Backport #8143: [patch] forwardable: reduce allocations in def_delegators wrappers

• Status: Rejected
• Assignee: nagachika (Tomoyuki Chikanaga)

[tmm1 (Aman Karmani)]

$ ./ruby -Ilib -rpp -rforwardable -e '
module Test
extend Forwardable
def_delegators :@test, *("a".."z")
end

GC.start
strings = ObjectSpace.each_object(String).select{ |s| s.frozen? && s =~ /forwardable/ }
p strings.size
pp strings.inject(Hash.new 0){ |h,s| h[s]+=1; h }
'

before:

73
[["/Users/test/code/ruby\\-trunk/lib/forwardable\\.rb", 26],
 ["/Users/test/code/ruby-trunk/lib/forwardable.rb", 33]]

after:

46
[["/Users/test/code/ruby-trunk/lib/forwardable.rb", 31],
 ["/Users/test/code/ruby-trunk/lib/forwardable", 1]]

diff --git a/lib/forwardable.rb b/lib/forwardable.rb
index d7116ed..2bd67f6 100644
--- a/lib/forwardable.rb
+++ b/lib/forwardable.rb
@@ -102,6 +102,7 @@ module Forwardable

Version of +forwardable.rb+

FORWARDABLE_VERSION = "1.1.0"

• FILE_REGEXP = %r"#{Regexp.quote(FILE)}"o
  @debug = nil
  class << self

  If true, FILE will remain in the backtrace in the event an

@@ -170,7 +171,7 @@ module Forwardable
begin
#{accessor}.send(:#{method}, *args, &block)
rescue Exception

•      $@.delete_if{|s| %r"#{Regexp.quote(__FILE__)}"o =~ s} unless Forwardable::debug
  

•      $@.delete_if{|s| Forwardable::FILE_REGEXP =~ s} unless Forwardable::debug
       ::Kernel::raise
     end
   end
  

@@ -262,7 +263,7 @@ module SingleForwardable
begin
#{accessor}.send(:#{method}, *args, &block)
rescue Exception

•      $@.delete_if{|s| %r"#{Regexp.quote(__FILE__)}"o =~ s} unless Forwardable::debug
  

•      $@.delete_if{|s| Forwardable::FILE_REGEXP =~ s} unless Forwardable::debug
       ::Kernel::raise
     end
   end
  

[nobu (Nobuyoshi Nakada)]

• Status changed from Open to Closed
• % Done changed from 0 to 100

This issue was solved with changeset r39875.
Aman, thank you for reporting this issue.
Your contribution to Ruby is greatly appreciated.
May Ruby be with you.

---

forwardable.rb: reduce allocations in def_delegators

• lib/forwardable.rb (Forwardable::FILE_REGEXP): create regexp object
  outside sources for eval, to reduce allocations in def_delegators
  wrappers. //o option does not make each regexps shared. patch by
  tmm1 (Aman Gupta) in [ruby-core:53620] [Bug #8143].

[tmm1 (Aman Karmani)]

• Tracker changed from Bug to Backport
• Project changed from Ruby master to Backport200
• Status changed from Closed to Open

[tmm1 (Aman Karmani)]

• Status changed from Open to Assigned
• Assignee set to nagachika (Tomoyuki Chikanaga)
• % Done changed from 100 to 0

[naruse (Yui NARUSE)]

• Status changed from Assigned to Rejected