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Native characterset is wrong for unicode builds for Windows

9 messages · Duncan Murdoch, Winston Chang, maillist at tlink.de

Original
maillist at tlink.de
# 
When I send some outlandish characters through enc2native (or format) in 
R 3.1.2 on Ubuntu trusty it works quite well:

 > "?????"
[1] "?????"
 > enc2native("?????")
[1] "?????"
 > Encoding(enc2native("?????"))
[1] "UTF-8"

In Windows the result is different:

 > "?????"
[1] "?????"
 > enc2native("?????")
[1] "??<U+0394><U+040A><U+05EA>"
 > Encoding(enc2native("?????"))
[1] "latin1"

And this is wrong. The native character set of a unicode application 
under Windows is *Unicode*. enc2native should do the same under Windows 
as it does on Ubuntu. Also the "unknown" encoding should be changed to 
mean the same as "UTF-8" exactly as it is on Linux.
Duncan Murdoch
#
On 26/02/2015 3:09 PM, maillist at tlink.de wrote:
What is a "unicode application", and what makes you think R is one?  R
is being told by Windows that your native encoding is latin1.  Perhaps
Windows 8 supports UTF-8 as a native encoding (I've never used it), but
previous versions of Windows didn't.

Duncan Murdoch
Winston Chang
# 
On Thu, Feb 26, 2015 at 2:09 PM, maillist at tlink.de <maillist at tlink.de>
wrote:
I think you're mixing up the term "character set" with the encoding for a
character set. Unicode is a character set. UTF-8 is one of many encodings
of Unicode.

UTF-8 may be the native character encoding in Ubuntu, but it's not the
native encoding in Windows. According to this, what counts as the native
encoding in Windows depends on the code page:
  http://stackoverflow.com/a/4649507

So you shouldn't expect enc2native to do the same thing on Linux and
Windows. If you really want UTF-8, you can use enc2utf8.

-Winston
maillist at tlink.de
# 
A unicode application is a program that uses the unicode API of Windows 
- the functions with the ending W. For such a application the system 
code page (native encoding) is completely irrelevant. The system code 
page is just a compatibility feature that enables Windows NT/Vista/7/8 
to run applications that were developed for Windows 95 which didn't have 
unicode support. But this line of operating systems is dead for 10 years 
now. R obviously is a unicode application because it can print - or read 
from the clipboard - characters like "???" that are not in my system 
code page which is not possible over the legacy API.

Neither the unicode API nor the legacy API accepts UTF-8. The legacy API 
needs strings encoded according to the active code page and the unicode 
API wants UTF-16. If you have UTF-8 you need to convert it in either to 
the active code page which will loose all characters that are not 
covered by it or convert to UTF-16 and use the unicode functions. But 
this is not the problem, the Windows interface functions of R are 
working quite nicely with unicode already.
maillist at tlink.de
# 
Am 26.02.2015 um 23:44 schrieb Winston Chang:
Maybe I'm expecting too much but I rather have R not to produce garbage 
like "??<U+0394><U+040A><U+05EA>" and while I can use enc2utf8 to 
convert from UTF-8 to UTF-8 this does not fix the many places - like 
"format" - where enc2native is used and that are broken because of this.
Duncan Murdoch
#
On 26/02/2015 6:34 PM, maillist at tlink.de wrote:
R uses those functions, so I guess it is a "unicode application".  But
internally it uses an 8 bit encoding (normally the native one for the
platform it is running on, which in your case is apparently latin1).
Windows 95 had UCS-2 support, which was pretty close to UTF-16.

But this line of operating systems is dead for 10 years
So "unicode application" is something you just made up.

If you use Windows development tools, they have macros to convert
generic functions to either A or W versions.  R doesn't use those.  It
calls the W functions when it has UTF-16 characters, and A functions
when it has native characters.  I would love it if R was a UTF-8
application, because it would make life so much simpler, but Windows
doesn't support that.  So R needs to do tons of conversions.  If you
don't like that, you probably need to stick with Ubuntu.

Duncan Murdoch
maillist at tlink.de
# 
Am 27.02.2015 um 03:13 schrieb Duncan Murdoch:
I am not complaining about those conversions. They work just fine 
already. I am complaining about
enc2native breaking things in the windows builds. An assignment like

s <- format("?????")

has no interaction with windows at all yet "s" contains garbage like  
"??<U+0394><U+040A><U+05EA>"
after that. And if a native encoding of UTF-8 - as defined by enc2native 
- works in Ubuntu why shouldn't it work
in Windows?
Duncan Murdoch
#
On 27/02/2015 2:31 AM, maillist at tlink.de wrote:
Because in Ubuntu, UTF-8 is the native encoding, and in your Windows
system, latin1 is the native encoding.

But I do agree that the format() issue is a problem.  I haven't traced
through the code, but I think the string "?????" is read using Windows
API functions that return a UTF-16 result, then converted by R to UTF-8.
 So format() should see that it is a UTF-8 string and not convert it to
the native encoding.  There is nothing wrong with enc2native(), it's
doing what you asked for.  The problem is that format() is using it.

Duncan Murdoch
maillist at tlink.de
# 
Am 27.02.2015 um 11:49 schrieb Duncan Murdoch:
I would expect that every function that is using enc2native is broken in 
this respect because it invariably will scramble most unicode characters 
in the process and I can't think of a case where this could be wanted 
actually.
Functions that really need something other than UTF-8 are probably using 
iconv and getOption("encoding") anyway as this allows to specify the 
desired encoding much more flexible.