message: Use prettier check
diff: "clean": "rm -rf build && rm -f src/style.ts && mkdir build",
  "prettierbase": "prettier '{src,test}/**/*.ts' '*.scss' '*.html' '*.js'",
  "format": "tslint -p . -e 'package.json' --fix && npm run prettierbase -- --write",
  - "lint": "tslint -p . -e 'package.json' && npm run prettierbase -- --list-different",
  + "lint": "tslint -p . -e 'package.json' && npm run prettierbase -- --check",
  "postbuild": "terser build/vega-embed.js -cm > build/vega-embed.min.js",
  "prepublishOnly": "npm run build",
  "preversion": "npm run lint && npm run test",
  