这样么？

修正一把：

再来修正一把

var diffMonths = function(date1, date2) {
    var a = moment(date1);
    var b = moment(date2);
    var diff = b.format('YM') - a.format('YM');
    diff = b.format('Y') !== a.format('Y') ? diff + 2 : diff;

    return Array.apply([], new Array(diff + 1)).map(function(item, index) {
        return a.clone().add(index, 'months').format('YYYY-MM');
    });
};


console.log(diffMonths([2016, 0, 15], [2016, 6, 31]));
console.log(diffMonths([2016, 6, 31], [2016, 7, 1]));
console.log(diffMonths([2016, 6, 1], [2016, 6, 31]));
console.log(diffMonths([2016, 6, 31], [2016, 8, 1]));
console.log(diffMonths([2016, 6, 31], [2017, 8, 1]));
console.log(diffMonths([2016, 6, 31], [2017, 0, 1]));

我看了你最后一次提供的做法，光比较月份的话，最后两个case是跑不通的，所以才想到再改一次。万没想到，这么个小东西也确实写了好久