Add a Docker Compose config file for testing the setup locally

docker-compose.yml

@@ -0,0 +1,29 @@
+# Docker Compose setup file
+# Purpose: testbed for changes to Circle CI setup
+# Usage: `docker-compose up`
+version: "3"
+services:
+  node:
+    image: "circleci/node:10.15.1-browsers"
+    user: "root"
+    working_dir: /home/node/app
+
+    # use the one built-in to the image to avoid potential issues like
+    # https://github.com/GoogleChrome/puppeteer/issues/3774
+    # This variable is used by all scripts - including the `test-esm-bundle`
+    environment:
+      PUPPETEER_SKIP_CHROMIUM_DOWNLOAD: 'true'
+      SINON_CHROME_BIN: /usr/bin/google-chrome-stable
+    volumes:
+      # This mounts the local directory - saving `npm install`
+      - ./:/home/node/app
+    command: >
+      sh -c "
+      $$SINON_CHROME_BIN --version
+
+      npm run test-headless -- --chrome $$SINON_CHROME_BIN --allow-chrome-as-root
+      && npm run test-webworker -- --chrome $$SINON_CHROME_BIN --allow-chrome-as-root
+      && npm run test-esm-bundle
+      && npm run test-node
+
+      "