const expect = require('expect');
const invertKeyValues = require('./invertKeyValues.js');

test('invertKeyValues is a Function', () => {
  expect(invertKeyValues).toBeInstanceOf(Function);
});
test('invertKeyValues({ a: 1, b: 2, c: 1 }) returns { 1: [ \'a\', \'c\' ], 2: [ \'b\' ] }', () => {
  expect(invertKeyValues({ a: 1, b: 2, c: 1 })).toEqual({ 1: [ 'a', 'c' ], 2: [ 'b' ] });
});
test('invertKeyValues({ a: 1, b: 2, c: 1 }, value => \'group\' + value) returns { group1: [ \'a\', \'c\' ], group2: [ \'b\' ] }', () => {
  expect(invertKeyValues({ a: 1, b: 2, c: 1 }, value => 'group' + value)).toEqual( { group1: [ 'a', 'c' ], group2: [ 'b' ] });
});