/** * A class to render Diffs in different formats. * * This class renders the diff in classic diff format. It is intended that * this class be customized via inheritance, to obtain fancier outputs. * * Copyright 2004-2010 The Horde Project (http://www.horde.org/) * * See the enclosed file COPYING for license information (LGPL). If you did * not receive this file, see http://opensource.org/licenses/lgpl-license.php. * * @package Text_Diff */ class Text_Diff_Renderer { /** * 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. */ var $_leading_context_lines = 0; /** * 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. */ var $_trailing_context_lines = 0; /** * Constructor. */ function __construct( $params = array() ) { foreach ($params as $param => $value) { $v = '_' . $param; if (isset($this->$v)) { $this->$v = $value; } } } /** * PHP4 constructor. */ public function Text_Diff_Renderer( $params = array() ) { self::__construct( $params ); } /** * Get any renderer parameters. * * @return array All parameters of this renderer object. */ function getParams() { $params = array(); foreach (get_object_vars($this) as $k => $v) { if ($k[0] == '_') { $params[substr($k, 1)] = $v; } } return $params; } /** * Renders a diff. * * @param Text_Diff $diff A Text_Diff object. * * @return string The formatted output. */ function render($diff) { $xi = $yi = 1; $block = false; $context = array(); $nlead = $this->_leading_context_lines; $ntrail = $this->_trailing_context_lines; $output = $this->_startDiff(); $diffs = $diff->getDiff(); foreach ($diffs as $i => $edit) { /* If these are unchanged (copied) lines, and we want to keep * leading or trailing context lines, extract them from the copy * block. */ if (is_a($edit, 'Text_Diff_Op_copy')) { /* Do we have any diff blocks yet? */ if (is_array($block)) { /* How many lines to keep as context from the copy * block. */ $keep = $i == count($diffs) - 1 ? $ntrail : $nlead + $ntrail; if (count($edit->orig) <= $keep) { /* We have less lines in the block than we want for * context => keep the whole block. */ $block[] = $edit; } else { if ($ntrail) { /* Create a new block with as many lines as we need * for the trailing context. */ $context = array_slice($edit->orig, 0, $ntrail); $block[] = new Text_Diff_Op_copy($context); } /* @todo */ $output .= $this->_block($x0, $ntrail + $xi - $x0, $y0, $ntrail + $yi - $y0, $block); $block = false; } } /* Keep the copy block as the context for the next block. */ $context = $edit->orig; } else { /* Don't we have any diff blocks yet? */ if (!is_array($block)) { /* Extract context lines from the preceding copy block. */ $context = array_slice($context, count($context) - $nlead); $x0 = $xi - count($context); $y0 = $yi - count($context); $block = array(); if ($context) { $block[] = new Text_Diff_Op_copy($context); } } $block[] = $edit; } if ($edit->orig) { $xi += count($edit->orig); } if ($edit->final) { $yi += count($edit->final); } } if (is_array($block)) { $output .= $this->_block($x0, $xi - $x0, $y0, $yi - $y0, $block); } return $output . $this->_endDiff(); } function _block($xbeg, $xlen, $ybeg, $ylen, &$edits) { $output = $this->_startBlock($this->_blockHeader($xbeg, $xlen, $ybeg, $ylen)); foreach ($edits as $edit) { switch (strtolower(get_class($edit))) { case 'text_diff_op_copy': $output .= $this->_context($edit->orig); break; case 'text_diff_op_add': $output .= $this->_added($edit->final); break; case 'text_diff_op_delete': $output .= $this->_deleted($edit->orig); break; case 'text_diff_op_change': $output .= $this->_changed($edit->orig, $edit->final); break; } } return $output . $this->_endBlock(); } function _startDiff() { return ''; } function _endDiff() { return ''; } function _blockHeader($xbeg, $xlen, $ybeg, $ylen) { if ($xlen > 1) { $xbeg .= ',' . ($xbeg + $xlen - 1); } if ($ylen > 1) { $ybeg .= ',' . ($ybeg + $ylen - 1); } // this matches the GNU Diff behaviour if ($xlen && !$ylen) { $ybeg--; } elseif (!$xlen) { $xbeg--; } return $xbeg . ($xlen ? ($ylen ? 'c' : 'd') : 'a') . $ybeg; } function _startBlock($header) { return $header . "\n"; } function _endBlock() { return ''; } function _lines($lines, $prefix = ' ') { return $prefix . implode("\n$prefix", $lines) . "\n"; } function _context($lines) { return $this->_lines($lines, ' '); } function _added($lines) { return $this->_lines($lines, '> '); } function _deleted($lines) { return $this->_lines($lines, '< '); } function _changed($orig, $final) { return $this->_deleted($orig) . "---\n" . $this->_added($final); } }