Ticket #448: PatchTask.php

<?php
/**
 *  Patches a file by applying a 'diff' file to it
 *
 *  Requires "patch" to be on the execution path.
 *
 *  Based on Apache Ant PatchTask:
 *
 *  Licensed to the Apache Software Foundation (ASF) under one or more
 *  contributor license agreements.  See the NOTICE file distributed with
 *  this work for additional information regarding copyright ownership.
 *  The ASF licenses this file to You under the Apache License, Version 2.0
 *  (the "License"); you may not use this file except in compliance with
 *  the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 *
 * @author Mikhail Krasilnikov <mk@3wstyle>
 * @version 0.01
 * @package phing.tasks.ext
 */
require_once 'phing/Task.php';

/**
 * Patches a file by applying a 'diff' file to it
 *
 * Requires "patch" to be on the execution path.
 *
 * @package phing.tasks.ext
 */
class PatchTask extends Task
{
    /**
     * Base command to be executed
     * @var string
     */
    const CMD = 'patch --batch ';

    /**
     * File to be patched
     * @var string
     */
    private $originalFile;

    /**
     * The directory to run the patch command in
     * @var string
     */
    private $directory;

    /**
     * Patch file
     *
     * @var string
     */
    private $patchFile;

    /**
     * Value for a "-p" option
     * @var int
     */
    private $strip = 0;

    /**
     * Command line arguments for patch binary
     * @var array
     */
    private $cmdArgs = array();

    /**
     * Halt on error return value from patch invocation.
     * @var bool
     */
    private $failOnError = false;

    /**
     * The file containing the diff output
     *
     * Required.
     * @param string $file  File containing the diff output
     * @return void
     * @throws BuildException if $file not exists
     */
    public function setPatchFile($file)
    {
        if (!is_file($file))
            throw new BuildException(sprintf('Patchfile %s doesn\'t exist', $file));

    $this->patchFile = $file;
    }

    /**
     * The file to patch
     *
     * Optional if it can be inferred from the diff file
     *
     * @param string $file  File to patch
     * @return void
     */
    public function setOriginalFile($file)
    {
        $this->originalFile = $file;
    }

    /**
     * The name of a file to send the output to, instead of patching
     * the file(s) in place
     *
     * Optional.
     *
     * @param string $file   File to send the output to
     * @return void
     */
    public function setDestFile($file)
    {
        if ($file !== null)
            $this->cmdArgs []= "-o $file";
    }

    /**
     * Flag to create backups
     *
     * Optional, default - false
     *
     * @param bool $backups  If true create backups
     * @return void
     */
    public function setBackups($backups)
    {
        if ($backups)
            $this->cmdArgs []= '-b';
    }

    /**
     * Flag to ignore whitespace differences;
     *
     * Default - false
     *
     * @param bool $ignore  If true ignore whitespace differences
     * @return void
     */
    public function setIgnoreWhiteSpace($ignore)
    {
        if ($ignore)
            $this->cmdArgs []= '-l';
    }

    /**
     * Strip the smallest prefix containing <i>num</i> leading slashes
     * from filenames.
     *
     * patch's <i>-p</i> option.
     *
     * @param int $num number of lines to strip
     * @return void
     * @throws BuildException if num is < 0, or other errors
     */
    public function setStrip($num)
    {
        if ($num < 0)
            throw new BuildException('strip has to be >= 0');

        $this->strip = $num;
    }

    /**
     * Work silently unless an error occurs
     *
     * Optional, default - false
     * @param bool $q  If true suppress set the -s option on the patch command
     * @return void
     */
    public function setQuiet($q)
    {
        if ($q)
            $this->cmdArgs []= '-s';
    }

    /**
     * Assume patch was created with old and new files swapped
     *
     * Optional, default - false
     *
     * @param bool $r  If true set the -R option on the patch command
     * @return void
     */
    public function setReverse($r)
    {
        if ($r)
            $this->cmdArgs []= '-R';
    }

    /**
     * The directory to run the patch command in
     *
     * Defaults to the project's base directory.
     *
     * @param string $directory  Directory to run the patch command in
     * @return void
     */
    public function setDir($directory)
    {
        $this->directory = $directory;
    }

    /**
     * If true, stop the build process if the patch command
     * exits with an error status.
     *
     * The default is "false"
     *
     * @param bool $value  "true" if it should halt, otherwise "false"
     * @return void
     */
    public function setFailOnError($value)
    {
        $this->failOnError = $value;
    }

    /**
     * Main task method
     *
     * @return void
     * @throws BuildException when it all goes a bit pear shaped
     */
    public function main()
    {
        if ($this->patchFile == null)
            throw new BuildException('patchfile argument is required');

        // Define patch file
        $this->cmdArgs []= '-i ' . $this->patchFile;
        // Define strip factor
        $this->cmdArgs []= '-p' . $this->strip;
        // Define original file if specified
        if ($this->originalFile != null)
            $this->cmdArgs []= $this->originalFile;

        $cmd = self::CMD . implode(' ', $this->cmdArgs);

/*        if (directory != null) {
            if (directory.exists() && directory.isDirectory()) {
                exe.setWorkingDirectory(directory);
            } else if (!directory.isDirectory()) {
                throw new BuildException(directory + " is not a directory.",
                                         getLocation());
            } else {
                throw new BuildException("directory " + directory
                                         + " doesn\'t exist", getLocation());
            }
        } else {
            exe.setWorkingDirectory(getProject().getBaseDir());
        }
*/
        $this->log('Applying patch: ' . $this->patchFile);

        exec($cmd, $output, $exitCode);

        foreach ($output as $line)
            $this->log($line, Project::MSG_VERBOSE);

        if ($exitCode != 0)
            throw new BuildException( "Task exited with code $exitCode" );

    }
}