Text::Diff::Table

Section: User Contributed Perl Documentation (3)
Updated: 2021-01-27
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NAME

  Text::Diff::Table - Text::Diff plugin to generate "table" format output

 

SYNOPSIS

  use Text::Diff;
  
  diff \@a, $b, { STYLE => "Table" };

 

DESCRIPTION

This is a plugin output formatter for Text::Diff that generates ``table'' style diffs:

  +--+----------------------------------+--+------------------------------+
  |  |../Test-Differences-0.2/MANIFEST  |  |../Test-Differences/MANIFEST  |
  |  |Thu Dec 13 15:38:49 2001          |  |Sat Dec 15 02:09:44 2001      |
  +--+----------------------------------+--+------------------------------+
  |  |                                  * 1|Changes                       *
  | 1|Differences.pm                    | 2|Differences.pm                |
  | 2|MANIFEST                          | 3|MANIFEST                      |
  |  |                                  * 4|MANIFEST.SKIP                 *
  | 3|Makefile.PL                       | 5|Makefile.PL                   |
  |  |                                  * 6|t/00escape.t                  *
  | 4|t/00flatten.t                     | 7|t/00flatten.t                 |
  | 5|t/01text_vs_data.t                | 8|t/01text_vs_data.t            |
  | 6|t/10test.t                        | 9|t/10test.t                    |
  +--+----------------------------------+--+------------------------------+

This format also goes to some pains to highlight ``invisible'' characters on differing elements by selectively escaping whitespace. Each element is split in to three segments (leading whitespace, body, trailing whitespace). If whitespace differs in a segement, that segment is whitespace escaped.

Here is an example of the selective whitespace.

  +--+--------------------------+--------------------------+
  |  |demo_ws_A.txt             |demo_ws_B.txt             |
  |  |Fri Dec 21 08:36:32 2001  |Fri Dec 21 08:36:50 2001  |
  +--+--------------------------+--------------------------+
  | 1|identical                 |identical                 |
  * 2|        spaced in         |        also spaced in    *
  * 3|embedded space            |embedded        tab       *
  | 4|identical                 |identical                 |
  * 5|        spaced in         |\ttabbed in               *
  * 6|trailing spaces\s\s\n     |trailing tabs\t\t\n       *
  | 7|identical                 |identical                 |
  * 8|lf line\n                 |crlf line\r\n             *
  * 9|embedded ws               |embedded\tws              *
  +--+--------------------------+--------------------------+

Here's why the lines do or do not have whitespace escaped:

lines 1, 4, 7 don't differ, no need.
lines 2, 3 differ in non-whitespace, no need.
lines 5, 6, 8, 9 all have subtle ws changes.

Whether or not line 3 should have that tab character escaped is a judgement call; so far I'm choosing not to.  

UNICODE

To output the raw unicode chracters consult the documentation of Text::Diff::Config. You can set the "DIFF_OUTPUT_UNICODE" environment variable to 1 to output it from the command line. For more information, consult this bug: <https://rt.cpan.org/Ticket/Display.html?id=54214> .  

LIMITATIONS

Table formatting requires buffering the entire diff in memory in order to calculate column widths. This format should only be used for smaller diffs.

Assumes tab stops every 8 characters, as $DIETY intended.

Assumes all character codes >= 127 need to be escaped as hex codes, ie that the user's terminal is ASCII, and not even ``high bit ASCII'', capable. This can be made an option when the need arises.

Assumes that control codes (character codes 0..31) that don't have slash-letter escapes (``\n'', ``\r'', etc) in Perl are best presented as hex escapes (``\x01'') instead of octal (``\001'') or control-code (``\cA'') escapes.  

AUTHOR

Barrie Slaymaker <barries@slaysys.com>  

LICENSE

Copyright 2001 Barrie Slaymaker, All Rights Reserved.

You may use this software under the terms of the GNU public license, any version, or the Artistic license.


 

Index

NAME
SYNOPSIS
DESCRIPTION
UNICODE
LIMITATIONS
AUTHOR
LICENSE