From 1b86d90136efb98c7b331a84ca163587307a49af Mon Sep 17 00:00:00 2001 From: "yuuji.yaginuma" Date: Thu, 17 May 2018 17:32:27 +0900 Subject: Enable `Performance/UnfreezeString` cop MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit In Ruby 2.3 or later, `String#+@` is available and `+@` is faster than `dup`. ```ruby # frozen_string_literal: true require "bundler/inline" gemfile(true) do source "https://rubygems.org" gem "benchmark-ips" end Benchmark.ips do |x| x.report('+@') { +"" } x.report('dup') { "".dup } x.compare! end ``` ``` $ ruby -v benchmark.rb ruby 2.5.1p57 (2018-03-29 revision 63029) [x86_64-linux] Warming up -------------------------------------- +@ 282.289k i/100ms dup 187.638k i/100ms Calculating ------------------------------------- +@ 6.775M (± 3.6%) i/s - 33.875M in 5.006253s dup 3.320M (± 2.2%) i/s - 16.700M in 5.032125s Comparison: +@: 6775299.3 i/s dup: 3320400.7 i/s - 2.04x slower ``` --- .../active_record/connection_adapters/abstract/schema_creation.rb | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'activerecord/lib/active_record/connection_adapters/abstract/schema_creation.rb') diff --git a/activerecord/lib/active_record/connection_adapters/abstract/schema_creation.rb b/activerecord/lib/active_record/connection_adapters/abstract/schema_creation.rb index 529c9d8ca6..9d9e8a4110 100644 --- a/activerecord/lib/active_record/connection_adapters/abstract/schema_creation.rb +++ b/activerecord/lib/active_record/connection_adapters/abstract/schema_creation.rb @@ -21,7 +21,7 @@ module ActiveRecord private def visit_AlterTable(o) - sql = "ALTER TABLE #{quote_table_name(o.name)} ".dup + sql = +"ALTER TABLE #{quote_table_name(o.name)} " sql << o.adds.map { |col| accept col }.join(" ") sql << o.foreign_key_adds.map { |fk| visit_AddForeignKey fk }.join(" ") sql << o.foreign_key_drops.map { |fk| visit_DropForeignKey fk }.join(" ") @@ -29,17 +29,17 @@ module ActiveRecord def visit_ColumnDefinition(o) o.sql_type = type_to_sql(o.type, o.options) - column_sql = "#{quote_column_name(o.name)} #{o.sql_type}".dup + column_sql = +"#{quote_column_name(o.name)} #{o.sql_type}" add_column_options!(column_sql, column_options(o)) unless o.type == :primary_key column_sql end def visit_AddColumnDefinition(o) - "ADD #{accept(o.column)}".dup + +"ADD #{accept(o.column)}" end def visit_TableDefinition(o) - create_sql = "CREATE#{' TEMPORARY' if o.temporary} TABLE #{quote_table_name(o.name)} ".dup + create_sql = +"CREATE#{' TEMPORARY' if o.temporary} TABLE #{quote_table_name(o.name)} " statements = o.columns.map { |c| accept c } statements << accept(o.primary_keys) if o.primary_keys -- cgit v1.2.3