refactor: swap jsdom + canvas dep in favour of a mock object

Signed-off-by: André Jaenisch <andre.jaenisch@posteo.de>

package.json

@@ -50,7 +50,6 @@
     "@rollup/plugin-buble": "0.21.3",
     "@rollup/plugin-commonjs": "20.0.0",
     "@rollup/plugin-node-resolve": "13.0.4",
-    "canvas": "2.8.0",
     "chai": "4.3.4",
     "clean-css-cli": "5.3.3",
     "eslint": "7.32.0",
@@ -65,7 +64,6 @@
     "jsdoc": "3.6.7",
     "jsdoc-mermaid": "1.0.0",
     "jsdoc-tsimport-plugin": "1.0.5",
-    "jsdom": "17.0.0",
     "markdownlint-cli": "0.28.1",
     "mocha": "9.0.3",
     "npm": "7.20.6",

test/js/draw.test.js

@@ -1,20 +1,13 @@
 import { expect } from 'chai'
-import jsdom from 'jsdom'
 
 import { drawShape } from '../../src/js/draw.js'
 import { RigidShape } from '../../src/js/shape.js'
 import { Vec2 } from '../../src/js/vector.js'
 
-// Requires npm canvas package here to be installed
-const { JSDOM } = jsdom
-const { window } = new JSDOM('')
-const { document } = window
-
 describe('drawShape', function () {
   it('should draw a shape onto a canvas', function () {
     // Arrange
-    const canvas = document.createElement('canvas')
-    const context = canvas.getContext('2d')
+    const context = makeContext()
     const center = Vec2(500, 200)
     const friction = 20
     const restitution = 0
@@ -40,3 +33,13 @@ describe('drawShape', function () {
     // TODO: Assert pixel on canvas
   })
 })
+
+function makeContext () {
+  return {
+    restore: function () {},
+    rotate: function () {},
+    save: function () {},
+    strokeRect: function () {},
+    translate: function () {},
+  }
+}