Re: git on MacOSX and files with decomposed utf-8 file names

[Wincent Colaiuta <win@wincent.com>]

El 16/1/2008, a las 16:43, Kevin Ballard escribió:

> On Jan 16, 2008, at 10:34 AM, Johannes Schindelin wrote:
>
>> On Wed, 16 Jan 2008, Mark Junker wrote:
>>
>>> I have some files like "Lüftung.txt" in my repository. The strange  
>>> thing is
>>> that I can pull / add / commit / push those files without problem  
>>> but
>>> git-status always complains that thoes files are untraced (but not  
>>> missing).
>>
>> This is a known problem.  Unfortunately, noone has implemented a fix,
>> although if you're serious about it, I can point you to threads  
>> where it
>> has been hinted how to solve the issue.
>>
>> FWIW the issue is that Mac OS X decides that it knows better how to  
>> encode
>> your filename than you could yourself.
>
> More like, Mac OS X has standardized on Unicode and the rest of the  
> world hasn't caught up yet. Git is the only tool I've ever heard of  
> that has a problem with OS X using Unicode.

As far as I know, Subversion has basically exactly the same problem,  
and any time you consume/produce files on Mac OS X that are be  
consumed/produced on other platforms you will run into this kind of  
issue, with any software.

Tell Mac OS X to write a file with "ó" in the file name ("\xc3\xb3" in  
UTF-8), and it will "normalize" it prior to writing by converting it  
into a decomposed form (that is, ASCII "o" followed by "\xcc\x81", or  
"combining acute accent"). So they're both valid Unicode, both valid  
UTF-8, and they encode exactly the same characters but the byte stream  
is different.

If you only work on Mac OS X then this will never be a problem because  
all the files you create and therefore all the files you add to your  
Git repository will have their names in decomposed UTF-8. But when you  
start cloning repositories containing files added on other systems,  
systems which might use precomposed rather than decomposed UTF-8 then  
you'll run into exactly this kind of problem. The git.git repo has one  
such file itself (gitweb/test/Märchen, if I remember correctly, which  
Git reports as untracked).

Now, Mac OS X's behaviour is not entirely "insane" as some would  
claim; there is indeed a rationale behind it even if you don't agree  
with it, but it *does* produce some unfortunate teething problems for  
people wanting to use Mac OS X in a cross-platform environment.

Here are some Apple docs on the subject:

http://developer.apple.com/qa/qa2001/qa1173.html

http://developer.apple.com/qa/qa2001/qa1235.html

I personally wish that UTF-8 didn't allow different normalization  
forms; then this kind of problem wouldn't arise. But it has arisen and  
we have to live with it. Some workarounds have been proposed for Git,  
but I haven't seen any convincing proposals yet.

Cheers,
Wincent