NAME
    Test::Mojibake - check your source for encoding misbehavior.

VERSION
    version 0.5

SYNOPSIS
        # Test::Mojibake lets you check for inconsistencies in source/documentation encoding, and report its results in standard Test::Simple fashion.

        use Test::Mojibake;
        file_encoding_ok($file, 'Valid encoding');
        done_testing($num_tests);

DESCRIPTION
    Many modern text editors automatically save files using UTF-8
    codification, however, perl interpreter does not expects it *by
    default*. Whereas this does not represent a big deal on (most)
    backend-oriented programs, Web framework (Catalyst
    <http://www.catalystframework.org/>, Mojolicious <http://mojolicio.us/>)
    based applications will suffer of so-called Mojibake
    <http://en.wikipedia.org/wiki/Mojibake> (lit. "unintelligible sequence
    of characters").

    Even worse: if an editor saves BOM (Byte Order Mark, "U+FEFF" character
    in Unicode) at the start of the script with executable bit set (on Unix
    systems), it won't execute at all, due to shebang corruption.

    Avoiding codification problems is quite simple:

    *   Always "use utf8"/"use common::sense" when saving source as UTF-8;

    *   Always specify "=encoding utf8" when saving POD as UTF-8;

    *   Do neither of above when saving as ISO-8859-1;

    *   Never save BOM (not that it's wrong; just avoid it as you'll barely
        notice it's presence when in trouble).

    However, if you find yourself upgrading old code to use UTF-8 or trying
    to standardize a big project with many developers each one using a
    different platform/editor, reviewing all files manually can be quite
    painful. Specially in cases when some files have multiple encodings
    (note: it all started when I realized that *Gedit* & derivatives are
    unable to open files with character conversion tables).

    Enter the Test::Mojibake ";)"

FUNCTIONS
  file_encoding_ok( FILENAME[, TESTNAME ] )
    Validates the codification of "FILENAME".

    When it fails, "file_encoding_ok()" will report the probable cause.

    The optional second argument "TESTNAME" is the name of the test. If it
    is omitted, "file_encoding_ok()" chooses a default test name "Mojibake
    test for FILENAME".

  all_files_encoding_ok( [@entries] )
    Validates codification of all the files under @entries. It runs
    "all_files()" on directories and assumes everything else to be a file to
    be tested. It calls the "plan()" function for you (one test for each
    file), so you can't have already called "plan".

    If @entries is empty or not passed, the function finds all
    source/documentation files in files in the blib directory if it exists,
    or the lib directory if not. A source/documentation file is one that
    ends with .pod, .pl and .pm, or any file where the first line looks like
    a shebang line.

  all_files( [@dirs] )
    Returns a list of all the Perl files in *@dirs* and in directories
    below. If no directories are passed, it defaults to blib if blib exists,
    or else lib if not. Skips any files in CVS, .svn, .git and similar
    directories. See %Test::Mojibake::ignore_dirs for a list of them.

    A Perl file is:

    *   Any file that ends in .PL, .pl, .pm, .pod, or .t;

    *   Any file that has a first line with a shebang and "perl" on it;

    *   Any file that ends in .bat and has a first line with "--*-Perl-*--"
        on it.

    The order of the files returned is machine-dependent. If you want them
    sorted, you'll have to sort them yourself.

  _detect_utf8( \$string )
    Detects presence of UTF-8 encoded characters in a referenced octet
    stream.

    Return codes:

    *   0 - 8-bit characters detected, does not validate as UTF-8;

    *   1 - only 7-bit characters;

    *   2 - 8-bit characters detected, validates as UTF-8.

    Unicode::CheckUTF8 is highly recommended, however, it is optional and
    this function will fallback to the Pure Perl implementation of the
    following PHP code:
    <http://www.php.net/manual/en/function.utf8-encode.php#85293>

SAMPLE TEST SCRIPT
    Module authors can include the following in a t/mojibake.t file and have
    Test::Mojibake automatically find and check all source files in a module
    distribution:

        #!perl -T
        use strict;

        BEGIN {
            unless ($ENV{RELEASE_TESTING}) {
                require Test::More;
                Test::More::plan(skip_all => 'these tests are for release candidate testing');
            }
        }

        use Test::More;

        eval 'use Test::Mojibake';
        plan skip_all => 'Test::Mojibake required for source encoding testing' if $@;

        all_files_encoding_ok();

OPERATION
    Test::Mojibake validates codification of both source (Perl code) and
    documentation (POD). Both are assumed to be encoded in ISO-8859-1 (aka
    latin1). Perl switches to UTF-8 through the statement:

     use utf8;

    or:

     use common::sense;

    Similarly, POD encoding can be changed via:

     =encoding utf8

    Correspondingly, "no utf8"/"=encoding latin1" put Perl back into
    ISO-8859-1 mode.

    Actually, Test::Mojibake only cares about UTF-8, as it is roughly safe
    to be detected. So, when UTF-8 characters are detected without preceding
    declaration, an error is reported. On the other way, non-UTF-8
    characters in UTF-8 mode are wrong, either.

    If present, Unicode::CheckUTF8 module (XS wrapper) will be used to
    validate UTF-8 strings, note that it is 30 times faster and a lot more
    Unicode Consortium compliant than the built-in Pure Perl implementation!

    UTF-8 BOM (Byte Order Mark) is also detected as an error. While Perl is
    OK handling BOM, your OS probably isn't. Check out:

     ./bom.pl: line 1: $'\357\273\277#!/usr/bin/perl': command not found

  Caveats
    Whole-line source comments, like:

     # this is a whole-line comment...
     print "### hello world ###\n"; # ...and this os not

    are not checked at all. This is mainly because many scripts/modules do
    contain authors' names in headers, before the proper encoding
    specification. So, if you happen to have some acutes/umlauts in your
    name and your editor sign your code in the similar way, you probably
    won't be happy with Test::Mojibake flooding you with (false) error
    messages.

    If you are wondering why only whole-line comments are stripped, check
    the second line of the above example.

SEE ALSO
    *   common::sense

    *   Dist::Zilla::Plugin::MojibakeTests

    *   Test::Perl::Critic

    *   Test::Pod

    *   Test::Pod::Coverage

    *   Test::Kwalitee

ACKNOWLEDGEMENTS
    This module is based on Test::Pod.

    Thanks to Andy Lester, David Wheeler, Paul Miller and Peter Edwards for
    contributions and to "brian d foy" for the original code.

AUTHOR
    Stanislaw Pusep <stas@sysd.org>

COPYRIGHT AND LICENSE
    This software is copyright (c) 2012 by Stanislaw Pusep.

    This is free software; you can redistribute it and/or modify it under
    the same terms as the Perl 5 programming language system itself.