NAME
    File::Patch::Undoable - Patch a file, with undo support

VERSION
    This document describes version 0.09 of File::Patch::Undoable (from Perl
    distribution File-Patch-Undoable), released on 2017-07-10.

KNOWN ISSUES
FUNCTIONS
  patch
    Usage:

     patch(%args) -> [status, msg, result, meta]

    Patch a file, with undo support.

    On do, will patch file with the supplied patch. On undo, will apply the
    reverse of the patch.

    Note: Symlink is currently not permitted (except for the patch file).
    Patching is currently done with the patch program.

    Unfixable state: file does not exist or not a regular file (directory
    and symlink included), patch file does not exist or not a regular file
    (but symlink allowed).

    Fixed state: file exists, patch file exists, and patch has been applied.

    Fixable state: file exists, patch file exists, and patch has not been
    applied.

    This function is not exported.

    This function is idempotent (repeated invocations with same arguments
    has the same effect as single invocation). This function supports
    transactions.

    Arguments ('*' denotes required arguments):

    *   file* => *str*

        Path to file to be patched.

    *   patch* => *str*

        Path to patch file.

        Patch can be in unified or context format, it will be autodetected.

    *   reverse => *bool* (default: 0)

        Whether to apply reverse of patch.

    Special arguments:

    *   -tx_action => *str*

        For more information on transaction, see Rinci::Transaction.

    *   -tx_action_id => *str*

        For more information on transaction, see Rinci::Transaction.

    *   -tx_recovery => *str*

        For more information on transaction, see Rinci::Transaction.

    *   -tx_rollback => *str*

        For more information on transaction, see Rinci::Transaction.

    *   -tx_v => *str*

        For more information on transaction, see Rinci::Transaction.

    Returns an enveloped result (an array).

    First element (status) is an integer containing HTTP status code (200
    means OK, 4xx caller error, 5xx function error). Second element (msg) is
    a string containing error message, or 'OK' if status is 200. Third
    element (result) is optional, the actual result. Fourth element (meta)
    is called result metadata and is optional, a hash that contains extra
    information.

    Return value: (any)

FAQ
  Why use the patch program? Why not use a Perl module like Text::Patch?
    The patch program has many nice features that Text::Patch lacks, e.g.
    applying reverse patch (needed to check fixed state and to undo),
    autodetection of patch type, ignoring whitespace and fuzz factor, etc.

HOMEPAGE
    Please visit the project's homepage at
    <https://metacpan.org/release/File-Patch-Undoable>.

SOURCE
    Source repository is at
    <https://github.com/perlancar/perl-File-Patch-Undoable>.

BUGS
    Please report any bugs or feature requests on the bugtracker website
    <https://rt.cpan.org/Public/Dist/Display.html?Name=File-Patch-Undoable>

    When submitting a bug or request, please include a test-file or a patch
    to an existing test-file that illustrates the bug or desired feature.

SEE ALSO
    Rinci::Transaction

    Text::Patch, PatchReader, Text::Patch::Rred

AUTHOR
    perlancar <perlancar@cpan.org>

COPYRIGHT AND LICENSE
    This software is copyright (c) 2017, 2016, 2015, 2014, 2012 by
    perlancar@cpan.org.

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