https://github.com/google/gts/issues/347

file.ts

export function sum(
  forSomeReasonThisIsAVeryLongVariableName1: number,
  forSomeReasonThisIsAVeryLongVariableName2: number,
): number {
  return (
    forSomeReasonThisIsAVeryLongVariableName1 +
    forSomeReasonThisIsAVeryLongVariableName2
  );
}

package.json

{
  "name": "test",
  "version": "1.0.0",
  "main": "index.js",
  "license": "MIT",
  "devDependencies": {
    "gts": "^1.0.0",
    "typescript": "~3.4.0"
  }
}

prettier.config.js

module.exports = {
  singleQuote: true,
  trailingComma: 'all',
};

tsconfig.json

{
  "extends": "./node_modules/gts/tsconfig-google.json",
  "compilerOptions": {
    "rootDir": ".",
    "outDir": "build"
  },
  "include": ["**/*.ts"]
}

tslint.json

{
  "extends": "gts/tslint.json",
  "linterOptions": {
    "exclude": ["**/*.json"]
  }
}