Re: [coreutils] tr: case mapping anomaly

[Pádraig Brady]

On 29/09/10 12:59, Eric Blake wrote:

Thanks for the review.

I agree with your tweaks, though since I've already pushed,
I don't think it's worth amending.

>> +
>> +    # Ensure we extend string2 appropriately
>> +    tr '[:upper:]- ' '[:lower:]_' < /dev/null || _fail=1
> 
> Seems non-portable to have a - in the middle, even though here the left
> side is a character class instead of a byte.  I think you'd better pick
> a different character than -, or move the - to the end.

Well that was part by design, as it's our tr that we're testing, and
this will flag if we inadvertently change range processing within tr.

>> +    # Ensure the size of the case classes are accounted
>> +    # for as a unit.
>> +    echo 'ABCDEFGHIJKLMNOPQRSTUVWXYZ' |
>> +    tr '[:upper:]A-B' '[:lower:]0' >out ||  _fail=1
>> +    echo '00cdefghijklmnopqrstuvwxyz' > exp
> 
> Huh?  A and B are both in [:upper:]; when a character is listed more
> than once in string1, it is only transliterated according to the first
> listing.  I think this should be 'abc...' not '00c...' for the expected
> results.

Does POSIX specify that?
That's not what we do, nor what I would expect.

$ echo 'A' | LANG=C tr 'AA' '01'
1

cheers,
Pádraig.