Class: RuboCop::Cop::Rails::PluckInWhere

Inherits:
RuboCop::Cop show all
Includes:
ActiveRecordHelper
Defined in:
lib/rubocop/cop/rails/pluck_in_where.rb

Overview

This cop identifies places where ‘pluck` is used in `where` query methods and can be replaced with `select`.

Since ‘pluck` is an eager method and hits the database immediately, using `select` helps to avoid additional database queries.

Examples:

# bad
Post.where(user_id: User.active.pluck(:id))

# good
Post.where(user_id: User.active.select(:id))

Constant Summary collapse

MSG = 
'Use `select` instead of `pluck` within `where` query method.'

Constants included from ActiveRecordHelper

ActiveRecordHelper::WHERE_METHODS

Instance Method Summary collapse

Methods included from ActiveRecordHelper

#external_dependency_checksum, #foreign_key_of, #in_where?, #resolve_relation_into_column, #schema, #table_name

Instance Method Details

#autocorrect(node) ⇒ Object 



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# File 'lib/rubocop/cop/rails/pluck_in_where.rb', line 28

def autocorrect(node)
  lambda do |corrector|
    corrector.replace(node.loc.selector, 'select')
  end
end

#on_send(node) ⇒ Object 



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# File 'lib/rubocop/cop/rails/pluck_in_where.rb', line 24

def on_send(node)
  add_offense(node, location: :selector) if node.method?(:pluck) && in_where?(node)
end