SOURCE

var natural= function(min, max) {
    min = typeof min !== 'undefined' ? parseInt(min, 10) : 0
    max = typeof max !== 'undefined' ? parseInt(max, 10) : 9007199254740992 // 2^53
    return Math.round(Math.random() * (max - min)) + min
}

console.info(Math.random());
console.info(natural(1.5,5));
console.info(natural(1,5));

console.log(Mock.Random.character('aeiou'));
console.log(Mock.Random.string(3));
console.log(Mock.Random.string('lower'));


var patternLetters = {
    yyyy: 'getFullYear',
    yy: function(date) {
        return ('' + date.getFullYear()).slice(2)
    },
    y: 'yy',

    MM: function(date) {
        var m = date.getMonth() + 1
        return m < 10 ? '0' + m : m
    },
    M: function(date) {
        return date.getMonth() + 1
    },

    dd: function(date) {
        var d = date.getDate()
        return d < 10 ? '0' + d : d
    },
    d: 'getDate',

    HH: function(date) {
        var h = date.getHours()
        return h < 10 ? '0' + h : h
    },
    H: 'getHours',
    hh: function(date) {
        var h = date.getHours() % 12
        return h < 10 ? '0' + h : h
    },
    h: function(date) {
        return date.getHours() % 12
    },

    mm: function(date) {
        var m = date.getMinutes()
        return m < 10 ? '0' + m : m
    },
    m: 'getMinutes',

    ss: function(date) {
        var s = date.getSeconds()
        return s < 10 ? '0' + s : s
    },
    s: 'getSeconds',

    SS: function(date) {
        var ms = date.getMilliseconds()
        return ms < 10 && '00' + ms || ms < 100 && '0' + ms || ms
    },
    S: 'getMilliseconds',

    A: function(date) {
        return date.getHours() < 12 ? 'AM' : 'PM'
    },
    a: function(date) {
        return date.getHours() < 12 ? 'am' : 'pm'
    },
    T: 'getTime'
};
function format(){
    var re = []
    for (var i in patternLetters) re.push(i)
    return '(' + re.join('|') + ')'
}
var _rformat = new RegExp(format(),'g');
console.info(format(),_rformat);
console.info(new Date(0));
var _randomDate = function(min, max) { // min, max
    min = min === undefined ? new Date(0) : min
    max = max === undefined ? new Date() : max
    return new Date(Math.random() * (max.getTime() - min.getTime()))
}
console.info(_randomDate());

var _formatDate = function(date, format) {
    return format.replace(_rformat, function creatNewSubString($0,flag,flag2,me) {
        console.info({$0,flag,flag2,me});
        return typeof patternLetters[flag] === 'function' ? patternLetters[flag](date) :
            patternLetters[flag] in patternLetters ? creatNewSubString($0, patternLetters[flag]) :
            date[patternLetters[flag]]()
    })
}
var _randomDate= function(min, max) { // min, max
    min = min === undefined ? new Date(0) : min
    max = max === undefined ? new Date() : max
    return new Date(Math.random() * (max.getTime() - min.getTime()))
}
_formatDate(_randomDate(),'yyyy-MM-dd');

var date = new Date();
console.info({'getDate':date.getDate(),'getDay':date.getDay()});
console.info(date.setDate(date.getDate() - date.getDay()));

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