# frozen_string_literal: true require 'fast_spec_helper' require 'rubocop' require_relative '../../../../rubocop/cop/performance/ar_exists_and_present_blank.rb' RSpec.describe RuboCop::Cop::Performance::ARExistsAndPresentBlank do subject(:cop) { described_class.new } context 'when it is not haml file' do it 'does not flag it as an offense' do expect(subject).to receive(:in_haml_file?).with(anything).at_least(:once).and_return(false) expect_no_offenses <<~SOURCE return unless @users.exists? show @users if @users.present? SOURCE end end context 'when it is haml file' do before do expect(subject).to receive(:in_haml_file?).with(anything).at_least(:once).and_return(true) end context 'the same object uses exists? and present?' do it 'flags it as an offense' do expect_offense <<~SOURCE return unless @users.exists? show @users if @users.present? ^^^^^^^^^^^^^^^ Avoid `@users.present?`, because it will generate database query 'Select TABLE.*' which is expensive. Suggest to use `@users.any?` to replace `@users.present?` SOURCE end end context 'the same object uses exists? and blank?' do it 'flags it as an offense' do expect_offense <<~SOURCE return unless @users.exists? show @users if @users.blank? ^^^^^^^^^^^^^ Avoid `@users.blank?`, because it will generate database query 'Select TABLE.*' which is expensive. Suggest to use `@users.empty?` to replace `@users.blank?` SOURCE end end context 'the same object uses exists?, blank? and present?' do it 'flags it as an offense' do expect_offense <<~SOURCE return unless @users.exists? show @users if @users.blank? ^^^^^^^^^^^^^ Avoid `@users.blank?`, because it will generate database query 'Select TABLE.*' which is expensive. Suggest to use `@users.empty?` to replace `@users.blank?` show @users if @users.present? ^^^^^^^^^^^^^^^ Avoid `@users.present?`, because it will generate database query 'Select TABLE.*' which is expensive. Suggest to use `@users.any?` to replace `@users.present?` SOURCE end end RSpec.shared_examples 'different object uses exists? and present?/blank?' do |another_method| it 'does not flag it as an offense' do expect_no_offenses <<~SOURCE return unless @users.exists? present @emails if @emails.#{another_method} SOURCE end end it_behaves_like 'different object uses exists? and present?/blank?', 'present?' it_behaves_like 'different object uses exists? and present?/blank?', 'blank?' RSpec.shared_examples 'Only using one present?/blank? without exists?' do |non_exists_method| it 'does not flag it as an offense' do expect_no_offenses "@users.#{non_exists_method}" end end it_behaves_like 'Only using one present?/blank? without exists?', 'present?' it_behaves_like 'Only using one present?/blank? without exists?', 'blank?' context 'when using many present?/empty? without exists?' do it 'does not flag it as an offense' do expect_no_offenses <<~SOURCE @user.present? @user.blank? @user.present? @user.blank? SOURCE end end context 'when just using exists? without present?/blank?' do it 'does not flag it as an offense' do expect_no_offenses '@users.exists?' expect_no_offenses <<~SOURCE @users.exists? @users.some_other_method? @users.exists? SOURCE end end end end