fix(RTTR): implement HTMLCanvasElement.getContext

packages/test-renderer/src/createTestCanvas.ts

@@ -2,20 +2,31 @@ import { WebGL2RenderingContext } from './WebGL2RenderingContext'
 import type { CreateCanvasParameters } from './types/internal'
 
 export const createCanvas = ({ beforeReturn, width = 1280, height = 800 }: CreateCanvasParameters = {}) => {
-  const canvas =
-    typeof document !== 'undefined' && typeof document.createElement === 'function'
-      ? document.createElement('canvas')
-      : ({
-          style: {},
-          addEventListener: (() => {}) as any,
-          removeEventListener: (() => {}) as any,
-          clientWidth: width,
-          clientHeight: height,
-          getContext: (() => new WebGL2RenderingContext(canvas)) as any,
-        } as HTMLCanvasElement)
+  let canvas: HTMLCanvasElement
+
+  if (typeof document !== 'undefined' && typeof document.createElement === 'function') {
+    canvas = document.createElement('canvas')
+  } else {
+    canvas = {
+      style: {},
+      addEventListener: (() => {}) as any,
+      removeEventListener: (() => {}) as any,
+      clientWidth: width,
+      clientHeight: height,
+      getContext: (() => new WebGL2RenderingContext(canvas)) as any,
+    } as HTMLCanvasElement
+  }
   canvas.width = width
   canvas.height = height
 
+  if (globalThis.HTMLCanvasElement) {
+    const getContext = HTMLCanvasElement.prototype.getContext
+    HTMLCanvasElement.prototype.getContext = function (id: string) {
+      if (id.startsWith('webgl')) return new WebGL2RenderingContext(this)
+      return getContext.apply(this, arguments as any)
+    } as any
+  }
+
   beforeReturn?.(canvas)
 
   class WebGLRenderingContext extends WebGL2RenderingContext {}