kata.js

// 41: array - entries
// To do: make all tests pass, leave the assert lines unchanged!

describe('`[].entries()` returns an iterator object with all entries', function() {

  it('returns key+value for each element', function() {
    const arr = ['a', 'b', 'c'];
    const entriesAsArray = Array.from(arr.___());

    assert.deepEqual(entriesAsArray, [[0,"a"], [1,"b"], [2,"c"]]);
  });

  it('empty elements contain the value `undefined`', function() {
    const arr = ['one'];
    arr[2] = 'three';
    const secondValue = arr.entries();

    assert.deepEqual(secondValue, [1, void 0]);
  });

  describe('returns an iterable', function() {

    it('has `next()` to iterate', function() {
      const arr = ['one'];
      const value = arr;

      assert.deepEqual(value, [0, 'one']);
    });

  });

});