--- /dev/null
+<?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;
+
+ /** @var string The output buffer; holds the output while it is built. */
+ private $result = '';
+
+ /**
+ * Format a diff.
+ *
+ * @param Diff $diff
+ *
+ * @return string The formatted output.
+ */
+ public function format( $diff ) {
+ $xi = $yi = 1;
+ $block = false;
+ $context = [];
+
+ $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 = [];
+ 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();
+
+ 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 ) {
+ $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();
+ }
+
+ protected function startDiff() {
+ $this->result = '';
+ }
+
+ /**
+ * Writes a string to the output buffer.
+ *
+ * @param string $text
+ */
+ protected function writeOutput( $text ) {
+ $this->result .= $text;
+ }
+
+ /**
+ * @return string
+ */
+ protected function endDiff() {
+ $val = $this->result;
+ $this->result = '';
+
+ 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 ) {
+ $this->writeOutput( $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 ) {
+ $this->writeOutput( "$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 );
+ $this->writeOutput( "---\n" );
+ $this->added( $closing );
+ }
+
+}
scripts.mit.edu / autoinstallsdev / mediawiki.git / blobdiff