Javascript中罗马数字Kata的重构

我是Javascript中罗马数字Kata的新手。 所有规格都合格。我已经重构了spec文件，现在正试图重构主文件

过去的样子是这样的：

function roman(number) {
  var conversion = ''

  if (number == 100){
    conversion += 'C'
    number -= 100
  }
// omitted code

  while (number >= 1){
   conversion += 'I'
   number -= 1
 }

return conversion
}

function roman(number) {

  var denominations = {

    100: 'C',
    // omitted code
    5: 'V',
    4: 'IV',
    1: 'I'

  }

  var conversions = ''

  _.each(denominations, function(roman_num, natural_num) {
    while (number >= natural_num){ 
      conversions = conversions + roman_num
      number -= natural_num
    }
  })
  return conversions
}

Expected 'IIII' to equal 'IV'
Expected 'IIIII' to equal 'V'

现在看起来是这样的：

function roman(number) {
  var conversion = ''

  if (number == 100){
    conversion += 'C'
    number -= 100
  }
// omitted code

  while (number >= 1){
   conversion += 'I'
   number -= 1
 }

return conversion
}

function roman(number) {

  var denominations = {

    100: 'C',
    // omitted code
    5: 'V',
    4: 'IV',
    1: 'I'

  }

  var conversions = ''

  _.each(denominations, function(roman_num, natural_num) {
    while (number >= natural_num){ 
      conversions = conversions + roman_num
      number -= natural_num
    }
  })
  return conversions
}

Expected 'IIII' to equal 'IV'
Expected 'IIIII' to equal 'V'

我花了一些时间通过Chrome使用JS控制台进行调试，它看起来没有遍历每个面额，而是停留在1

我还使用了Jasmine，因此我的错误如下所示：

function roman(number) {
  var conversion = ''

  if (number == 100){
    conversion += 'C'
    number -= 100
  }
// omitted code

  while (number >= 1){
   conversion += 'I'
   number -= 1
 }

return conversion
}

function roman(number) {

  var denominations = {

    100: 'C',
    // omitted code
    5: 'V',
    4: 'IV',
    1: 'I'

  }

  var conversions = ''

  _.each(denominations, function(roman_num, natural_num) {
    while (number >= natural_num){ 
      conversions = conversions + roman_num
      number -= natural_num
    }
  })
  return conversions
}

Expected 'IIII' to equal 'IV'
Expected 'IIIII' to equal 'V'

等等

因此，我的问题是： 1.为什么它只能返回1“I”的值 和 2.我怎么修理它

---

提前谢谢

JavaScript对象是以字符串作为索引的HashMap。因此，不能保证“u.each”中元素的顺序与声明的顺序相同。您应该使用保证有序数组的结构

function roman(number) {
  var denominations_natural = [100, 5, 4, 1];
  var denominations_roman = ["C", "V", "IV", "I"];

  var conversions = '';

  for (var i=0; i<denominations_natural.length; i++) {
    while (number >= denominations_natural[i]) {
      conversions += denominations_roman[i];
      number -= denominations_natural[i];
    }
  }

  return conversions;
}

函数罗马（数字）{
var面额_natural=[100,5,4,1]；
var面额罗马=[“C”、“V”、“IV”、“I”]；
var转换=“”；
对于（var i=0；i=面额_自然[i]）{
兑换率+=罗马面额[i]；
数字-=面额自然[i]；
}
}
返回转换；
}