Creating and removing directories in Node.js - Practice Exercises

Challenge - 5 Problems

❓ Predict Output

intermediate

Output of directory creation with recursive option

What will be the output of this Node.js code snippet when creating nested directories?

Node.js

import { mkdirSync } from 'node:fs';

try {
  mkdirSync('parent/child/grandchild', { recursive: true });
  console.log('Directories created');
} catch (error) {
  console.log('Error:', error.message);
}

A No output

B Error: ENOENT: no such file or directory, mkdir 'parent/child/grandchild'

C Directories created

D Error: EEXIST: file already exists, mkdir 'parent/child/grandchild'

💡 Hint

The recursive option allows creating nested directories even if parent folders don't exist.

Using mkdirSync with { recursive: true } creates all missing parent directories. So the nested path is created successfully and the message 'Directories created' is logged.

❓ Predict Output

intermediate

Behavior of rmdirSync on non-empty directory

What happens when this Node.js code tries to remove a non-empty directory?

Node.js

import { rmdirSync } from 'node:fs';

try {
  rmdirSync('myFolder');
  console.log('Directory removed');
} catch (error) {
  console.log(error.code);
}

A Directory removed

B EACCES

C ENOENT

D ENOTEMPTY

💡 Hint

rmdirSync cannot remove directories that contain files or folders unless recursive option is used.

rmdirSync throws an error with code 'ENOTEMPTY' if the directory is not empty and recursive option is not set.

📝 Syntax

advanced

Correct syntax for recursive directory removal

Which option correctly removes a directory and all its contents recursively in Node.js?

A rmdirSync('folder', { recursive: true });

B rmdirSync('folder', true);

C rmdirSync('folder', { force: true });

D rmdirSync('folder', { deep: true });

💡 Hint

The recursive option is an object property, not a boolean argument or other name.

The correct syntax uses an options object with recursive:true to remove directories with contents.

❓ component_behavior

advanced

Effect of mkdirSync without recursive on nested path

What happens when mkdirSync is called without recursive on a nested path where parent folders don't exist?

Node.js

import { mkdirSync } from 'node:fs';

try {
  mkdirSync('a/b/c');
  console.log('Created');
} catch (error) {
  console.log(error.code);
}

A ENOENT

B EEXIST

C Created

D EPERM

💡 Hint

Without recursive:true, mkdirSync cannot create nested directories if parents are missing.

The error code ENOENT means a parent directory does not exist, so mkdirSync fails without recursive.

🔧 Debug

expert

Why does this directory removal code fail?

Given this code snippet, why does it throw an error when trying to remove 'tempDir'?

Node.js

import { rmdirSync } from 'node:fs';

rmdirSync('tempDir');

A tempDir path is incorrect, causing ENOENT error

B tempDir contains files or subdirectories, so rmdirSync fails without recursive:true

C rmdirSync requires a callback function, so this call is invalid

D rmdirSync cannot remove directories on Windows

💡 Hint

Check if the directory is empty before removing without recursive option.

rmdirSync throws an error if the directory is not empty and recursive:true is not specified.

Practice

1. Which Node.js method is used to create a new directory?

easy

A. fs.createDir()

B. fs.rmdir()

C. fs.deleteDir()

D. fs.mkdir()

Solution

1. Step 1: Understand directory creation methods

   Node.js provides fs.mkdir() to create directories.

2. Step 2: Differentiate from removal methods

   fs.rmdir() is for removing directories, not creating.

3. Final Answer:

   fs.mkdir() -> Option D

4. Quick Check:

   Create directory = fs.mkdir() [OK]

Hint: Use fs.mkdir() to create folders, not fs.rmdir() [OK]

Common Mistakes:

• Confusing fs.mkdir() with fs.rmdir()
• Using non-existent fs.createDir()
• Trying to use fs.deleteDir() which doesn't exist

2. Which of the following is the correct syntax to create a nested directory parent/child in Node.js?

easy

A. fs.mkdir('parent/child', callback)

B. fs.mkdir('parent/child', { recursive: true }, callback)

C. fs.rmdir('parent/child', { recursive: true }, callback)

D. fs.mkdir('parent/child', { nested: true }, callback)

Solution

1. Step 1: Recognize recursive option for nested folders

   To create nested directories, use { recursive: true } option with fs.mkdir().

2. Step 2: Confirm correct method and options

   fs.mkdir with recursive true creates all needed folders; fs.rmdir is for removal, and nested option doesn't exist.

3. Final Answer:

   fs.mkdir('parent/child', { recursive: true }, callback) -> Option B

4. Quick Check:

   Nested folders need recursive: true [OK]

Hint: Use { recursive: true } with fs.mkdir for nested folders [OK]

Common Mistakes:

• Omitting recursive option for nested directories
• Using fs.rmdir instead of fs.mkdir
• Using incorrect option name like nested

3. What will happen if you run the following code snippet in Node.js?

const fs = require('fs');
fs.rmdir('myFolder', (err) => {
  if (err) console.log('Error:', err.message);
  else console.log('Folder removed');
});

Assuming myFolder contains files.

medium

A. Folder is removed successfully

B. Code throws a syntax error

C. Error logged because folder is not empty

D. Folder is renamed instead of removed

Solution

1. Step 1: Understand fs.rmdir behavior

   fs.rmdir only removes empty directories; if folder has files, it throws an error.

2. Step 2: Analyze error handling in callback

   The callback logs error message if removal fails due to non-empty folder.

3. Final Answer:

   Error logged because folder is not empty -> Option C

4. Quick Check:

   Non-empty folder removal = error [OK]

Hint: fs.rmdir fails if folder has files; must delete files first [OK]

Common Mistakes:

• Assuming fs.rmdir removes non-empty folders
• Expecting folder rename instead of removal
• Thinking code throws syntax error

4. Identify the error in this code snippet that tries to remove a directory:

const fs = require('fs');
fs.rmdir('testDir', { recursive: true }, (err) => {
  if (err) throw err;
  console.log('Directory removed');
});

medium

A. fs.rmdir does not support recursive option

B. Callback function is missing

C. fs.rmdir cannot remove directories

D. Directory path must be absolute

Solution

1. Step 1: Check fs.rmdir method options

   fs.rmdir does not support the recursive option; fs.rm should be used instead for recursive removal.

2. Step 2: Understand correct method for recursive removal

   Use fs.rm with { recursive: true } to remove non-empty directories recursively.

3. Final Answer:

   fs.rmdir does not support recursive option -> Option A

4. Quick Check:

   Recursive removal needs fs.rm, not fs.rmdir [OK]

Hint: Use fs.rm for recursive removal, not fs.rmdir [OK]

Common Mistakes:

• Using recursive option with fs.rmdir
• Thinking callback is missing
• Believing directory path must be absolute

5. You want to create a nested directory projects/app/src and then remove it completely including all files inside. Which sequence of Node.js methods should you use?

hard

A. Use fs.mkdir with { recursive: true } to create, then fs.rm with { recursive: true, force: true } to remove

B. Use fs.mkdir without options to create, then fs.rmdir to remove

C. Use fs.mkdir with { recursive: true } to create, then fs.rmdir to remove

D. Use fs.mkdir to create, then fs.unlink to remove

Solution

1. Step 1: Create nested directories

   Use fs.mkdir with { recursive: true } to create nested folders in one step.

2. Step 2: Remove directory with all contents

   Use fs.rm with { recursive: true, force: true } to delete directory and all files inside safely.

3. Final Answer:

   Use fs.mkdir with { recursive: true } to create, then fs.rm with { recursive: true, force: true } to remove -> Option A

4. Quick Check:

   Nested create + recursive remove = fs.mkdir + fs.rm [OK]

Hint: Create nested with mkdir recursive, remove all with rm recursive force [OK]

Common Mistakes:

• Using fs.rmdir to remove non-empty directories
• Omitting recursive option when creating nested folders
• Using fs.unlink which deletes files, not folders