fix: missing canvas property on Context2D (#597)

__test__/canvas-class.spec.ts

@@ -5,3 +5,9 @@ import { createCanvas, Canvas } from '../index'
 test('Canvas constructor should be equal to createCanvas', (t) => {
   t.true(new Canvas(100, 100) instanceof createCanvas(100, 100).constructor)
 })
+
+test('ctx.canvas should be equal to canvas', (t) => {
+  const canvas = createCanvas(100, 100)
+  const ctx = canvas.getContext('2d')
+  t.is(ctx.canvas, canvas)
+})

index.d.ts

@@ -248,8 +248,9 @@ export interface StrokeOptions {
 export interface SKRSContext2D
   extends Omit<
     CanvasRenderingContext2D,
-    'drawImage' | 'createPattern' | 'getTransform' | 'drawFocusIfNeeded' | 'scrollPathIntoView'
+    'drawImage' | 'createPattern' | 'getTransform' | 'drawFocusIfNeeded' | 'scrollPathIntoView' | 'canvas'
   > {
+  canvas: Canvas
   /**
    * @param startAngle The angle at which to begin the gradient, in radians. Angle measurements start vertically above the centre and move around clockwise.
    * @param x The x-axis coordinate of the centre of the gradient.

src/lib.rs

@@ -84,12 +84,10 @@ impl CanvasElement {
     width: u32,
     height: u32,
   ) -> Result<ClassInstance<CanvasRenderingContext2D>> {
-    let ctx = CanvasRenderingContext2D::into_instance(
-      CanvasRenderingContext2D {
-        context: Context::new(width, height, ColorSpace::default())?,
-      },
-      env,
-    )?;
+    let ctx = CanvasRenderingContext2D {
+      context: Context::new(width, height, ColorSpace::default())?,
+    }
+    .into_instance(env)?;
     ctx.as_object(env).define_properties(&[
       Property::new(FILL_STYLE_HIDDEN_NAME)?
         .with_value(&env.create_string("#000")?)
@@ -108,6 +106,15 @@ impl CanvasElement {
     this.define_properties(&[Property::new("ctx")?
       .with_value(&ctx)
       .with_property_attributes(PropertyAttributes::Default)])?;
+    ctx
+      .as_object(env)
+      .define_properties(&[Property::new("canvas")?
+        .with_value(&this)
+        .with_property_attributes(
+          PropertyAttributes::Default
+            | PropertyAttributes::Writable
+            | PropertyAttributes::Enumerable,
+        )])?;
     Ok(Self { width, height, ctx })
   }