Hi there,

I'm using Text::CharWidth (recommended from http://www.perlmonks.org/?node_id=713326) to determine the display width of UTF-8 strings in a module I just released (https://metacpan.org/release/Text-UnicodeBox). I'm running into an issue with *BSD boxes and I believe I've narrowed it down to the environment. Take this simple test script:

use Test::More;
use Text::CharWidth qw(:all);

my $string = " \x{8c61}\x{5f62}\x{6587}\x{5b57}\x{8c61}\x{5f62}\x{6587
+}\x{5b57} ";
ok utf8::valid($string), "is valid utf8";
is length($string), 10, "There are 10 bytes";
is mbswidth($string), 18, "CharWidth of kanji";

done_testing;
[download]

This works just fine so long as your LC_* environment variables are configured. The issue, though, is that apparently all the CPAN testers out there don't have the locale set when they run this, which breaks CharWidth (Text::CharWidth uses the system function wcwidth, which uses your locale settings - http://www.manpagez.com/man/3/wcwidth/). Here's an example of it breaking:

$ LC_ALL= prove -l -v t/simple_unicode_test.t 
t/simple_unicode_test.t .. 
ok 1 - is valid utf8
ok 2 - There are 10 bytes
not ok 3 - CharWidth of kanji
1..3

#   Failed test 'CharWidth of kanji'
#   at t/simple_unicode_test.t line 9.
#          got: '-22'
#     expected: '18'
# Looks like you failed 1 test of 3.
Dubious, test returned 1 (wstat 256, 0x100)
Failed 1/3 subtests 

Test Summary Report
-------------------
t/simple_unicode_test.t (Wstat: 256 Tests: 3 Failed: 1)
  Failed test:  3
  Non-zero exit status: 1
Files=1, Tests=3,  0 wallclock secs ( 0.02 usr  0.03 sys +  0.03 cusr 
+ 0.01 csys =  0.09 CPU)
Result: FAIL
[download]

This is simplified, of course. Here's one of the actual failing test reports

And another example (from http://www.perlmonks.org/?node_id=713326) of how LC_ALL= can mess up CharWidth:

$ perl -C63 -MDevel::Peek -Mutf8 -mText::CharWidth=mbswidth -le '$_="(
+\x{5fcd} Guimarães)"; Dump($_); print mbswidth($_);'

SV = PV(0x8101064) at 0x8100118
  REFCNT = 1
  FLAGS = (POK,pPOK,UTF8)
  PV = 0x814b740 "(\345\277\215 Guimar\303\243es)"\0 [UTF8 "(\x{5fcd} 
+Guimar\x{e3}es)"]
  CUR = 16
  LEN = 20
14

$ LC_ALL= perl -C63 -MDevel::Peek -Mutf8 -mText::CharWidth=mbswidth -l
+e '$_="(\x{5fcd} Guiarães)"; Dump($_); print mbswidth($_);'

SV = PV(0x8101064) at 0x8100118
  REFCNT = 1
  FLAGS = (POK,pPOK,UTF8)
  PV = 0x814b740 "(\345\277\215 Guimar\303\243es)"\0 [UTF8 "(\x{5fcd} 
+Guimar\x{e3}es)"]
  CUR = 16
  LEN = 20
6
[download]

So, how do I get my code to pass CPAN tests on *BSD boxes without LC_* set? I've tried adding it to the tests but to no avail.