How to create full path with node's fs.mkdirSync?, Node.js

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const fs = require('fs');
const path = require('path');

function mkDirByPathSync(targetDir, opts) {
  const isRelativeToScript = opts && opts.isRelativeToScript;
  const sep = path.sep;
  const initDir = path.isAbsolute(targetDir) ? sep : '';
  const baseDir = isRelativeToScript ? __dirname : '.';
  const lastErr;

targetDir.split(sep).reduce((parentDir, childDir) => {
    const curDir = path.resolve(baseDir, parentDir, childDir);
    try {
      fs.mkdirSync(curDir);
      console.log(`Directory ${curDir} created!`);  
    } catch (err) {
      if (err.code === 'EEXIST') { // Directory ${curDir} already exists!
        console.log(`Directory ${curDir} already exists!`);  
        return curDir;
      }

// The following lines of code to support Windows and Mac specific errors.
      if (err.code === 'ENOENT') { // Last dir fails with `EACCES` and current fails with `ENOENT`
        throw lastErr;
      }

const caughtErr = ['EACCES', 'EPERM', 'EISDIR'].indexOf(err.code) > -1;
      if (!caughtErr || caughtErr && targetDir === curDir) {
        throw err; // Throw if it's only the last created dir.
      }

lastErr = err;
    }

return curDir;
  }, initDir);
}

// Usage
mkDirByPathSync('/path/to/dir');

// Or
mkDirByPathSync('path/to/dir', {isRelativeToScript: true});

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Absolute running time: 0.17 sec, cpu time: 0.15 sec, memory peak: 15 Mb, absolute service time: 0,18 sec