
+#[derive(Debug, Clone, Copy, PartialEq)]
 pub struct Viewport {
     offset_x: Offset,
     offset_y: Offset,

native/src/widget/text_input.rs

@@ -1134,7 +1134,7 @@ pub fn mouse_interaction(
 }
 
 /// The state of a [`TextInput`].
-#[derive(Debug, Default, Clone)]
+#[derive(Debug, Default, Clone, PartialEq)]
 pub struct State {
     is_focused: Option<Focus>,
     is_dragging: bool,
@@ -1145,7 +1145,7 @@ pub struct State {
     // TODO: Add stateful horizontal scrolling offset
 }
 
-#[derive(Debug, Clone, Copy)]
+#[derive(Debug, Clone, Copy, PartialEq)]
 struct Focus {
     updated_at: Instant,
     now: Instant,

native/src/widget/text_input/cursor.rs

@@ -2,13 +2,13 @@
 use crate::widget::text_input::Value;
 
 /// The cursor of a text input.
-#[derive(Debug, Copy, Clone)]
+#[derive(Debug, Copy, Clone, PartialEq)]
 pub struct Cursor {
     state: State,
 }
 
 /// The state of a [`Cursor`].
-#[derive(Debug, Copy, Clone)]
+#[derive(Debug, Copy, Clone, PartialEq)]
 pub enum State {
     /// Cursor without a selection
     Index(usize),

native/src/widget/text_input/value.rs

@@ -4,7 +4,7 @@ use unicode_segmentation::UnicodeSegmentation;
 ///
 /// [`TextInput`]: crate::widget::TextInput
 // TODO: Reduce allocations, cache results (?)
-#[derive(Debug, Clone)]
+#[derive(Debug, Clone, PartialEq)]
 pub struct Value {
     graphemes: Vec<String>,
 }

native/src/widget/tree.rs

@@ -8,7 +8,7 @@ use std::fmt;
 /// A persistent state widget tree.
 ///
 /// A [`Tree`] is normally associated with a specific widget in the widget tree.
-#[derive(Debug)]
+#[derive(Debug, PartialEq)]
 pub struct Tree {
     /// The tag of the [`Tree`].
     pub tag: Tag,
@@ -135,6 +135,18 @@ pub enum State {
     Some(Box<dyn Any>),
 }
 
+impl PartialEq for State {
+    fn eq(&self, other: &Self) -> bool {
+        match (self, other) {
+            (State::None, State::None) => true,
+            (State::Some(self_state), State::Some(other_state)) => {
+                self_state.downcast_ref::<Tree>() == other_state.downcast_ref::<Tree>()
+            }
+            _ => false,
+        }
+    }
+}
+
 impl State {
     /// Creates a new [`State`].
     pub fn new<T>(state: T) -> Self