thoughtbot/paperclip

This cop checks hash literal syntax.

It can enforce either the use of the class hash rocket syntax or the use of the newer Ruby 1.9 syntax (when applicable).

A separate offense is registered for each problematic pair.

The supported styles are:

• ruby19 - forces use of the 1.9 syntax (e.g. {a: 1}) when hashes have all symbols for keys
• hash_rockets - forces use of hash rockets for all hashes
• nomixedkeys - simply checks for hashes with mixed syntaxes
• ruby19nomixed_keys - forces use of ruby 1.9 syntax and forbids mixed syntax hashes

Example: EnforcedStyle: ruby19 (default)

# bad
{:a => 2}
{b: 1, :c => 2}

# good
{a: 2, b: 1}
{:c => 2, 'd' => 2} # acceptable since 'd' isn't a symbol
{d: 1, 'e' => 2} # technically not forbidden

Example: EnforcedStyle: hash_rockets

# bad
{a: 1, b: 2}
{c: 1, 'd' => 5}

# good
{:a => 1, :b => 2}

Example: EnforcedStyle: nomixedkeys

# bad
{:a => 1, b: 2}
{c: 1, 'd' => 2}

# good
{:a => 1, :b => 2}
{c: 1, d: 2}

Example: EnforcedStyle: ruby19nomixed_keys

# bad
{:a => 1, :b => 2}
{c: 2, 'd' => 3} # should just use hash rockets

# good
{a: 1, b: 2}
{:c => 3, 'd' => 4}

Checks if uses of quotes match the configured preference.

Example: EnforcedStyle: single_quotes (default)

# bad
"No special symbols"
"No string interpolation"
"Just text"

# good
'No special symbols'
'No string interpolation'
'Just text'
"Wait! What's #{this}!"

Example: EnforcedStyle: double_quotes

# bad
'Just some text'
'No special chars or interpolation'

# good
"Just some text"
"No special chars or interpolation"
"Every string in #{project} uses double_quotes"

Checks if uses of quotes match the configured preference.

Example: EnforcedStyle: single_quotes (default)

# bad
"No special symbols"
"No string interpolation"
"Just text"

# good
'No special symbols'
'No string interpolation'
'Just text'
"Wait! What's #{this}!"

Example: EnforcedStyle: double_quotes

# bad
'Just some text'
'No special chars or interpolation'

# good
"Just some text"
"No special chars or interpolation"
"Every string in #{project} uses double_quotes"

This cops checks if empty lines around the bodies of classes match the configuration.

Example: EnforcedStyle: empty_lines

# good

class Foo

  def bar
    # ...
  end

end

Example: EnforcedStyle: emptylinesexcept_namespace

# good

class Foo
  class Bar

    # ...

  end
end

Example: EnforcedStyle: emptylinesspecial

# good
class Foo

  def bar; end

end

Example: EnforcedStyle: noemptylines (default)

# good

class Foo
  def bar
    # ...
  end
end

Checks that block braces have or don't have surrounding space inside them on configuration. For blocks taking parameters, it checks that the left brace has or doesn't have trailing space depending on configuration.

Example: EnforcedStyle: space (default)

# The `space` style enforces that block braces have
# surrounding space.

# bad
some_array.each {puts e}

# good
some_array.each { puts e }

Example: EnforcedStyle: no_space

# The `no_space` style enforces that block braces don't
# have surrounding space.

# bad
some_array.each { puts e }

# good
some_array.each {puts e}

Example: EnforcedStyleForEmptyBraces: no_space (default)

# The `no_space` EnforcedStyleForEmptyBraces style enforces that
# block braces don't have a space in between when empty.

# bad
some_array.each {   }
some_array.each {  }
some_array.each { }

# good
some_array.each {}

Example: EnforcedStyleForEmptyBraces: space

# The `space` EnforcedStyleForEmptyBraces style enforces that
# block braces have at least a spece in between when empty.

# bad
some_array.each {}

# good
some_array.each { }
some_array.each {  }
some_array.each {   }

Example: SpaceBeforeBlockParameters: true (default)

# The SpaceBeforeBlockParameters style set to `true` enforces that
# there is a space between `{` and `|`. Overrides `EnforcedStyle`
# if there is a conflict.

# bad
[1, 2, 3].each {|n| n * 2 }

# good
[1, 2, 3].each { |n| n * 2 }

Example: SpaceBeforeBlockParameters: true

# The SpaceBeforeBlockParameters style set to `false` enforces that
# there is no space between `{` and `|`. Overrides `EnforcedStyle`
# if there is a conflict.

# bad
[1, 2, 3].each { |n| n * 2 }

# good
[1, 2, 3].each {|n| n * 2 }

This cop checks for unused method arguments.

Example:

# bad

def some_method(used, unused, _unused_but_allowed)
  puts used
end

Example:

# good

def some_method(used, _unused, _unused_but_allowed)
  puts used
end

This cop checks for unused method arguments.

Example:

# bad

def some_method(used, unused, _unused_but_allowed)
  puts used
end

Example:

# good

def some_method(used, _unused, _unused_but_allowed)
  puts used
end

This cops checks for parentheses around the arguments in method definitions. Both instance and class/singleton methods are checked.

Example: EnforcedStyle: require_parentheses (default)

# The `require_parentheses` style requires method definitions
# to always use parentheses

# bad
def bar num1, num2
  num1 + num2
end

def foo descriptive_var_name,
        another_descriptive_var_name,
        last_descriptive_var_name
  do_something
end

# good
def bar(num1, num2)
  num1 + num2
end

def foo(descriptive_var_name,
        another_descriptive_var_name,
        last_descriptive_var_name)
  do_something
end

Example: EnforcedStyle: requirenoparentheses

# The `require_no_parentheses` style requires method definitions
# to never use parentheses

# bad
def bar(num1, num2)
  num1 + num2
end

def foo(descriptive_var_name,
        another_descriptive_var_name,
        last_descriptive_var_name)
  do_something
end

# good
def bar num1, num2
  num1 + num2
end

def foo descriptive_var_name,
        another_descriptive_var_name,
        last_descriptive_var_name
  do_something
end

Example: EnforcedStyle: requirenoparenthesesexceptmultiline

# The `require_no_parentheses_except_multiline` style prefers no
# parantheses when method definition arguments fit on single line,
# but prefers parantheses when arguments span multiple lines.

# bad
def bar(num1, num2)
  num1 + num2
end

def foo descriptive_var_name,
        another_descriptive_var_name,
        last_descriptive_var_name
  do_something
end

# good
def bar num1, num2
  num1 + num2
end

def foo(descriptive_var_name,
        another_descriptive_var_name,
        last_descriptive_var_name)
  do_something
end

This cop checks whether some constant value isn't a mutable literal (e.g. array or hash).

Example:

# bad
CONST = [1, 2, 3]

# good
CONST = [1, 2, 3].freeze

This cop checks for unused block arguments.

Example:

# bad

do_something do |used, unused|
  puts used
end

do_something do |bar|
  puts :foo
end

define_method(:foo) do |bar|
  puts :baz
end

Example:

#good

do_something do |used, _unused|
  puts used
end

do_something do
  puts :foo
end

define_method(:foo) do |_bar|
  puts :baz
end

Checks for empty else-clauses, possibly including comments and/or an explicit nil depending on the EnforcedStyle.

Example: EnforcedStyle: empty

# warn only on empty else

# bad
if condition
  statement
else
end

# good
if condition
  statement
else
  nil
end

# good
if condition
  statement
else
  statement
end

# good
if condition
  statement
end

Example: EnforcedStyle: nil

# warn on else with nil in it

# bad
if condition
  statement
else
  nil
end

# good
if condition
  statement
else
end

# good
if condition
  statement
else
  statement
end

# good
if condition
  statement
end

Example: EnforcedStyle: both (default)

# warn on empty else and else with nil in it

# bad
if condition
  statement
else
  nil
end

# bad
if condition
  statement
else
end

# good
if condition
  statement
else
  statement
end

# good
if condition
  statement
end

This cop checks hash literal syntax.

It can enforce either the use of the class hash rocket syntax or the use of the newer Ruby 1.9 syntax (when applicable).

A separate offense is registered for each problematic pair.

The supported styles are:

• ruby19 - forces use of the 1.9 syntax (e.g. {a: 1}) when hashes have all symbols for keys
• hash_rockets - forces use of hash rockets for all hashes
• nomixedkeys - simply checks for hashes with mixed syntaxes
• ruby19nomixed_keys - forces use of ruby 1.9 syntax and forbids mixed syntax hashes

Example: EnforcedStyle: ruby19 (default)

# bad
{:a => 2}
{b: 1, :c => 2}

# good
{a: 2, b: 1}
{:c => 2, 'd' => 2} # acceptable since 'd' isn't a symbol
{d: 1, 'e' => 2} # technically not forbidden

Example: EnforcedStyle: hash_rockets

# bad
{a: 1, b: 2}
{c: 1, 'd' => 5}

# good
{:a => 1, :b => 2}

Example: EnforcedStyle: nomixedkeys

# bad
{:a => 1, b: 2}
{c: 1, 'd' => 2}

# good
{:a => 1, :b => 2}
{c: 1, d: 2}

Example: EnforcedStyle: ruby19nomixed_keys

# bad
{:a => 1, :b => 2}
{c: 2, 'd' => 3} # should just use hash rockets

# good
{a: 1, b: 2}
{:c => 3, 'd' => 4}