ruby.md

Ruby Style Guide

Borrowed heavily from the Github Ruby Styleguide.

Basic formatting

• Use 2 space indentation (no hard tabs)
• No trailing whitespace
• Avoid exceeding 80 characters per line

Strings

• Use single quotes, unless you need interpolation.

  "foobar" # bad
  'foobar' # good

• When using string intepolation, don't use spaces before/after { and }.

  "foo{ bar }" # bad
  "foo{bar}"   # good

• Use double quotes if the string contains single quotes.

  'Don\'t use single quotes here' # bad
  "Don't use single quotes here"  # good

Arrays and hashes

• Use Ruby 1.9 hash syntax.

  numbers = { 'one' => 1, 'two' => 2, 'three' => 3 }     # bad
  numbers = { one: 1, two: 2, three: 3 }                 # good

• Use literal array syntax for arrays of strings.

  STATES = ['new', 'approved', 'rejected'] # bad
  STATES = %w(new approved rejected)       # good

Conditions

• Leave blank lines between if blocks.

  # Bad
  if some_condition?
    do_something
  if some_other_condition?
    do_something_else
  
  # Good
  if some_condition?
    do_something
  
  if some_other_condition?
    do_something_else

• Use unless condition? instead of if !condition?.

• Never use unless-else conditions. Replace it with if-else.

  # Bad
  unless success?
    puts 'failure'
  else
    puts 'success'
  end
  
  # Good
  if success?
    puts 'success'
  else
    puts 'failure'
  end

Blocks

• Use { ... } blocks instead of single line do ... end blocks.

  # Bad
  manipulate! do |img|
    img.auto_orient!
  end
  
  # Good
  manipulate! { |img| img.auto_orient! }

Methods

• Use parentheses around arguments in method definition.

  def foo bar   # bad
  def foo(bar)  # good

• Don't use parentheses when there are no arguments.

  def foo()   # bad
  def foo     # good

• Always use parentheses in method calls when there is a condition after it.

  foo(bar) if baz?  # good
  foo bar if baz?   # bad