fix: add ctx.canvas property on svg context (#697)

* add ctx.canvas on svg context

* add ctx.canvas test for svg canvas

* lint fix

__test__/canvas-class.spec.ts

@@ -19,3 +19,9 @@ test('ctx.canvas should be equal to canvas', (t) => {
   const ctx = canvas.getContext('2d')
   t.is(ctx.canvas, canvas)
 })
+
+test('[SVG] ctx.canvas should be equal to canvas', (t) => {
+  const canvas = createCanvas(100, 100, SvgExportFlag.NoPrettyXML)
+  const ctx = canvas.getContext('2d')
+  t.is(ctx.canvas, canvas)
+})

src/lib.rs

@@ -469,6 +469,13 @@ impl SVGCanvas {
       Property::new(STROKE_STYLE_HIDDEN_NAME)?
         .with_value(&env.create_string("#000")?)
         .with_property_attributes(PropertyAttributes::Writable | PropertyAttributes::Configurable),
+      Property::new("canvas")?
+        .with_value(&this)
+        .with_property_attributes(
+          PropertyAttributes::Default
+            | PropertyAttributes::Writable
+            | PropertyAttributes::Enumerable,
+        ),
     ])?;
     env.adjust_external_memory((width * height * 4) as i64)?;
     this.define_properties(&[Property::new("ctx")?