NAME
    "Test::HexString" - test binary strings with hex dump diagnostics

SYNOPSIS
     use Test::More tests => 1;
     use Test::HexString;

     my $data = generate_some_output;

     is_hexstr( $data, "\x01\x02\x03\x04", 'Generated output' );

DESCRIPTION
    This testing module provides a single function, "is_hexstr()", which
    asserts that the given string matches what was expected. When the
    strings match (i.e. compare equal using the "eq" operator), the
    behaviour is identical to the usual "is()" function provided by
    "Test::More".

    When the strings are different, a hex dump is produced as diagnostic,
    rather than the string values being printed raw. This may be beneficial
    if the string contains largely binary data, such as may be produced by
    binary file or network protocol modules.

    To print the hex dump when it fails, each string is broken into 16 byte
    chunks. The first pair of chunks that fail to match are then printed, in
    both hexadecimal and character form, in a message in the following
    format:

     #   Failed test at -e line 1.
     #   at bytes 0-0xf (0-15)
     #   got: | 61 20 6c 6f 6e 67 20 73 74 72 69 6e 67 20 68 65 |a long string he|
     #   exp: | 61 20 6c 6f 6e 67 20 53 74 72 69 6e 67 20 68 65 |a long String he|
     # Looks like you failed 1 test of 1.

    Only bytes in the range "0x20-0x7e" are printed as literal characters.
    Any other byte is rendered as ".":

     #   Failed test at -e line 1.
     #   at bytes 0-0xf (0-15)
     #   got: | 00 01 02 03 04 05 06 07 08 09 0a 0b 0c 0d 0e 0f |................|
     #   exp: | 01 02 03 04 05 06 07 08 09 0a 0b 0c 0d 0e 0f 10 |................|
     # Looks like you failed 1 test of 1.

    Only the first differing line is printed; because otherwise it may
    result in a long output because of misaligned bytes.

    If STDOUT is a terminal, then different bytes are printed in bold for
    visibility.

FUNCTIONS
  is_hexstr( $got, $expect, $name )
    Test that the string $got is what was expected by $expect. If the
    strings are not equal, a hex dump is printed showing the region where
    they first start to differ.

AUTHOR
    Paul Evans <leonerd@leonerd.org.uk>

