Koan es6katas, 18: rest - as-parameter, Argumentos ...rest,
Kata // 18: rest - as-parameter
// 18: rest - as-parameter
// To do: make all tests pass, leave the assert lines unchanged!
describe('rest in function params', () => {
it('must be the last parameter', () => {
const fn = (...rest) => {
assert.deepEqual([1, 2], rest);
};
fn(1, 2);
});
it('can be used to get all other parameters', () => {
const fn = (firstParam, secondParam, ...rest) => {
assert.deepEqual([3,4], rest);
};
fn(null, 2, 3, 4);
});
it('makes `arguments` obsolete', () => {
const fn = (...args) => {
assert.deepEqual([42, 'twenty three', 'win'], args);
};
fn(42, 'twenty three', 'win');
});
it('eliminate `arguments`!!!', () => {
const fn = (...args) =>{return args};
const [firstArg, ...rest] = fn(1, 2, 3); //destructuring assignment
assert.deepEqual([2, 3], rest);
});
});