Rubocop for linting in Ruby - Mini Project: Build & Apply

Using Rubocop for Linting Ruby Code

📖 Scenario: You are working on a small Ruby project and want to keep your code clean and consistent. You will use Rubocop, a popular Ruby tool, to check your code style and find mistakes.

🎯 Goal: Learn how to set up a Ruby file, configure Rubocop with a simple setting, run Rubocop to check your code, and see the linting results.

📋 What You'll Learn

Create a Ruby file with some code

Add a Rubocop configuration variable

Run Rubocop linting using Ruby code

Print the Rubocop linting output

💡 Why This Matters

🌍 Real World

Rubocop helps Ruby developers keep their code clean and consistent by automatically checking style and common mistakes.

💼 Career

Many Ruby jobs require using Rubocop or similar tools to maintain high-quality code and follow team style guides.

1

Create a Ruby file with code

Create a Ruby file named example.rb with this exact code: def greet(name) puts "Hello, #{name}!" end

Ruby

# Create the file example.rb with the greet method
# Your code here

Need a hint?

Define a method called greet that takes name and prints a greeting.

2

Add a Rubocop configuration variable

Create a variable called rubocop_config and set it to a string with this content: AllCops: TargetRubyVersion: 3.2

Ruby

def greet(name)
  puts "Hello, #{name}!"
end

# Create rubocop_config variable with TargetRubyVersion 3.2
# Your code here

Need a hint?

Use a string with newline \n to write the config content.

3

Run Rubocop linting using Ruby code

Write code to run Rubocop on example.rb using system and store the result in a variable called lint_result with this exact command: rubocop example.rb --config .rubocop.yml

Ruby

def greet(name)
  puts "Hello, #{name}!"
end

rubocop_config = "AllCops:\n  TargetRubyVersion: 3.2"

# Run Rubocop on example.rb and save output to lint_result
# Your code here

Need a hint?

Use backticks ` to run the shell command and capture output.

4

Print the Rubocop linting output

Write a puts statement to print the lint_result variable.

Ruby

def greet(name)
  puts "Hello, #{name}!"
end

rubocop_config = "AllCops:\n  TargetRubyVersion: 3.2"

lint_result = `rubocop example.rb --config .rubocop.yml`

# Print the lint_result output
# Your code here

Need a hint?

Use puts lint_result to show the Rubocop output in the console.