Jest test for DrawerHelper JS

.github/test.yml

@@ -0,0 +1,31 @@
+
+
+name: Run Tests
+
+on:
+  pull_request:
+    branches:
+      - master
+      - develop
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v2
+
+      - name: Set up Node.js
+        uses: actions/setup-node@v3
+        with:
+          node-version: '16.x'  
+
+      - name: Install dependencies and ESLint
+        run: |
+          npm install
+          npm install eslint eslint-config-google
+
+      - name: Run Jest tests and linting
+        run: |
+          npm run lint && npm test

common/DrawHelper.js

@@ -325,4 +325,8 @@ caDrawHelper.prototype.clearCanvas = function(canvas){
 }
 
 var DrawHelper = new caDrawHelper();
-//OpenSeadragon.DrawHelper = DrawHelper;
+//OpenSeadragon.DrawHelper = DrawHelper;
+
+
+
+module.exports = caDrawHelper;