path.parse and path.format in Node.js - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to parse a file path into its parts using path.parse.

Node.js

const path = require('path');
const parsed = path.[1]('/home/user/file.txt');
console.log(parsed);

Drag options to blanks, or click blank then click option'

Abasename

Bformat

Cjoin

Dparse

Attempts:

3 left

💡 Hint

Common Mistakes

Using path.format instead of path.parse

Using path.basename which only returns the file name

The path.parse method breaks a file path into its parts like root, dir, base, ext, and name.

2fill in blank

medium

Complete the code to create a path string from an object using path.format.

Node.js

const path = require('path');
const obj = { root: '/', dir: '/home/user', base: 'file.txt' };
const fullPath = path.[1](obj);
console.log(fullPath);

Drag options to blanks, or click blank then click option'

Aparse

Bformat

Cresolve

Dbasename

Attempts:

3 left

💡 Hint

Common Mistakes

Using path.parse which does the opposite

Using path.resolve which resolves absolute paths

The path.format method builds a path string from an object with parts like root, dir, base, etc.

3fill in blank

hard

Fix the error in the code to correctly parse the path '/var/log/sys.log'.

Node.js

const path = require('path');
const parts = path.[1]('/var/log/sys.log');
console.log(parts.ext);

Drag options to blanks, or click blank then click option'

Aparse

Bformat

Cjoin

Dbasename

Attempts:

3 left

💡 Hint

Common Mistakes

Using path.format which expects an object

Using path.basename which returns only the file name

To get parts of a path, use path.parse. Using format or others will cause errors or wrong results.

4fill in blank

hard

Fill both blanks to parse a path and then format it back to a string.

Node.js

const path = require('path');
const parsed = path.[1]('/etc/nginx/nginx.conf');
const formatted = path.[2](parsed);
console.log(formatted);

Drag options to blanks, or click blank then click option'

Aparse

Bjoin

Cformat

Dbasename

Attempts:

3 left

💡 Hint

Common Mistakes

Using format before parse

Using join or basename which do different things

First, use parse to split the path, then format to join it back into a string.

5fill in blank

hard

Fill all three blanks to parse a path, change its base, and format it back.

Node.js

const path = require('path');
const parsed = path.[1]('/usr/local/bin/script.sh');
parsed.base = '[2]';
parsed.name = '[3]';
const newPath = path.format(parsed);
console.log(newPath);

Drag options to blanks, or click blank then click option'

Aformat

Bscript_backup.sh

Cscript_backup

Dparse

Attempts:

3 left

💡 Hint

Common Mistakes

Changing base but not name

Using format instead of parse to get parts

Use parse to get parts, then change base and name, and finally format to build the new path.

Practice

1. What does path.parse do in Node.js?

easy

A. It breaks a file path into parts like root, dir, base, name, and ext.

B. It combines multiple file paths into one string.

C. It reads the contents of a file at the given path.

D. It deletes a file at the specified path.

Solution

1. Step 1: Understand the purpose of path.parse

   path.parse takes a file path string and splits it into an object with properties like root, dir, base, name, and ext.

2. Step 2: Compare with other options

   Options A, C, and D describe different file system operations, not path parsing.

3. Final Answer:

   It breaks a file path into parts like root, dir, base, name, and ext. -> Option A

4. Quick Check:

   path.parse splits path into parts [OK]

Hint: Remember: parse means split path into pieces [OK]

Common Mistakes:

• Confusing path.parse with reading file contents
• Thinking path.parse combines paths
• Mixing up path.parse with deleting files

2. Which of the following is the correct way to use path.format to build a path from parts?

easy

A. path.format('file.txt')

B. path.format('/home/user/file.txt')

C. path.format({ root: '/', dir: '/home/user', base: 'file.txt' })

D. path.format(['home', 'user', 'file.txt'])

Solution

1. Step 1: Identify correct argument type for path.format

   path.format expects an object with path parts like root, dir, base, name, or ext.

2. Step 2: Check each option

   path.format({ root: '/', dir: '/home/user', base: 'file.txt' }) correctly passes an object with root, dir, and base. Options B, C, and D pass strings or arrays, which are invalid.

3. Final Answer:

   path.format({ root: '/', dir: '/home/user', base: 'file.txt' }) -> Option C

4. Quick Check:

   path.format needs object with parts [OK]

Hint: path.format needs an object, not a string or array [OK]

Common Mistakes:

• Passing a string instead of an object to path.format
• Using an array instead of an object
• Confusing path.format with path.parse usage

3. What is the output of this code?

const path = require('path');
const parsed = path.parse('/home/user/docs/file.txt');
console.log(parsed.base);

medium

A. '/home/user/docs/file.txt'

B. 'file.txt'

C. 'file'

D. '.txt'

Solution

1. Step 1: Understand what path.parse returns

   path.parse returns an object with properties including base, which is the last part of the path with extension.

2. Step 2: Check the base property for given path

   For '/home/user/docs/file.txt', base is 'file.txt'.

3. Final Answer:

   'file.txt' -> Option B

4. Quick Check:

   parsed.base = 'file.txt' [OK]

Hint: base is filename with extension from path.parse [OK]

Common Mistakes:

• Confusing base with dir or name
• Expecting full path instead of base
• Mixing base with extension only

4. Identify the error in this code snippet:

const path = require('path');
const parts = path.parse('/var/log/sys.log');
const newPath = path.format(parts.dir + '/backup/' + parts.base);
console.log(newPath);

medium

A. path.format expects an object, but a string was passed.

B. path.parse cannot parse absolute paths.

C. The variable parts is not defined.

D. The console.log statement is missing parentheses.

Solution

1. Step 1: Check the argument passed to path.format

   path.format requires an object with path parts, but here a string is passed by concatenating parts.dir, '/backup/', and parts.base.

2. Step 2: Understand correct usage of path.format

   To add '/backup/' folder, modify parts.dir property or create a new object, then pass that object to path.format.

3. Final Answer:

   path.format expects an object, but a string was passed. -> Option A

4. Quick Check:

   path.format needs object, not string [OK]

Hint: path.format always needs an object, never a string [OK]

Common Mistakes:

• Passing a string instead of an object to path.format
• Assuming path.parse fails on absolute paths
• Forgetting parentheses in console.log (not true here)

5. Given this code, what will console.log(newPath) output?

const path = require('path');
const parts = path.parse('/usr/local/bin/node');
const updatedParts = { ...parts, dir: parts.dir + '/backup' };
const newPath = path.format(updatedParts);
console.log(newPath);

hard

A. '/usr/local/bin/backup/'

B. '/usr/local/bin/node/backup'

C. '/usr/local/bin/node'

D. '/usr/local/bin/backup/node'

Solution

1. Step 1: Analyze how updatedParts modifies dir

   updatedParts copies all parts but changes dir to parts.dir + '/backup', so dir becomes '/usr/local/bin/backup'.

2. Step 2: Understand path.format output

   path.format builds path from updatedParts, combining dir and base ('node'), resulting in '/usr/local/bin/backup/node'.

3. Final Answer:

   '/usr/local/bin/backup/node' -> Option D

4. Quick Check:

   Modified dir + base = '/usr/local/bin/backup/node' [OK]

Hint: Changing dir in parts changes folder path in output [OK]

Common Mistakes:

• Appending backup to base instead of dir
• Confusing order of path parts
• Forgetting to spread parts before modifying