Ruby Development

Name: Ruby Development
Rating: 62
Author: channingwalton

Principles

•Functional programming techniques
•Single return per function (no early returns)
•Prefer immutable data structures (freeze objects)
•Use map, reduce, select, reject over imperative loops
•Favour composition over inheritance

Testing

Use project's existing test framework. Test structure follows AAA pattern:

ruby

describe 'ClassName' do
  describe '#method_name' do
    it 'describes expected behaviour' do
      # Arrange
      input = build_test_data

      # Act
      result = subject.method_name(input)

      # Assert
      expect(result).to eq(expected)
    end
  end
end

Run tests:

bash

bundle exec rspec           # RSpec
bundle exec rake test       # Minitest

Linting

bash

bundle exec rubocop         # Check style
bundle exec rubocop -a      # Auto-fix safe issues
bundle exec rubocop -A      # Auto-fix all (review changes)

Functional Patterns

Transform with map:

ruby

# ❌ Imperative
results = []
items.each { |i| results << transform(i) }

# ✅ Functional
results = items.map { |i| transform(i) }

Filter with select/reject:

ruby

valid_items = items.select(&:valid?)
invalid_items = items.reject(&:valid?)

Reduce for accumulation:

ruby

total = items.reduce(0) { |sum, item| sum + item.value }

Chain operations:

ruby

items
  .select(&:active?)
  .map(&:transform)
  .reduce(initial) { |acc, x| combine(acc, x) }

Immutability:

ruby

CONSTANTS = ['a', 'b', 'c'].freeze
hash = { key: 'value' }.freeze