Class: Rubocop::Cop::Style::Lambda

Inherits:
Cop
  • Object
show all
Defined in:
lib/rubocop/cop/style/lambda.rb

Overview

This cop checks for uses of the pre 1.9 lambda syntax for one-line anonymous functions and uses of the 1.9 lambda syntax for multi-line anonymous functions.

Constant Summary collapse

SINGLE_MSG = 
'Use the new lambda literal syntax ->(params) {...}.'
MULTI_MSG = 
'Use the lambda method for multi-line lambdas.'
TARGET = 
s(:send, nil, :lambda)

Constants inherited from Cop

Cop::OPERATOR_METHODS

Instance Attribute Summary

Attributes inherited from Cop

#config, #corrections, #offences, #processed_source

Instance Method Summary collapse

Methods inherited from Cop

#add_offence, all, #autocorrect?, #convention, #cop_config, cop_name, #cop_name, cop_type, #debug?, #ignore_node, inherited, #initialize, lint?, #message, non_rails, rails?, style?, #support_autocorrect?, #warning

Constructor Details

This class inherits a constructor from Rubocop::Cop::Cop

Instance Method Details

#on_block(node) ⇒ Object 



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# File 'lib/rubocop/cop/style/lambda.rb', line 15

def on_block(node)
  # We're looking for
  # (block
  #   (send nil :lambda)
  #   ...)
  block_method, = *node

  if block_method == TARGET
    selector = block_method.loc.selector.source
    lambda_length = lambda_length(node)

    if selector != '->' && lambda_length == 0
      convention(block_method, :expression, SINGLE_MSG)
    elsif selector == '->' && lambda_length > 0
      convention(block_method, :expression, MULTI_MSG)
    end
  end
end