Module#attr_setter does not support frozen-string-literal #286
Description
I got the "can't modify frozen String" error when I use the --enable-frozen-string-literal Ruby option.
It is because that Module#attr_setter method does not support frozen-string-literal.
You can see the same error by running commands below
$ export RUBYOPT='--enable-frozen-string-literal'
$ ruby-test test/core/module/test_attr_setter.rb
Then, you will see the error message below
can't modify frozen String
C:/Users/ishitani/workspace/facets/lib/core/facets/module/attr_setter.rb:24
22 code, made = '', []
23 args.each do |a|
=> 24 code << %{
25 def #{a}(*args)
26 args.size > 0 ? ( @#{a}=args[0] ; self ) : @#{a}
C:/Users/ishitani/workspace/facets/lib/core/facets/module/attr_setter.rb:24
C:/Users/ishitani/workspace/facets/lib/core/facets/module/attr_setter.rb:23
test/core/module/test_attr_setter.rb:9
test/core/module/test_attr_setter.rb:8
C:/Ruby/Ruby25-x64/lib/ruby/gems/2.5.0/gems/rubytest-cli-0.2.0/lib/rubytest-cli.rb:48
C:/Ruby/Ruby25-x64/lib/ruby/gems/2.5.0/gems/rubytest-cli-0.2.0/lib/rubytest-cli.rb:18
C:/Ruby/Ruby25-x64/lib/ruby/gems/2.5.0/gems/rubytest-cli-0.2.0/bin/ruby-test:4
C:/Ruby/Ruby25-x64/bin/ruby-test:23