website_jukni/dokuwiki/inc/DifferenceEngine.php
2017-12-29 15:51:59 +01:00

1521 lines
46 KiB
PHP

<?php
/**
* A PHP diff engine for phpwiki. (Taken from phpwiki-1.3.3)
*
* Additions by Axel Boldt for MediaWiki
*
* @copyright (C) 2000, 2001 Geoffrey T. Dairiki <dairiki@dairiki.org>
* @license You may copy this code freely under the conditions of the GPL.
*/
define('USE_ASSERTS', function_exists('assert'));
class _DiffOp {
var $type;
var $orig;
var $closing;
/**
* @return _DiffOp
*/
function reverse() {
trigger_error("pure virtual", E_USER_ERROR);
}
function norig() {
return $this->orig ? count($this->orig) : 0;
}
function nclosing() {
return $this->closing ? count($this->closing) : 0;
}
}
class _DiffOp_Copy extends _DiffOp {
var $type = 'copy';
function __construct($orig, $closing = false) {
if (!is_array($closing))
$closing = $orig;
$this->orig = $orig;
$this->closing = $closing;
}
function reverse() {
return new _DiffOp_Copy($this->closing, $this->orig);
}
}
class _DiffOp_Delete extends _DiffOp {
var $type = 'delete';
function __construct($lines) {
$this->orig = $lines;
$this->closing = false;
}
function reverse() {
return new _DiffOp_Add($this->orig);
}
}
class _DiffOp_Add extends _DiffOp {
var $type = 'add';
function __construct($lines) {
$this->closing = $lines;
$this->orig = false;
}
function reverse() {
return new _DiffOp_Delete($this->closing);
}
}
class _DiffOp_Change extends _DiffOp {
var $type = 'change';
function __construct($orig, $closing) {
$this->orig = $orig;
$this->closing = $closing;
}
function reverse() {
return new _DiffOp_Change($this->closing, $this->orig);
}
}
/**
* Class used internally by Diff to actually compute the diffs.
*
* The algorithm used here is mostly lifted from the perl module
* Algorithm::Diff (version 1.06) by Ned Konz, which is available at:
* http://www.perl.com/CPAN/authors/id/N/NE/NEDKONZ/Algorithm-Diff-1.06.zip
*
* More ideas are taken from:
* http://www.ics.uci.edu/~eppstein/161/960229.html
*
* Some ideas are (and a bit of code) are from from analyze.c, from GNU
* diffutils-2.7, which can be found at:
* ftp://gnudist.gnu.org/pub/gnu/diffutils/diffutils-2.7.tar.gz
*
* closingly, some ideas (subdivision by NCHUNKS > 2, and some optimizations)
* are my own.
*
* @author Geoffrey T. Dairiki
* @access private
*/
class _DiffEngine {
var $xchanged = array();
var $ychanged = array();
var $xv = array();
var $yv = array();
var $xind = array();
var $yind = array();
var $seq;
var $in_seq;
var $lcs;
/**
* @param array $from_lines
* @param array $to_lines
* @return _DiffOp[]
*/
function diff($from_lines, $to_lines) {
$n_from = count($from_lines);
$n_to = count($to_lines);
$this->xchanged = $this->ychanged = array();
$this->xv = $this->yv = array();
$this->xind = $this->yind = array();
unset($this->seq);
unset($this->in_seq);
unset($this->lcs);
// Skip leading common lines.
for ($skip = 0; $skip < $n_from && $skip < $n_to; $skip++) {
if ($from_lines[$skip] != $to_lines[$skip])
break;
$this->xchanged[$skip] = $this->ychanged[$skip] = false;
}
// Skip trailing common lines.
$xi = $n_from;
$yi = $n_to;
for ($endskip = 0; --$xi > $skip && --$yi > $skip; $endskip++) {
if ($from_lines[$xi] != $to_lines[$yi])
break;
$this->xchanged[$xi] = $this->ychanged[$yi] = false;
}
// Ignore lines which do not exist in both files.
for ($xi = $skip; $xi < $n_from - $endskip; $xi++)
$xhash[$from_lines[$xi]] = 1;
for ($yi = $skip; $yi < $n_to - $endskip; $yi++) {
$line = $to_lines[$yi];
if (($this->ychanged[$yi] = empty($xhash[$line])))
continue;
$yhash[$line] = 1;
$this->yv[] = $line;
$this->yind[] = $yi;
}
for ($xi = $skip; $xi < $n_from - $endskip; $xi++) {
$line = $from_lines[$xi];
if (($this->xchanged[$xi] = empty($yhash[$line])))
continue;
$this->xv[] = $line;
$this->xind[] = $xi;
}
// Find the LCS.
$this->_compareseq(0, count($this->xv), 0, count($this->yv));
// Merge edits when possible
$this->_shift_boundaries($from_lines, $this->xchanged, $this->ychanged);
$this->_shift_boundaries($to_lines, $this->ychanged, $this->xchanged);
// Compute the edit operations.
$edits = array();
$xi = $yi = 0;
while ($xi < $n_from || $yi < $n_to) {
USE_ASSERTS && assert($yi < $n_to || $this->xchanged[$xi]);
USE_ASSERTS && assert($xi < $n_from || $this->ychanged[$yi]);
// Skip matching "snake".
$copy = array();
while ($xi < $n_from && $yi < $n_to && !$this->xchanged[$xi] && !$this->ychanged[$yi]) {
$copy[] = $from_lines[$xi++];
++$yi;
}
if ($copy)
$edits[] = new _DiffOp_Copy($copy);
// Find deletes & adds.
$delete = array();
while ($xi < $n_from && $this->xchanged[$xi])
$delete[] = $from_lines[$xi++];
$add = array();
while ($yi < $n_to && $this->ychanged[$yi])
$add[] = $to_lines[$yi++];
if ($delete && $add)
$edits[] = new _DiffOp_Change($delete, $add);
elseif ($delete)
$edits[] = new _DiffOp_Delete($delete);
elseif ($add)
$edits[] = new _DiffOp_Add($add);
}
return $edits;
}
/**
* Divide the Largest Common Subsequence (LCS) of the sequences
* [XOFF, XLIM) and [YOFF, YLIM) into NCHUNKS approximately equally
* sized segments.
*
* Returns (LCS, PTS). LCS is the length of the LCS. PTS is an
* array of NCHUNKS+1 (X, Y) indexes giving the diving points between
* sub sequences. The first sub-sequence is contained in [X0, X1),
* [Y0, Y1), the second in [X1, X2), [Y1, Y2) and so on. Note
* that (X0, Y0) == (XOFF, YOFF) and
* (X[NCHUNKS], Y[NCHUNKS]) == (XLIM, YLIM).
*
* This function assumes that the first lines of the specified portions
* of the two files do not match, and likewise that the last lines do not
* match. The caller must trim matching lines from the beginning and end
* of the portions it is going to specify.
*/
function _diag($xoff, $xlim, $yoff, $ylim, $nchunks) {
$flip = false;
if ($xlim - $xoff > $ylim - $yoff) {
// Things seems faster (I'm not sure I understand why)
// when the shortest sequence in X.
$flip = true;
list ($xoff, $xlim, $yoff, $ylim) = array($yoff, $ylim, $xoff, $xlim);
}
if ($flip)
for ($i = $ylim - 1; $i >= $yoff; $i--)
$ymatches[$this->xv[$i]][] = $i;
else
for ($i = $ylim - 1; $i >= $yoff; $i--)
$ymatches[$this->yv[$i]][] = $i;
$this->lcs = 0;
$this->seq[0]= $yoff - 1;
$this->in_seq = array();
$ymids[0] = array();
$numer = $xlim - $xoff + $nchunks - 1;
$x = $xoff;
for ($chunk = 0; $chunk < $nchunks; $chunk++) {
if ($chunk > 0)
for ($i = 0; $i <= $this->lcs; $i++)
$ymids[$i][$chunk-1] = $this->seq[$i];
$x1 = $xoff + (int)(($numer + ($xlim-$xoff)*$chunk) / $nchunks);
for ( ; $x < $x1; $x++) {
$line = $flip ? $this->yv[$x] : $this->xv[$x];
if (empty($ymatches[$line]))
continue;
$matches = $ymatches[$line];
reset($matches);
while (list ($junk, $y) = each($matches))
if (empty($this->in_seq[$y])) {
$k = $this->_lcs_pos($y);
USE_ASSERTS && assert($k > 0);
$ymids[$k] = $ymids[$k-1];
break;
}
while (list ($junk, $y) = each($matches)) {
if ($y > $this->seq[$k-1]) {
USE_ASSERTS && assert($y < $this->seq[$k]);
// Optimization: this is a common case:
// next match is just replacing previous match.
$this->in_seq[$this->seq[$k]] = false;
$this->seq[$k] = $y;
$this->in_seq[$y] = 1;
}
else if (empty($this->in_seq[$y])) {
$k = $this->_lcs_pos($y);
USE_ASSERTS && assert($k > 0);
$ymids[$k] = $ymids[$k-1];
}
}
}
}
$seps[] = $flip ? array($yoff, $xoff) : array($xoff, $yoff);
$ymid = $ymids[$this->lcs];
for ($n = 0; $n < $nchunks - 1; $n++) {
$x1 = $xoff + (int)(($numer + ($xlim - $xoff) * $n) / $nchunks);
$y1 = $ymid[$n] + 1;
$seps[] = $flip ? array($y1, $x1) : array($x1, $y1);
}
$seps[] = $flip ? array($ylim, $xlim) : array($xlim, $ylim);
return array($this->lcs, $seps);
}
function _lcs_pos($ypos) {
$end = $this->lcs;
if ($end == 0 || $ypos > $this->seq[$end]) {
$this->seq[++$this->lcs] = $ypos;
$this->in_seq[$ypos] = 1;
return $this->lcs;
}
$beg = 1;
while ($beg < $end) {
$mid = (int)(($beg + $end) / 2);
if ($ypos > $this->seq[$mid])
$beg = $mid + 1;
else
$end = $mid;
}
USE_ASSERTS && assert($ypos != $this->seq[$end]);
$this->in_seq[$this->seq[$end]] = false;
$this->seq[$end] = $ypos;
$this->in_seq[$ypos] = 1;
return $end;
}
/**
* Find LCS of two sequences.
*
* The results are recorded in the vectors $this->{x,y}changed[], by
* storing a 1 in the element for each line that is an insertion
* or deletion (ie. is not in the LCS).
*
* The subsequence of file 0 is [XOFF, XLIM) and likewise for file 1.
*
* Note that XLIM, YLIM are exclusive bounds.
* All line numbers are origin-0 and discarded lines are not counted.
*/
function _compareseq($xoff, $xlim, $yoff, $ylim) {
// Slide down the bottom initial diagonal.
while ($xoff < $xlim && $yoff < $ylim && $this->xv[$xoff] == $this->yv[$yoff]) {
++$xoff;
++$yoff;
}
// Slide up the top initial diagonal.
while ($xlim > $xoff && $ylim > $yoff && $this->xv[$xlim - 1] == $this->yv[$ylim - 1]) {
--$xlim;
--$ylim;
}
if ($xoff == $xlim || $yoff == $ylim)
$lcs = 0;
else {
// This is ad hoc but seems to work well.
//$nchunks = sqrt(min($xlim - $xoff, $ylim - $yoff) / 2.5);
//$nchunks = max(2,min(8,(int)$nchunks));
$nchunks = min(7, $xlim - $xoff, $ylim - $yoff) + 1;
list ($lcs, $seps)
= $this->_diag($xoff,$xlim,$yoff, $ylim,$nchunks);
}
if ($lcs == 0) {
// X and Y sequences have no common subsequence:
// mark all changed.
while ($yoff < $ylim)
$this->ychanged[$this->yind[$yoff++]] = 1;
while ($xoff < $xlim)
$this->xchanged[$this->xind[$xoff++]] = 1;
}
else {
// Use the partitions to split this problem into subproblems.
reset($seps);
$pt1 = $seps[0];
while ($pt2 = next($seps)) {
$this->_compareseq ($pt1[0], $pt2[0], $pt1[1], $pt2[1]);
$pt1 = $pt2;
}
}
}
/**
* Adjust inserts/deletes of identical lines to join changes
* as much as possible.
*
* We do something when a run of changed lines include a
* line at one end and has an excluded, identical line at the other.
* We are free to choose which identical line is included.
* `compareseq' usually chooses the one at the beginning,
* but usually it is cleaner to consider the following identical line
* to be the "change".
*
* This is extracted verbatim from analyze.c (GNU diffutils-2.7).
*/
function _shift_boundaries($lines, &$changed, $other_changed) {
$i = 0;
$j = 0;
USE_ASSERTS && assert('count($lines) == count($changed)');
$len = count($lines);
$other_len = count($other_changed);
while (1) {
/*
* Scan forwards to find beginning of another run of changes.
* Also keep track of the corresponding point in the other file.
*
* Throughout this code, $i and $j are adjusted together so that
* the first $i elements of $changed and the first $j elements
* of $other_changed both contain the same number of zeros
* (unchanged lines).
* Furthermore, $j is always kept so that $j == $other_len or
* $other_changed[$j] == false.
*/
while ($j < $other_len && $other_changed[$j])
$j++;
while ($i < $len && ! $changed[$i]) {
USE_ASSERTS && assert('$j < $other_len && ! $other_changed[$j]');
$i++;
$j++;
while ($j < $other_len && $other_changed[$j])
$j++;
}
if ($i == $len)
break;
$start = $i;
// Find the end of this run of changes.
while (++$i < $len && $changed[$i])
continue;
do {
/*
* Record the length of this run of changes, so that
* we can later determine whether the run has grown.
*/
$runlength = $i - $start;
/*
* Move the changed region back, so long as the
* previous unchanged line matches the last changed one.
* This merges with previous changed regions.
*/
while ($start > 0 && $lines[$start - 1] == $lines[$i - 1]) {
$changed[--$start] = 1;
$changed[--$i] = false;
while ($start > 0 && $changed[$start - 1])
$start--;
USE_ASSERTS && assert('$j > 0');
while ($other_changed[--$j])
continue;
USE_ASSERTS && assert('$j >= 0 && !$other_changed[$j]');
}
/*
* Set CORRESPONDING to the end of the changed run, at the last
* point where it corresponds to a changed run in the other file.
* CORRESPONDING == LEN means no such point has been found.
*/
$corresponding = $j < $other_len ? $i : $len;
/*
* Move the changed region forward, so long as the
* first changed line matches the following unchanged one.
* This merges with following changed regions.
* Do this second, so that if there are no merges,
* the changed region is moved forward as far as possible.
*/
while ($i < $len && $lines[$start] == $lines[$i]) {
$changed[$start++] = false;
$changed[$i++] = 1;
while ($i < $len && $changed[$i])
$i++;
USE_ASSERTS && assert('$j < $other_len && ! $other_changed[$j]');
$j++;
if ($j < $other_len && $other_changed[$j]) {
$corresponding = $i;
while ($j < $other_len && $other_changed[$j])
$j++;
}
}
} while ($runlength != $i - $start);
/*
* If possible, move the fully-merged run of changes
* back to a corresponding run in the other file.
*/
while ($corresponding < $i) {
$changed[--$start] = 1;
$changed[--$i] = 0;
USE_ASSERTS && assert('$j > 0');
while ($other_changed[--$j])
continue;
USE_ASSERTS && assert('$j >= 0 && !$other_changed[$j]');
}
}
}
}
/**
* Class representing a 'diff' between two sequences of strings.
*/
class Diff {
var $edits;
/**
* Constructor.
* Computes diff between sequences of strings.
*
* @param array $from_lines An array of strings.
* (Typically these are lines from a file.)
* @param array $to_lines An array of strings.
*/
function __construct($from_lines, $to_lines) {
$eng = new _DiffEngine;
$this->edits = $eng->diff($from_lines, $to_lines);
//$this->_check($from_lines, $to_lines);
}
/**
* Compute reversed Diff.
*
* SYNOPSIS:
*
* $diff = new Diff($lines1, $lines2);
* $rev = $diff->reverse();
*
* @return Diff A Diff object representing the inverse of the
* original diff.
*/
function reverse() {
$rev = $this;
$rev->edits = array();
foreach ($this->edits as $edit) {
$rev->edits[] = $edit->reverse();
}
return $rev;
}
/**
* Check for empty diff.
*
* @return bool True iff two sequences were identical.
*/
function isEmpty() {
foreach ($this->edits as $edit) {
if ($edit->type != 'copy')
return false;
}
return true;
}
/**
* Compute the length of the Longest Common Subsequence (LCS).
*
* This is mostly for diagnostic purposed.
*
* @return int The length of the LCS.
*/
function lcs() {
$lcs = 0;
foreach ($this->edits as $edit) {
if ($edit->type == 'copy')
$lcs += count($edit->orig);
}
return $lcs;
}
/**
* Get the original set of lines.
*
* This reconstructs the $from_lines parameter passed to the
* constructor.
*
* @return array The original sequence of strings.
*/
function orig() {
$lines = array();
foreach ($this->edits as $edit) {
if ($edit->orig)
array_splice($lines, count($lines), 0, $edit->orig);
}
return $lines;
}
/**
* Get the closing set of lines.
*
* This reconstructs the $to_lines parameter passed to the
* constructor.
*
* @return array The sequence of strings.
*/
function closing() {
$lines = array();
foreach ($this->edits as $edit) {
if ($edit->closing)
array_splice($lines, count($lines), 0, $edit->closing);
}
return $lines;
}
/**
* Check a Diff for validity.
*
* This is here only for debugging purposes.
*/
function _check($from_lines, $to_lines) {
if (serialize($from_lines) != serialize($this->orig()))
trigger_error("Reconstructed original doesn't match", E_USER_ERROR);
if (serialize($to_lines) != serialize($this->closing()))
trigger_error("Reconstructed closing doesn't match", E_USER_ERROR);
$rev = $this->reverse();
if (serialize($to_lines) != serialize($rev->orig()))
trigger_error("Reversed original doesn't match", E_USER_ERROR);
if (serialize($from_lines) != serialize($rev->closing()))
trigger_error("Reversed closing doesn't match", E_USER_ERROR);
$prevtype = 'none';
foreach ($this->edits as $edit) {
if ($prevtype == $edit->type)
trigger_error("Edit sequence is non-optimal", E_USER_ERROR);
$prevtype = $edit->type;
}
$lcs = $this->lcs();
trigger_error("Diff okay: LCS = $lcs", E_USER_NOTICE);
}
}
/**
* FIXME: bad name.
*/
class MappedDiff extends Diff {
/**
* Constructor.
*
* Computes diff between sequences of strings.
*
* This can be used to compute things like
* case-insensitve diffs, or diffs which ignore
* changes in white-space.
*
* @param string[] $from_lines An array of strings.
* (Typically these are lines from a file.)
*
* @param string[] $to_lines An array of strings.
*
* @param string[] $mapped_from_lines This array should
* have the same size number of elements as $from_lines.
* The elements in $mapped_from_lines and
* $mapped_to_lines are what is actually compared
* when computing the diff.
*
* @param string[] $mapped_to_lines This array should
* have the same number of elements as $to_lines.
*/
function __construct($from_lines, $to_lines, $mapped_from_lines, $mapped_to_lines) {
assert(count($from_lines) == count($mapped_from_lines));
assert(count($to_lines) == count($mapped_to_lines));
parent::__construct($mapped_from_lines, $mapped_to_lines);
$xi = $yi = 0;
$ecnt = count($this->edits);
for ($i = 0; $i < $ecnt; $i++) {
$orig = &$this->edits[$i]->orig;
if (is_array($orig)) {
$orig = array_slice($from_lines, $xi, count($orig));
$xi += count($orig);
}
$closing = &$this->edits[$i]->closing;
if (is_array($closing)) {
$closing = array_slice($to_lines, $yi, count($closing));
$yi += count($closing);
}
}
}
}
/**
* A class to format Diffs
*
* This class formats the diff in classic diff format.
* It is intended that this class be customized via inheritance,
* to obtain fancier outputs.
*/
class DiffFormatter {
/**
* 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;
/**
* Format a diff.
*
* @param Diff $diff A Diff object.
* @return string The formatted output.
*/
function format($diff) {
$xi = $yi = 1;
$x0 = $y0 = 0;
$block = false;
$context = array();
$nlead = $this->leading_context_lines;
$ntrail = $this->trailing_context_lines;
$this->_start_diff();
foreach ($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);
$block[] = new _DiffOp_Copy($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)
$block[] = new _DiffOp_Copy($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);
return $this->_end_diff();
}
/**
* @param int $xbeg
* @param int $xlen
* @param int $ybeg
* @param int $ylen
* @param array $edits
*/
function _block($xbeg, $xlen, $ybeg, $ylen, &$edits) {
$this->_start_block($this->_block_header($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
trigger_error("Unknown edit type", E_USER_ERROR);
}
$this->_end_block();
}
function _start_diff() {
ob_start();
}
function _end_diff() {
$val = ob_get_contents();
ob_end_clean();
return $val;
}
/**
* @param int $xbeg
* @param int $xlen
* @param int $ybeg
* @param int $ylen
* @return string
*/
function _block_header($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;
}
/**
* @param string $header
*/
function _start_block($header) {
echo $header;
}
function _end_block() {
}
function _lines($lines, $prefix = ' ') {
foreach ($lines as $line)
echo "$prefix ".$this->_escape($line)."\n";
}
function _context($lines) {
$this->_lines($lines);
}
function _added($lines) {
$this->_lines($lines, ">");
}
function _deleted($lines) {
$this->_lines($lines, "<");
}
function _changed($orig, $closing) {
$this->_deleted($orig);
echo "---\n";
$this->_added($closing);
}
/**
* Escape string
*
* Override this method within other formatters if escaping required.
* Base class requires $str to be returned WITHOUT escaping.
*
* @param $str string Text string to escape
* @return string The escaped string.
*/
function _escape($str){
return $str;
}
}
/**
* Utilityclass for styling HTML formatted diffs
*
* Depends on global var $DIFF_INLINESTYLES, if true some minimal predefined
* inline styles are used. Useful for HTML mails and RSS feeds
*
* @author Andreas Gohr <andi@splitbrain.org>
*/
class HTMLDiff {
/**
* Holds the style names and basic CSS
*/
static public $styles = array(
'diff-addedline' => 'background-color: #ddffdd;',
'diff-deletedline' => 'background-color: #ffdddd;',
'diff-context' => 'background-color: #f5f5f5;',
'diff-mark' => 'color: #ff0000;',
);
/**
* Return a class or style parameter
*/
static function css($classname){
global $DIFF_INLINESTYLES;
if($DIFF_INLINESTYLES){
if(!isset(self::$styles[$classname])) return '';
return 'style="'.self::$styles[$classname].'"';
}else{
return 'class="'.$classname.'"';
}
}
}
/**
* Additions by Axel Boldt follow, partly taken from diff.php, phpwiki-1.3.3
*
*/
define('NBSP', "\xC2\xA0"); // utf-8 non-breaking space.
class _HWLDF_WordAccumulator {
function __construct() {
$this->_lines = array();
$this->_line = '';
$this->_group = '';
$this->_tag = '';
}
function _flushGroup($new_tag) {
if ($this->_group !== '') {
if ($this->_tag == 'mark')
$this->_line .= '<strong '.HTMLDiff::css('diff-mark').'>'.$this->_escape($this->_group).'</strong>';
elseif ($this->_tag == 'add')
$this->_line .= '<span '.HTMLDiff::css('diff-addedline').'>'.$this->_escape($this->_group).'</span>';
elseif ($this->_tag == 'del')
$this->_line .= '<span '.HTMLDiff::css('diff-deletedline').'><del>'.$this->_escape($this->_group).'</del></span>';
else
$this->_line .= $this->_escape($this->_group);
}
$this->_group = '';
$this->_tag = $new_tag;
}
/**
* @param string $new_tag
*/
function _flushLine($new_tag) {
$this->_flushGroup($new_tag);
if ($this->_line != '')
$this->_lines[] = $this->_line;
$this->_line = '';
}
function addWords($words, $tag = '') {
if ($tag != $this->_tag)
$this->_flushGroup($tag);
foreach ($words as $word) {
// new-line should only come as first char of word.
if ($word == '')
continue;
if ($word[0] == "\n") {
$this->_group .= NBSP;
$this->_flushLine($tag);
$word = substr($word, 1);
}
assert(!strstr($word, "\n"));
$this->_group .= $word;
}
}
function getLines() {
$this->_flushLine('~done');
return $this->_lines;
}
function _escape($str){
return hsc($str);
}
}
class WordLevelDiff extends MappedDiff {
function __construct($orig_lines, $closing_lines) {
list ($orig_words, $orig_stripped) = $this->_split($orig_lines);
list ($closing_words, $closing_stripped) = $this->_split($closing_lines);
parent::__construct($orig_words, $closing_words, $orig_stripped, $closing_stripped);
}
function _split($lines) {
if (!preg_match_all('/ ( [^\S\n]+ | [0-9_A-Za-z\x80-\xff]+ | . ) (?: (?!< \n) [^\S\n])? /xsu',
implode("\n", $lines), $m)) {
return array(array(''), array(''));
}
return array($m[0], $m[1]);
}
function orig() {
$orig = new _HWLDF_WordAccumulator;
foreach ($this->edits as $edit) {
if ($edit->type == 'copy')
$orig->addWords($edit->orig);
elseif ($edit->orig)
$orig->addWords($edit->orig, 'mark');
}
return $orig->getLines();
}
function closing() {
$closing = new _HWLDF_WordAccumulator;
foreach ($this->edits as $edit) {
if ($edit->type == 'copy')
$closing->addWords($edit->closing);
elseif ($edit->closing)
$closing->addWords($edit->closing, 'mark');
}
return $closing->getLines();
}
}
class InlineWordLevelDiff extends MappedDiff {
function __construct($orig_lines, $closing_lines) {
list ($orig_words, $orig_stripped) = $this->_split($orig_lines);
list ($closing_words, $closing_stripped) = $this->_split($closing_lines);
parent::__construct($orig_words, $closing_words, $orig_stripped, $closing_stripped);
}
function _split($lines) {
if (!preg_match_all('/ ( [^\S\n]+ | [0-9_A-Za-z\x80-\xff]+ | . ) (?: (?!< \n) [^\S\n])? /xsu',
implode("\n", $lines), $m)) {
return array(array(''), array(''));
}
return array($m[0], $m[1]);
}
function inline() {
$orig = new _HWLDF_WordAccumulator;
foreach ($this->edits as $edit) {
if ($edit->type == 'copy')
$orig->addWords($edit->closing);
elseif ($edit->type == 'change'){
$orig->addWords($edit->orig, 'del');
$orig->addWords($edit->closing, 'add');
} elseif ($edit->type == 'delete')
$orig->addWords($edit->orig, 'del');
elseif ($edit->type == 'add')
$orig->addWords($edit->closing, 'add');
elseif ($edit->orig)
$orig->addWords($edit->orig, 'del');
}
return $orig->getLines();
}
}
/**
* "Unified" diff formatter.
*
* This class formats the diff in classic "unified diff" format.
*
* NOTE: output is plain text and unsafe for use in HTML without escaping.
*/
class UnifiedDiffFormatter extends DiffFormatter {
function __construct($context_lines = 4) {
$this->leading_context_lines = $context_lines;
$this->trailing_context_lines = $context_lines;
}
function _block_header($xbeg, $xlen, $ybeg, $ylen) {
if ($xlen != 1)
$xbeg .= "," . $xlen;
if ($ylen != 1)
$ybeg .= "," . $ylen;
return "@@ -$xbeg +$ybeg @@\n";
}
function _added($lines) {
$this->_lines($lines, "+");
}
function _deleted($lines) {
$this->_lines($lines, "-");
}
function _changed($orig, $final) {
$this->_deleted($orig);
$this->_added($final);
}
}
/**
* Wikipedia Table style diff formatter.
*
*/
class TableDiffFormatter extends DiffFormatter {
var $colspan = 2;
function __construct() {
$this->leading_context_lines = 2;
$this->trailing_context_lines = 2;
}
/**
* @param Diff $diff
* @return string
*/
function format($diff) {
// Preserve whitespaces by converting some to non-breaking spaces.
// Do not convert all of them to allow word-wrap.
$val = parent::format($diff);
$val = str_replace(' ','&#160; ', $val);
$val = preg_replace('/ (?=<)|(?<=[ >]) /', '&#160;', $val);
return $val;
}
function _pre($text){
$text = htmlspecialchars($text);
return $text;
}
function _block_header($xbeg, $xlen, $ybeg, $ylen) {
global $lang;
$l1 = $lang['line'].' '.$xbeg;
$l2 = $lang['line'].' '.$ybeg;
$r = '<tr><td '.HTMLDiff::css('diff-blockheader').' colspan="'.$this->colspan.'">'.$l1.":</td>\n".
'<td '.HTMLDiff::css('diff-blockheader').' colspan="'.$this->colspan.'">'.$l2.":</td>\n".
"</tr>\n";
return $r;
}
function _start_block($header) {
print($header);
}
function _end_block() {
}
function _lines($lines, $prefix=' ', $color="white") {
}
function addedLine($line,$escaped=false) {
if (!$escaped){
$line = $this->_escape($line);
}
return '<td '.HTMLDiff::css('diff-lineheader').'>+</td>'.
'<td '.HTMLDiff::css('diff-addedline').'>' . $line.'</td>';
}
function deletedLine($line,$escaped=false) {
if (!$escaped){
$line = $this->_escape($line);
}
return '<td '.HTMLDiff::css('diff-lineheader').'>-</td>'.
'<td '.HTMLDiff::css('diff-deletedline').'>' . $line.'</td>';
}
function emptyLine() {
return '<td colspan="'.$this->colspan.'">&#160;</td>';
}
function contextLine($line) {
return '<td '.HTMLDiff::css('diff-lineheader').'>&#160;</td>'.
'<td '.HTMLDiff::css('diff-context').'>'.$this->_escape($line).'</td>';
}
function _added($lines) {
$this->_addedLines($lines,false);
}
function _addedLines($lines,$escaped=false){
foreach ($lines as $line) {
print('<tr>' . $this->emptyLine() . $this->addedLine($line,$escaped) . "</tr>\n");
}
}
function _deleted($lines) {
foreach ($lines as $line) {
print('<tr>' . $this->deletedLine($line) . $this->emptyLine() . "</tr>\n");
}
}
function _context($lines) {
foreach ($lines as $line) {
print('<tr>' . $this->contextLine($line) . $this->contextLine($line) . "</tr>\n");
}
}
function _changed($orig, $closing) {
$diff = new WordLevelDiff($orig, $closing); // this escapes the diff data
$del = $diff->orig();
$add = $diff->closing();
while ($line = array_shift($del)) {
$aline = array_shift($add);
print('<tr>' . $this->deletedLine($line,true) . $this->addedLine($aline,true) . "</tr>\n");
}
$this->_addedLines($add,true); # If any leftovers
}
function _escape($str) {
return hsc($str);
}
}
/**
* Inline style diff formatter.
*
*/
class InlineDiffFormatter extends DiffFormatter {
var $colspan = 2;
function __construct() {
$this->leading_context_lines = 2;
$this->trailing_context_lines = 2;
}
/**
* @param Diff $diff
* @return string
*/
function format($diff) {
// Preserve whitespaces by converting some to non-breaking spaces.
// Do not convert all of them to allow word-wrap.
$val = parent::format($diff);
$val = str_replace(' ','&#160; ', $val);
$val = preg_replace('/ (?=<)|(?<=[ >]) /', '&#160;', $val);
return $val;
}
function _pre($text){
$text = htmlspecialchars($text);
return $text;
}
function _block_header($xbeg, $xlen, $ybeg, $ylen) {
global $lang;
if ($xlen != 1)
$xbeg .= "," . $xlen;
if ($ylen != 1)
$ybeg .= "," . $ylen;
$r = '<tr><td colspan="'.$this->colspan.'" '.HTMLDiff::css('diff-blockheader').'>@@ '.$lang['line']." -$xbeg +$ybeg @@";
$r .= ' <span '.HTMLDiff::css('diff-deletedline').'><del>'.$lang['deleted'].'</del></span>';
$r .= ' <span '.HTMLDiff::css('diff-addedline').'>'.$lang['created'].'</span>';
$r .= "</td></tr>\n";
return $r;
}
function _start_block($header) {
print($header."\n");
}
function _end_block() {
}
function _lines($lines, $prefix=' ', $color="white") {
}
function _added($lines) {
foreach ($lines as $line) {
print('<tr><td '.HTMLDiff::css('diff-lineheader').'>&#160;</td><td '.HTMLDiff::css('diff-addedline').'>'. $this->_escape($line) . "</td></tr>\n");
}
}
function _deleted($lines) {
foreach ($lines as $line) {
print('<tr><td '.HTMLDiff::css('diff-lineheader').'>&#160;</td><td '.HTMLDiff::css('diff-deletedline').'><del>' . $this->_escape($line) . "</del></td></tr>\n");
}
}
function _context($lines) {
foreach ($lines as $line) {
print('<tr><td '.HTMLDiff::css('diff-lineheader').'>&#160;</td><td '.HTMLDiff::css('diff-context').'>'. $this->_escape($line) ."</td></tr>\n");
}
}
function _changed($orig, $closing) {
$diff = new InlineWordLevelDiff($orig, $closing); // this escapes the diff data
$add = $diff->inline();
foreach ($add as $line)
print('<tr><td '.HTMLDiff::css('diff-lineheader').'>&#160;</td><td>'.$line."</td></tr>\n");
}
function _escape($str) {
return hsc($str);
}
}
/**
* A class for computing three way diffs.
*
* @author Geoffrey T. Dairiki <dairiki@dairiki.org>
*/
class Diff3 extends Diff {
/**
* Conflict counter.
*
* @var integer
*/
var $_conflictingBlocks = 0;
/**
* Computes diff between 3 sequences of strings.
*
* @param array $orig The original lines to use.
* @param array $final1 The first version to compare to.
* @param array $final2 The second version to compare to.
*/
function __construct($orig, $final1, $final2) {
$engine = new _DiffEngine();
$this->_edits = $this->_diff3($engine->diff($orig, $final1),
$engine->diff($orig, $final2));
}
/**
* Returns the merged lines
*
* @param string $label1 label for first version
* @param string $label2 label for second version
* @param string $label3 separator between versions
* @return array lines of the merged text
*/
function mergedOutput($label1='<<<<<<<',$label2='>>>>>>>',$label3='=======') {
$lines = array();
foreach ($this->_edits as $edit) {
if ($edit->isConflict()) {
/* FIXME: this should probably be moved somewhere else. */
$lines = array_merge($lines,
array($label1),
$edit->final1,
array($label3),
$edit->final2,
array($label2));
$this->_conflictingBlocks++;
} else {
$lines = array_merge($lines, $edit->merged());
}
}
return $lines;
}
/**
* @access private
*/
function _diff3($edits1, $edits2) {
$edits = array();
$bb = new _Diff3_BlockBuilder();
$e1 = current($edits1);
$e2 = current($edits2);
while ($e1 || $e2) {
if ($e1 && $e2 && is_a($e1, '_DiffOp_copy') && is_a($e2, '_DiffOp_copy')) {
/* We have copy blocks from both diffs. This is the (only)
* time we want to emit a diff3 copy block. Flush current
* diff3 diff block, if any. */
if ($edit = $bb->finish()) {
$edits[] = $edit;
}
$ncopy = min($e1->norig(), $e2->norig());
assert($ncopy > 0);
$edits[] = new _Diff3_Op_copy(array_slice($e1->orig, 0, $ncopy));
if ($e1->norig() > $ncopy) {
array_splice($e1->orig, 0, $ncopy);
array_splice($e1->closing, 0, $ncopy);
} else {
$e1 = next($edits1);
}
if ($e2->norig() > $ncopy) {
array_splice($e2->orig, 0, $ncopy);
array_splice($e2->closing, 0, $ncopy);
} else {
$e2 = next($edits2);
}
} else {
if ($e1 && $e2) {
if ($e1->orig && $e2->orig) {
$norig = min($e1->norig(), $e2->norig());
$orig = array_splice($e1->orig, 0, $norig);
array_splice($e2->orig, 0, $norig);
$bb->input($orig);
}
if (is_a($e1, '_DiffOp_copy')) {
$bb->out1(array_splice($e1->closing, 0, $norig));
}
if (is_a($e2, '_DiffOp_copy')) {
$bb->out2(array_splice($e2->closing, 0, $norig));
}
}
if ($e1 && ! $e1->orig) {
$bb->out1($e1->closing);
$e1 = next($edits1);
}
if ($e2 && ! $e2->orig) {
$bb->out2($e2->closing);
$e2 = next($edits2);
}
}
}
if ($edit = $bb->finish()) {
$edits[] = $edit;
}
return $edits;
}
}
/**
* @author Geoffrey T. Dairiki <dairiki@dairiki.org>
*
* @access private
*/
class _Diff3_Op {
function __construct($orig = false, $final1 = false, $final2 = false) {
$this->orig = $orig ? $orig : array();
$this->final1 = $final1 ? $final1 : array();
$this->final2 = $final2 ? $final2 : array();
}
function merged() {
if (!isset($this->_merged)) {
if ($this->final1 === $this->final2) {
$this->_merged = &$this->final1;
} elseif ($this->final1 === $this->orig) {
$this->_merged = &$this->final2;
} elseif ($this->final2 === $this->orig) {
$this->_merged = &$this->final1;
} else {
$this->_merged = false;
}
}
return $this->_merged;
}
function isConflict() {
return $this->merged() === false;
}
}
/**
* @author Geoffrey T. Dairiki <dairiki@dairiki.org>
*
* @access private
*/
class _Diff3_Op_copy extends _Diff3_Op {
function __construct($lines = false) {
$this->orig = $lines ? $lines : array();
$this->final1 = &$this->orig;
$this->final2 = &$this->orig;
}
function merged() {
return $this->orig;
}
function isConflict() {
return false;
}
}
/**
* @author Geoffrey T. Dairiki <dairiki@dairiki.org>
*
* @access private
*/
class _Diff3_BlockBuilder {
function __construct() {
$this->_init();
}
function input($lines) {
if ($lines) {
$this->_append($this->orig, $lines);
}
}
function out1($lines) {
if ($lines) {
$this->_append($this->final1, $lines);
}
}
function out2($lines) {
if ($lines) {
$this->_append($this->final2, $lines);
}
}
function isEmpty() {
return !$this->orig && !$this->final1 && !$this->final2;
}
function finish() {
if ($this->isEmpty()) {
return false;
} else {
$edit = new _Diff3_Op($this->orig, $this->final1, $this->final2);
$this->_init();
return $edit;
}
}
function _init() {
$this->orig = $this->final1 = $this->final2 = array();
}
function _append(&$array, $lines) {
array_splice($array, sizeof($array), 0, $lines);
}
}
//Setup VIM: ex: et ts=4 :