javascript - 减少数组列表，以设置公共(public)路径

Question

我正在尝试将列表缩减为更短的列表，仅包含常见的文件系统路径。试图找到所有共同的祖 parent ，并只将那些放在最终列表中。以下是目标:目标是我们必须消除列表中存在父目录的所有目录。

更好的表达方式可能是:目标是我们必须消除列表中存在该路径父目录的所有路径。

假设我有这样的输入和预期的输出:

const input = [
  "/home/oleg/WebstormProjects/oresoftware/r2g",
  "/home/oleg/WebstormProjects/oresoftware/sumanjs/suman",
  "/home/oleg/WebstormProjects/oresoftware/sumanjs",
  "/home/oleg/WebstormProjects/oresoftware/sumanjs/suman-types",
  "/home/oleg/WebstormProjects/oresoftware/sumanjs/suman-watch"
];

const output = [
  "/home/oleg/WebstormProjects/oresoftware/r2g",
  "/home/oleg/WebstormProjects/oresoftware/sumanjs",
];

const getReducedList = function (input) {

  return input
  .sort((a, b) => (a.length - b.length))
  .reduce((a, b) => {

    // console.log('a:', a, 'b:', b);

    const s = !a.some(v => {
      return b.startsWith(v);
    });

    if (s) {
      a.push(b);
    }

    return a;

  }, []);

};

console.log(getReducedList(input));

那个getReducedList函数似乎适用于我们的第一个测试用例，5 减少到 2。但是，如果我们添加第二个测试用例，事情就会变得奇怪:

如果我从原始列表中删除一个项目并将其更改为这个包含 4 个的列表:

const input = [
  "/home/oleg/WebstormProjects/oresoftware/r2g",
  "/home/oleg/WebstormProjects/oresoftware/sumanjs/suman",
  "/home/oleg/WebstormProjects/oresoftware/sumanjs/suman-types",
  "/home/oleg/WebstormProjects/oresoftware/sumanjs/suman-watch"
];

然后我希望得到这个输出(相同的 4 列表):

const output = [
  "/home/oleg/WebstormProjects/oresoftware/r2g",
  "/home/oleg/WebstormProjects/oresoftware/sumanjs/suman",
  "/home/oleg/WebstormProjects/oresoftware/sumanjs/suman-types",
  "/home/oleg/WebstormProjects/oresoftware/sumanjs/suman-watch"
];

我期望/想要相同的 4 列表的原因是因为列表中的任何项目都没有列表其他地方的父目录。但我实际上得到了这个输出，一个 2 的列表，这是不正确的:

const output =  [ 
   '/home/oleg/WebstormProjects/oresoftware/r2g',
   '/home/oleg/WebstormProjects/oresoftware/sumanjs/suman' 
];

有谁知道我该如何解决这个问题以获得预期的结果？答案需要满足两个测试用例。

为了清楚起见，如果您添加 "/home/oleg"到原始列表，然后"/home/oleg"应该是输出中的唯一条目。

Answer 1

我想你可以用一个非常简单的递归函数来做到这一点。您只需按长度排序，然后递归弹出最短的，将其添加到结果中，用它过滤数组，递归:

const input = [
    "/home/oleg/WebstormProjects/oresoftware/r2g",
    "/home/oleg/WebstormProjects/oresoftware/sumanjs/suman",
    "/home/oleg/WebstormProjects/oresoftware/sumanjs",
    "/home/oleg/WebstormProjects/oresoftware/sumanjs/suman-types",
    "/home/oleg/WebstormProjects/oresoftware/sumanjs/suman-watch"
  ];
  
input.sort((a,b) => b.length - a.length)
function getPrefixes(list, res =[]) {
    if (list.length < 1) return res
    let next = list.pop()
    res.push(next)
    return getPrefixes(list.filter(u => !u.startsWith(next + '/')), res)

}
console.log(getPrefixes(input))