Unicode javascript strings are not transferred to ruby
correctly. Here's an example. I create a javascript string
consisting of a single Euro-Sign (see http://www.fileformat.info/info/unicode/char/20ac/index.htm)
irb(main):001:0> require 'rubygems'
=> true
irb(main):002:0> require 'johnson'
=> true
irb(main):007:0> s = Johnson.evaluate("'\\u20AC'")
=> "\254"
In ruby, we're getting a single byte with the value 254 (octal),
which is 172 decimal, or 0xAC. So it looks like we're only getting
the low-byte of our 16-bit Unicode char. After scanning the Johnson
code, I think I found the culprit - JS_GetStringBytes returns the bytes
of a Unicode-16 String by stripping off the
high-bytes.
Note that for non-ASCII strings, if JS_CStringsAreUTF8 is false,
these functions can return a corrupted copy of the contents of
>the string. Use JS_GetStringChars to access the 16-bit
characters of a JavaScript string without conversions or
copying.
A similar problem probably exists in the other direction (ruby
-> js) too.
I suggest trying JS_CStringsAreUTF8 (which may solve both
problems). If this fails, then johnson would have to extract the
Unicode-16 chars from spidermonkey and convert them to a
ruby-friendly encoding.
