k0kubun	2018-03-13 21:56:04 +0900 (Tue, 13 Mar 2018)

  New Revision: 62743

  https://svn.ruby-lang.org/cgi-bin/viewvc.cgi?view=revision&revision=62743

  Log:
    Fix FrozenError on `Ripper.slice`
    
    Currently `Ripper.slice` raises a FrozenError
    
    ```ruby
    require 'ripper'
    p Ripper.slice('foo', 'ident')
    ```
    
    ```
    /path/to/g/lib/ruby/2.6.0/ripper/lexer.rb:193:in `concat': can't modify frozen String (FrozenError)
    from /path/to/g/lib/ruby/2.6.0/ripper/lexer.rb:193:in `block in compile'
    from /path/to/g/lib/ruby/2.6.0/ripper/lexer.rb:190:in `scan'
    from /path/to/g/lib/ruby/2.6.0/ripper/lexer.rb:190:in `compile'
    from /path/to/g/lib/ruby/2.6.0/ripper/lexer.rb:169:in `initialize'
    from /path/to/g/lib/ruby/2.6.0/ripper/lexer.rb:151:in `new'
    from /path/to/g/lib/ruby/2.6.0/ripper/lexer.rb:151:in `token_match'
    from /path/to/g/lib/ruby/2.6.0/ripper/lexer.rb:144:in `slice'
    from /tmp/tmp.kb4cnhvum2/test.rb:2:in `<main>'
    ```
    
    This patch will fix the problem.
    
    [Fix GH-1837]
    
    From: Masataka Pocke Kuwabara <kuwabara@p...>

  Modified files:
    trunk/ext/ripper/lib/ripper/lexer.rb
Index: ext/ripper/lib/ripper/lexer.rb
===================================================================
--- ext/ripper/lib/ripper/lexer.rb	(revision 62742)
+++ ext/ripper/lib/ripper/lexer.rb	(revision 62743)
@@ -186,7 +186,7 @@ class Ripper https://github.com/ruby/ruby/blob/trunk/ext/ripper/lib/ripper/lexer.rb#L186
       if m = /[^\w\s$()\[\]{}?*+\.]/.match(pattern)
         raise CompileError, "invalid char in pattern: #{m[0].inspect}"
       end
-      buf = ''
+      buf = +''
       pattern.scan(/(?:\w+|\$\(|[()\[\]\{\}?*+\.]+)/) do |tok|
         case tok
         when /\w/

--
ML: ruby-changes@q...
Info: http://www.atdot.net/~ko1/quickml/