Class: RuboCop::Cop::Rails::FindBy

Inherits:
Base
  • Object
show all
Extended by:
AutoCorrector
Includes:
RangeHelp
Defined in:
lib/rubocop/cop/rails/find_by.rb

Overview

Identifies usages of where.take and change them to use find_by instead.

And where(...).first can return different results from find_by. (They order records differently, so the "first" record can be different.)

If you also want to detect where.first, you can set IgnoreWhereFirst to false.

Examples:

# bad
User.where(name: 'Bruce').take

# good
User.find_by(name: 'Bruce')

IgnoreWhereFirst: true (default)

# good
User.where(name: 'Bruce').first

IgnoreWhereFirst: false

# bad
User.where(name: 'Bruce').first

Constant Summary collapse

MSG = 
'Use `find_by` instead of `where%<dot>s%<method>s`.'
RESTRICT_ON_SEND = 
%i[first take].freeze

Instance Method Summary collapse

Instance Method Details

#on_send(node) ⇒ Object Also known as: on_csend 



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# File 'lib/rubocop/cop/rails/find_by.rb', line 34

def on_send(node)
  return unless node.arguments.empty? && where_method?(node.receiver)
  return if ignore_where_first? && node.method?(:first)

  range = offense_range(node)

  add_offense(range, message: format(MSG, dot: node.loc.dot.source, method: node.method_name)) do |corrector|
    autocorrect(corrector, node)
  end
end