46 lines
1.2 KiB
Ruby
46 lines
1.2 KiB
Ruby
|
# frozen_string_literal: true
|
||
|
|
|
||
|
|
module RuboCop
|
||
|
|
module Cop
|
||
|
|
module Performance
|
||
|
|
class ARCountEach < RuboCop::Cop::Cop
|
||
|
|
def message(ivar)
|
||
|
|
"If #{ivar} is AR relation, avoid `#{ivar}.count ...; #{ivar}.each... `, this will trigger two queries. " \
|
||
|
|
"Use `#{ivar}.load.size ...; #{ivar}.each... ` instead. If #{ivar} is an array, try to use #{ivar}.size."
|
||
|
|
end
|
||
|
|
|
||
|
|
def_node_matcher :count_match, <<~PATTERN
|
||
|
|
(send (ivar $_) :count)
|
||
|
|
PATTERN
|
||
|
|
|
||
|
|
def_node_matcher :each_match, <<~PATTERN
|
||
|
|
(send (ivar $_) :each)
|
||
|
|
PATTERN
|
||
|
|
|
||
|
|
def file_name(node)
|
||
|
|
node.location.expression.source_buffer.name
|
||
|
|
end
|
||
|
|
|
||
|
|
def in_haml_file?(node)
|
||
|
|
file_name(node).end_with?('.haml.rb')
|
||
|
|
end
|
||
|
|
|
||
|
|
def on_send(node)
|
||
|
|
return unless in_haml_file?(node)
|
||
|
|
|
||
|
|
ivar_count = count_match(node)
|
||
|
|
return unless ivar_count
|
||
|
|
|
||
|
|
node.each_ancestor(:begin) do |begin_node|
|
||
|
|
begin_node.each_descendant do |n|
|
||
|
|
ivar_each = each_match(n)
|
||
|
|
|
||
|
|
add_offense(node, location: :expression, message: message(ivar_count)) if ivar_each == ivar_count
|
||
|
|
end
|
||
|
|
end
|
||
|
|
end
|
||
|
|
end
|
||
|
|
end
|
||
|
|
end
|
||
|
|
end
|