Re: multibyte support (round 4) - tr

[Assaf Gordon]

Hello,

More progress on tr with multibyte support, available here:
https://files.housegordon.org/src/coreutils-multibyte-2017-12-23.patch.xz

translation (mostly) working:

   $ echo abcdefg | ./src/tr 'abcd' 'αβγδ'
   αβγδefg

   $ echo '1234 ABCD ΨΔΩΣ *$%()' \
              | ./src/tr -c '[:alpha:][:cntrl:]' 'Ψ'
   ΨΨΨΨΨABCDΨΨΔΩΣΨΨΨΨΨΨ

   $ echo 'αααββββ' | ./src/tr -s 'β' 'χ'
   αααχ

   $ echo 'aAbBcC ✀  χΧλΛσΣ' | ./src/tr '[:lower:]' '[:upper:]'
   AABBCC ✀  ΧΧΛΛΣΣ


The current implementation could be a starting point for
testing and discussing specific edge-cases (some tests are already 
included).

It is not tuned for efficiency (neither implementation nor run time 
performance).

There's a lot of code duplication due to keeping the entire current 
unibyte code-path intact.


comments welcomed.
 - assaf