Here's the code:

import * as path from 'path';
import * as fs from 'fs';

const doesPathExist = async (path: string) => {
  return await fs.access(path, fs.constants.R_OK, (err) => {
    return err ? false : true;
  });
};

const someFunc = async (documentName: string) => {
  const documentPath = path.join(__dirname, documentName);
  const pathExists = doesPathExist(documentName);
};

The function doesPathExistseems to return Promise<void>, making the pathExists variable undefined no matter the outcome. I've tried initializing a temp variable at the top of the function before running fs.access and changing its value inside the callback but still no luck.

CodePudding user response：

The issue is with fs.access, this function does not return a Promise or anything else.

There are a few options to solve it.

1. you can always use fs.accessSync()

const doesPathExist = async (path: string) => {
  try {
    fs.accessSync(path, fs.constants.R_OK)
    return true
  } catch (e) {
    return false
  }
};

2. Use fs.promises

const fsPromises = fs.promises;

const doesPathExistB = async (path: string) => {
  try {
    await fsPromises.access(path, fs.constants.R_OK)
    return true
  } catch (e) {
    return false
  }
};
// OR
const doesPathExistA = async (path: string) => {
  return new Promise(async (resolve) => {
    await fsPromises.access(path, fs.constants.R_OK)
      .then(() => resolve(true))
      .catch(() => resolve(false))
  })
};