string encoding is incorrect when compiling to .class files via jrubyc #4445
Description
Environment
user@ ~/dev/jruby (master)$ jruby -v
jruby 9.1.5.0 (2.3.1) 2016-09-07 036ce39 Java HotSpot(TM) 64-Bit Server VM 25.112-b16 on 1.8.0_112-b16 +jit [darwin-x86_64]
user@ ~/dev/jruby (master)$ uname -a
Darwin computer_name 16.3.0 Darwin Kernel Version 16.3.0: Thu Nov 17 20:23:58 PST 2016; root:xnu-3789.31.2~1/RELEASE_X86_64 x86_64
Expected Behavior
I expect the default encoding of a string in ruby 2.x compatible jruby to be UTF-8 and not ASCII-8BIT when no encoding is specified in the source file header.
Actual Behavior
user@ ~/dev$ rvm use jruby-9.1.5.0
Using /Users/user/.rvm/gems/jruby-9.1.5.0
user@ ~/dev$ cat enc_test.rb
puts ''.encoding
user@ ~/dev$ jrubyc enc_test.rb
user@ ~/dev$ java -cp .:/Users/user/.rvm/rubies/jruby-9.1.5.0/lib/jruby.jar enc_test
ASCII-8BIT
user@ ~/dev$ jruby enc_test.rb
UTF-8
Notice how the default encoding of the empty string that is declared when run from the .class file generated by jrubyc is ASCII-8BIT, but when run via jruby it is UTF-8.
The docs here indicate:
All Ruby script code has an associated Encoding which any String literal created in the source code will be associated to.
The default script encoding is Encoding::UTF-8 after v2.0...
jruby 9.1.6.0 seems to also suffer from the same problem:
user@ ~/dev$ rvm use jruby-9.1.6.0
Using /Users/user/.rvm/gems/jruby-9.1.6.0
user@ ~/dev$ jrubyc enc_test.rb
user@ ~/dev$ java -cp .:/Users/user/.rvm/rubies/jruby-9.1.6.0/lib/jruby.jar enc_test
ASCII-8BIT
user@ ~/dev$ jruby enc_test.rb
UTF-8
jruby 9.1.7.0 looks to have a separate problem that prevents even this simple example from running:
user@ ~/dev$ rvm use jruby-9.1.7.0
Using /Users/user/.rvm/gems/jruby-9.1.7.0
user@ ~/dev$ jrubyc enc_test.rb
TypeError: failed to coerce org.objectweb.asm.ClassWriter to org.jruby.org.objectweb.asm.ClassVisitor
block in compile_files_with_options at /Users/user/.rvm/rubies/jruby-9.1.7.0/lib/ruby/stdlib/jruby/compiler.rb:189
block in compile_files_with_options at /Users/user/.rvm/rubies/jruby-9.1.7.0/lib/ruby/stdlib/jruby/compiler.rb:297
each at org/jruby/RubyArray.java:1733
compile_files_with_options at /Users/user/.rvm/rubies/jruby-9.1.7.0/lib/ruby/stdlib/jruby/compiler.rb:281
compile_argv at /Users/user/.rvm/rubies/jruby-9.1.7.0/lib/ruby/stdlib/jruby/compiler.rb:94
<main> at /Users/user/.rvm/rubies/jruby-9.1.7.0/bin/jrubyc:5
user@ ~/dev$ jruby enc_test.rb
UTF-8