diff options
Diffstat (limited to 'includes/diff/DiffFormatter.php')
| -rw-r--r-- | includes/diff/DiffFormatter.php | 247 |
1 files changed, 247 insertions, 0 deletions
diff --git a/includes/diff/DiffFormatter.php b/includes/diff/DiffFormatter.php new file mode 100644 index 00000000..40df0d75 --- /dev/null +++ b/includes/diff/DiffFormatter.php @@ -0,0 +1,247 @@ +<?php +/** + * Base for diff rendering classes. Portions taken from phpwiki-1.3.3. + * + * Copyright © 2000, 2001 Geoffrey T. Dairiki <dairiki@dairiki.org> + * You may copy this code freely under the conditions of the GPL. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. + * http://www.gnu.org/copyleft/gpl.html + * + * @file + * @ingroup DifferenceEngine + */ + +/** + * Base class for diff formatters + * + * This class formats the diff in classic diff format. + * It is intended that this class be customized via inheritance, + * to obtain fancier outputs. + * @todo document + * @ingroup DifferenceEngine + */ +abstract class DiffFormatter { + + /** @var int Number of leading context "lines" to preserve. + * + * This should be left at zero for this class, but subclasses + * may want to set this to other values. + */ + protected $leadingContextLines = 0; + + /** @var int Number of trailing context "lines" to preserve. + * + * This should be left at zero for this class, but subclasses + * may want to set this to other values. + */ + protected $trailingContextLines = 0; + + /** + * Format a diff. + * + * @param Diff $diff + * + * @return string The formatted output. + */ + public function format( $diff ) { + wfProfileIn( __METHOD__ ); + + $xi = $yi = 1; + $block = false; + $context = array(); + + $nlead = $this->leadingContextLines; + $ntrail = $this->trailingContextLines; + + $this->startDiff(); + + // Initialize $x0 and $y0 to prevent IDEs from getting confused. + $x0 = $y0 = 0; + foreach ( $diff->edits as $edit ) { + if ( $edit->type == 'copy' ) { + if ( is_array( $block ) ) { + if ( count( $edit->orig ) <= $nlead + $ntrail ) { + $block[] = $edit; + } else { + if ( $ntrail ) { + $context = array_slice( $edit->orig, 0, $ntrail ); + $block[] = new DiffOpCopy( $context ); + } + $this->block( $x0, $ntrail + $xi - $x0, + $y0, $ntrail + $yi - $y0, + $block ); + $block = false; + } + } + $context = $edit->orig; + } else { + if ( !is_array( $block ) ) { + $context = array_slice( $context, count( $context ) - $nlead ); + $x0 = $xi - count( $context ); + $y0 = $yi - count( $context ); + $block = array(); + if ( $context ) { + $block[] = new DiffOpCopy( $context ); + } + } + $block[] = $edit; + } + + if ( $edit->orig ) { + $xi += count( $edit->orig ); + } + if ( $edit->closing ) { + $yi += count( $edit->closing ); + } + } + + if ( is_array( $block ) ) { + $this->block( $x0, $xi - $x0, + $y0, $yi - $y0, + $block ); + } + + $end = $this->endDiff(); + wfProfileOut( __METHOD__ ); + + return $end; + } + + /** + * @param int $xbeg + * @param int $xlen + * @param int $ybeg + * @param int $ylen + * @param array $edits + * + * @throws MWException If the edit type is not known. + */ + protected function block( $xbeg, $xlen, $ybeg, $ylen, &$edits ) { + wfProfileIn( __METHOD__ ); + $this->startBlock( $this->blockHeader( $xbeg, $xlen, $ybeg, $ylen ) ); + foreach ( $edits as $edit ) { + if ( $edit->type == 'copy' ) { + $this->context( $edit->orig ); + } elseif ( $edit->type == 'add' ) { + $this->added( $edit->closing ); + } elseif ( $edit->type == 'delete' ) { + $this->deleted( $edit->orig ); + } elseif ( $edit->type == 'change' ) { + $this->changed( $edit->orig, $edit->closing ); + } else { + throw new MWException( "Unknown edit type: {$edit->type}" ); + } + } + $this->endBlock(); + wfProfileOut( __METHOD__ ); + } + + protected function startDiff() { + ob_start(); + } + + /** + * @return string + */ + protected function endDiff() { + $val = ob_get_contents(); + ob_end_clean(); + + return $val; + } + + /** + * @param int $xbeg + * @param int $xlen + * @param int $ybeg + * @param int $ylen + * + * @return string + */ + protected function blockHeader( $xbeg, $xlen, $ybeg, $ylen ) { + if ( $xlen > 1 ) { + $xbeg .= ',' . ( $xbeg + $xlen - 1 ); + } + if ( $ylen > 1 ) { + $ybeg .= ',' . ( $ybeg + $ylen - 1 ); + } + + return $xbeg . ( $xlen ? ( $ylen ? 'c' : 'd' ) : 'a' ) . $ybeg; + } + + /** + * Called at the start of a block of connected edits. + * This default implementation writes the header and a newline to the output buffer. + * + * @param string $header + */ + protected function startBlock( $header ) { + echo $header . "\n"; + } + + /** + * Called at the end of a block of connected edits. + * This default implementation does nothing. + */ + protected function endBlock() { + } + + /** + * Writes all (optionally prefixed) lines to the output buffer, separated by newlines. + * + * @param string[] $lines + * @param string $prefix + */ + protected function lines( $lines, $prefix = ' ' ) { + foreach ( $lines as $line ) { + echo "$prefix $line\n"; + } + } + + /** + * @param string[] $lines + */ + protected function context( $lines ) { + $this->lines( $lines ); + } + + /** + * @param string[] $lines + */ + protected function added( $lines ) { + $this->lines( $lines, '>' ); + } + + /** + * @param string[] $lines + */ + protected function deleted( $lines ) { + $this->lines( $lines, '<' ); + } + + /** + * Writes the two sets of lines to the output buffer, separated by "---" and a newline. + * + * @param string[] $orig + * @param string[] $closing + */ + protected function changed( $orig, $closing ) { + $this->deleted( $orig ); + echo "---\n"; + $this->added( $closing ); + } + +} |