Question

有标准的npm semver版本比较库，但是我这里有一些简单的逻辑来比较semver版本：

const versionA = '14.8.3';
const versionB = '15.1.1';
const versionC = '15.1.2';

const semver = require('semver');
const assert = require('assert');

const isGreater = (a, b) => {

  const [majorA, minorA, patchA] = String(a).split('.').map(v => Number.parseInt(v));
  const [majorB, minorB, patchB] = String(b).split('.').map(v => Number.parseInt(v));


  if (majorA > majorB) {
    return true;
  }

  if (majorB > minorA) {
    return false;
  }

  if (minorA > minorB) {
    return true;
  }

  if (minorB > minorA) {
    return false;
  }

  if (patchA > patchB) {
    return true;
  }

  if (patchB > patchA) {
    return false;
  }

  return false;

};


assert(isGreater(versionB, versionA), 'version b should be greater.');
assert(isGreater(versionA, versionB), 'version b should be greater.');

我的问题是-有没有一种方法可以简化GreaterThan函数中的逻辑？该功能应该复制semver.gt（）中的逻辑。

Answer 1

您可以改为使用localeCompare，通过numeric选项（与numeric进行比较，以使“ 1” <“ 2” <“ 10”）完全相同。您要寻找的逻辑：

const versionA = '14.8.3';
const versionB = '15.1.1';
const versionC = '15.1.2';
const versionD = '15.1.10';
const versionE = '15.2.1';
const versionF = '15.11.1';

const isGreater = (a, b) => {
  return a.localeCompare(b, undefined, { numeric: true }) === 1 ? true : false;
};

// first argument version comes later than second argument:
console.log(isGreater(versionB, versionA));
console.log(isGreater(versionC, versionB));
console.log(isGreater(versionD, versionC));
console.log(isGreater(versionE, versionD));
console.log(isGreater(versionF, versionE));

console.log('---');

// second comes before first:
console.log(isGreater(versionA, versionB));

// same, return value should be false:
console.log(isGreater(versionA, versionA));

或者等效地，您可以传递语言环境字符串

en-US-u-kn-true

作为第二个参数，而不是{ numeric: true }。

Answer 2

我相信这在逻辑上是相同且较短的，但就其简单性而言并不能令人惊叹

const isGreater = (a, b) => {

  const [majorA, minorA, patchA] = String(a).split('.').map(v => Number.parseInt(v));
  const [majorB, minorB, patchB] = String(b).split('.').map(v => Number.parseInt(v));

  if (majorA !== majorB) {
    return majorA > majorB;
  }

  if (minorA !== minorB) {
    return minorA > minorB;
  }

  return patchA > patchB;

};

简化semver版本比较逻辑

2 个答案: