Gettie is a JS object coverage tool.

Originally it developed to extract redux store coverage to find out which store branches were not used till the application works.

const state = {
  foo: 123,
  bar: [456, { baz: 789 }],
  quux: 123
};

console.log(state.quux);
console.log(state.bar[1].baz);

It helps to find out that branches foo and bar[0] from the state were not used. It may motivate you to think about what you can do to remove the unused branches.

For more information, please, see core package.