Class: RuboCop::Cop::Style::Alias

Inherits:
Base
  • Object
show all
Extended by:
AutoCorrector
Includes:
ConfigurableEnforcedStyle
Defined in:
lib/rubocop/cop/style/alias.rb

Overview

Enforces the use of either ‘#alias` or `#alias_method` depending on configuration. It also flags uses of `alias :symbol` rather than `alias bareword`.

However, it will always enforce ‘method_alias` when used `alias` in an instance method definition and in a singleton method definition. If used in a block, always enforce `alias_method` unless it is an `instance_eval` block.

Examples:

EnforcedStyle: prefer_alias (default)

# bad
alias_method :bar, :foo
alias :bar :foo

# good
alias bar foo

EnforcedStyle: prefer_alias_method

# bad
alias :bar :foo
alias bar foo

# good
alias_method :bar, :foo

Constant Summary collapse

MSG_ALIAS = 
'Use `alias_method` instead of `alias`.'
MSG_ALIAS_METHOD = 
'Use `alias` instead of `alias_method` %<current>s.'
MSG_SYMBOL_ARGS = 
'Use `alias %<prefer>s` instead of `alias %<current>s`.'
RESTRICT_ON_SEND = 
%i[alias_method].freeze

Instance Method Summary collapse

Methods included from AutoCorrector

support_autocorrect?

Methods included from ConfigurableEnforcedStyle

#alternative_style, #alternative_styles, #ambiguous_style_detected, #correct_style_detected, #detected_style, #detected_style=, #no_acceptable_style!, #no_acceptable_style?, #opposite_style_detected, #style, #style_configured?, #style_detected, #style_parameter_name, #supported_styles, #unexpected_style_detected

Instance Method Details

#on_alias(node) ⇒ Object 



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# File 'lib/rubocop/cop/style/alias.rb', line 52

def on_alias(node)
  return unless alias_method_possible?(node)

  if scope_type(node) == :dynamic || style == :prefer_alias_method
    add_offense(node.loc.keyword, message: MSG_ALIAS) do |corrector|
      autocorrect(corrector, node)
    end
  elsif node.children.none? { |arg| bareword?(arg) }
    add_offense_for_args(node) { |corrector| autocorrect(corrector, node) }
  end
end

#on_send(node) ⇒ Object 



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# File 'lib/rubocop/cop/style/alias.rb', line 41

def on_send(node)
  return unless node.command?(:alias_method)
  return unless style == :prefer_alias && alias_keyword_possible?(node)
  return unless node.arguments.count == 2

  msg = format(MSG_ALIAS_METHOD, current: lexical_scope_type(node))
  add_offense(node.loc.selector, message: msg) do |corrector|
    autocorrect(corrector, node)
  end
end