SYNOPSIS

        use Test::More;
        use Test::BOM
    
        string_has_bom("\x00\x00\xfe\xff");
        string_hasnt_bom("blargh");
    
        file_has_bom('t/data/foo');
        file_hasnt_bom('t/data/bar');

DESCRIPTION

    This module helps you with testing for byte-order-marks in strings and
    files.

    If you came across this module while looking for other ways to deal
    with byte-order-marks you might find what you need in the "SEE ALSO"
    section below.

    If you don't know anything about automated testing in Perl then you
    should read about Test::More before preceding. This module uses the
    Test::Builder framework.

    Byte-order-marks are by definition to be found at the beginning of any
    content, so the functions this module provides take a look at the start
    of either a string or a file. It does this by using functions from
    String::BOM and basically just wraps them for use with Test::Builder.

    By default the following functions are imported into your namespace:
    string_has_bom, string_hasnt_bom, file_has_bom, file_hasnt_bom.

FUNCTIONS

 string_has_bom ($string)

    Passes if the string has a BOM, fails if not.

 string_hasnt_bom ($string)

    Passes if string doesn't have a BOM, fails if it has.

 file_has_bom ($filename)

    Passes if the file has a BOM, fails if it doesn't.

 file_hasnt_bom ($filename)

    Passes if the file doesn't have a BOM, fails if it has.

SEE ALSO

    There are some distributions that help you dealing with BOMs in
    different ways:

    String::BOM is used by this module to check for BOM.

    File::BOM::Utils contains functions to check for, add and remove BOM
    from files.

    File::BOM can be used to actually read from files that have BOMs as
    seamlessly as possible.

    PPI::Token::BOM represents a BOM when using PPI to parse perl.

    The distribution Dist::Zilla::Plugin::Web contains the module
    Dist::Zilla::Plugin::Web::StripBOM that strips BOM from files.

    Additional information about BOM and it's usage:

    http://www.unicode.org/faq/utf_bom.html#BOM is the FAQ for the BOM from
    the Unicode Consortium.

    https://docs.microsoft.com/de-de/windows/desktop/Intl/using-byte-order-marks
    explains how Microsoft wants the BOM to be used. Since this document
    dates from 2018 (as of this writing) it's very likely to get in contact
    with files containing BOM.