From ca32f08966f1b51fcb19460f0996bb0c4048e6fe Mon Sep 17 00:00:00 2001 From: Pierre Schmitz Date: Sat, 3 Dec 2011 13:29:22 +0100 Subject: Update to MediaWiki 1.18.0 * also update ArchLinux skin to chagnes in MonoBook * Use only css to hide our menu bar when printing --- includes/diff/DairikiDiff.php | 1295 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 1295 insertions(+) create mode 100644 includes/diff/DairikiDiff.php (limited to 'includes/diff/DairikiDiff.php') diff --git a/includes/diff/DairikiDiff.php b/includes/diff/DairikiDiff.php new file mode 100644 index 00000000..8f19712b --- /dev/null +++ b/includes/diff/DairikiDiff.php @@ -0,0 +1,1295 @@ + + * You may copy this code freely under the conditions of the GPL. + * + * @file + * @ingroup DifferenceEngine + * @defgroup DifferenceEngine DifferenceEngine + */ + +/** + * @todo document + * @private + * @ingroup DifferenceEngine + */ +class _DiffOp { + var $type; + var $orig; + var $closing; + + function reverse() { + trigger_error( 'pure virtual', E_USER_ERROR ); + } + + function norig() { + return $this->orig ? sizeof( $this->orig ) : 0; + } + + function nclosing() { + return $this->closing ? sizeof( $this->closing ) : 0; + } +} + +/** + * @todo document + * @private + * @ingroup DifferenceEngine + */ +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 ); + } +} + +/** + * @todo document + * @private + * @ingroup DifferenceEngine + */ +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 ); + } +} + +/** + * @todo document + * @private + * @ingroup DifferenceEngine + */ +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 ); + } +} + +/** + * @todo document + * @private + * @ingroup DifferenceEngine + */ +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. + * + * Line length limits for robustness added by Tim Starling, 2005-08-31 + * Alternative implementation added by Guy Van den Broeck, 2008-07-30 + * + * @author Geoffrey T. Dairiki, Tim Starling, Guy Van den Broeck + * @private + * @ingroup DifferenceEngine + */ +class _DiffEngine { + + const MAX_XREF_LENGTH = 10000; + + protected $xchanged, $ychanged; + + protected $xv = array(), $yv = array(); + protected $xind = array(), $yind = array(); + + protected $seq = array(), $in_seq = array(); + + protected $lcs = 0; + + function diff ( $from_lines, $to_lines ) { + wfProfileIn( __METHOD__ ); + + // Diff and store locally + $this->diff_local( $from_lines, $to_lines ); + + // 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. + $n_from = sizeof( $from_lines ); + $n_to = sizeof( $to_lines ); + + $edits = array(); + $xi = $yi = 0; + while ( $xi < $n_from || $yi < $n_to ) { + assert( $yi < $n_to || $this->xchanged[$xi] ); + 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 ); + } + } + wfProfileOut( __METHOD__ ); + return $edits; + } + + function diff_local ( $from_lines, $to_lines ) { + global $wgExternalDiffEngine; + wfProfileIn( __METHOD__ ); + + if ( $wgExternalDiffEngine == 'wikidiff3' ) { + // wikidiff3 + $wikidiff3 = new WikiDiff3(); + $wikidiff3->diff( $from_lines, $to_lines ); + $this->xchanged = $wikidiff3->removed; + $this->ychanged = $wikidiff3->added; + unset( $wikidiff3 ); + } else { + // old diff + $n_from = sizeof( $from_lines ); + $n_to = sizeof( $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++ ) { + $xhash[$this->_line_hash( $from_lines[$xi] )] = 1; + } + + for ( $yi = $skip; $yi < $n_to - $endskip; $yi++ ) { + $line = $to_lines[$yi]; + if ( ( $this->ychanged[$yi] = empty( $xhash[$this->_line_hash( $line )] ) ) ) { + continue; + } + $yhash[$this->_line_hash( $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( $yhash[$this->_line_hash( $line )] ) ) ) { + continue; + } + $this->xv[] = $line; + $this->xind[] = $xi; + } + + // Find the LCS. + $this->_compareseq( 0, sizeof( $this->xv ), 0, sizeof( $this->yv ) ); + } + wfProfileOut( __METHOD__ ); + } + + /** + * Returns the whole line if it's small enough, or the MD5 hash otherwise + */ + function _line_hash( $line ) { + if ( strlen( $line ) > self::MAX_XREF_LENGTH ) { + return md5( $line ); + } else { + return $line; + } + } + + /** + * 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( , $y ) = each( $matches ) ) { + if ( empty( $this->in_seq[$y] ) ) { + $k = $this->_lcs_pos( $y ); + assert( $k > 0 ); + $ymids[$k] = $ymids[$k -1]; + break; + } + } + while ( list ( , $y ) = each( $matches ) ) { + if ( $y > $this->seq[$k -1] ) { + 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; + } elseif ( empty( $this->in_seq[$y] ) ) { + $k = $this->_lcs_pos( $y ); + 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; + } + } + + 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 ) { + wfProfileIn( __METHOD__ ); + $i = 0; + $j = 0; + + assert( 'sizeof($lines) == sizeof($changed)' ); + $len = sizeof( $lines ); + $other_len = sizeof( $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] ) { + 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] ) { + $start--; + } + assert( '$j > 0' ); + while ( $other_changed[--$j] ) { + continue; + } + 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] ) { + $i++; + } + + assert( '$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; + assert( '$j > 0' ); + while ( $other_changed[--$j] ) { + continue; + } + assert( '$j >= 0 && !$other_changed[$j]' ); + } + } + wfProfileOut( __METHOD__ ); + } +} + +/** + * Class representing a 'diff' between two sequences of strings. + * @todo document + * @private + * @ingroup DifferenceEngine + */ +class Diff { + var $edits; + + /** + * Constructor. + * Computes diff between sequences of strings. + * + * @param $from_lines array An array of strings. + * (Typically these are lines from a file.) + * @param $to_lines array 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 object 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 += sizeof( $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, sizeof( $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, sizeof( $lines ), 0, $edit->closing ); + } + } + return $lines; + } + + /** + * Check a Diff for validity. + * + * This is here only for debugging purposes. + */ + function _check( $from_lines, $to_lines ) { + wfProfileIn( __METHOD__ ); + 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 ); + wfProfileOut( __METHOD__ ); + } +} + +/** + * @todo document, bad name. + * @private + * @ingroup DifferenceEngine + */ +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 $from_lines array An array of strings. + * (Typically these are lines from a file.) + * + * @param $to_lines array An array of strings. + * + * @param $mapped_from_lines array 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 $mapped_to_lines array This array should + * have the same number of elements as $to_lines. + */ + function __construct( $from_lines, $to_lines, + $mapped_from_lines, $mapped_to_lines ) { + wfProfileIn( __METHOD__ ); + + assert( sizeof( $from_lines ) == sizeof( $mapped_from_lines ) ); + assert( sizeof( $to_lines ) == sizeof( $mapped_to_lines ) ); + + parent::__construct( $mapped_from_lines, $mapped_to_lines ); + + $xi = $yi = 0; + for ( $i = 0; $i < sizeof( $this->edits ); $i++ ) { + $orig = &$this->edits[$i]->orig; + if ( is_array( $orig ) ) { + $orig = array_slice( $from_lines, $xi, sizeof( $orig ) ); + $xi += sizeof( $orig ); + } + + $closing = &$this->edits[$i]->closing; + if ( is_array( $closing ) ) { + $closing = array_slice( $to_lines, $yi, sizeof( $closing ) ); + $yi += sizeof( $closing ); + } + } + wfProfileOut( __METHOD__ ); + } +} + +/** + * 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. + * @todo document + * @private + * @ingroup DifferenceEngine + */ +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 ) { + wfProfileIn( __METHOD__ ); + + $xi = $yi = 1; + $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 ( sizeof( $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, sizeof( $context ) - $nlead ); + $x0 = $xi - sizeof( $context ); + $y0 = $yi - sizeof( $context ); + $block = array(); + if ( $context ) { + $block[] = new _DiffOp_Copy( $context ); + } + } + $block[] = $edit; + } + + if ( $edit->orig ) { + $xi += sizeof( $edit->orig ); + } + if ( $edit->closing ) { + $yi += sizeof( $edit->closing ); + } + } + + if ( is_array( $block ) ) { + $this->_block( $x0, $xi - $x0, + $y0, $yi - $y0, + $block ); + } + + $end = $this->_end_diff(); + wfProfileOut( __METHOD__ ); + return $end; + } + + function _block( $xbeg, $xlen, $ybeg, $ylen, &$edits ) { + wfProfileIn( __METHOD__ ); + $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(); + wfProfileOut( __METHOD__ ); + } + + function _start_diff() { + ob_start(); + } + + function _end_diff() { + $val = ob_get_contents(); + ob_end_clean(); + return $val; + } + + 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; + } + + function _start_block( $header ) { + echo $header . "\n"; + } + + function _end_block() { + } + + function _lines( $lines, $prefix = ' ' ) { + foreach ( $lines as $line ) { + echo "$prefix $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 ); + } +} + +/** + * A formatter that outputs unified diffs + * @ingroup DifferenceEngine + */ +class UnifiedDiffFormatter extends DiffFormatter { + var $leading_context_lines = 2; + var $trailing_context_lines = 2; + + function _added( $lines ) { + $this->_lines( $lines, '+' ); + } + function _deleted( $lines ) { + $this->_lines( $lines, '-' ); + } + function _changed( $orig, $closing ) { + $this->_deleted( $orig ); + $this->_added( $closing ); + } + function _block_header( $xbeg, $xlen, $ybeg, $ylen ) { + return "@@ -$xbeg,$xlen +$ybeg,$ylen @@"; + } +} + +/** + * A pseudo-formatter that just passes along the Diff::$edits array + * @ingroup DifferenceEngine + */ +class ArrayDiffFormatter extends DiffFormatter { + function format( $diff ) { + $oldline = 1; + $newline = 1; + $retval = array(); + foreach ( $diff->edits as $edit ) { + switch( $edit->type ) { + case 'add': + foreach ( $edit->closing as $l ) { + $retval[] = array( + 'action' => 'add', + 'new' => $l, + 'newline' => $newline++ + ); + } + break; + case 'delete': + foreach ( $edit->orig as $l ) { + $retval[] = array( + 'action' => 'delete', + 'old' => $l, + 'oldline' => $oldline++, + ); + } + break; + case 'change': + foreach ( $edit->orig as $i => $l ) { + $retval[] = array( + 'action' => 'change', + 'old' => $l, + 'new' => isset( $edit->closing[$i] ) ? $edit->closing[$i] : null, + 'oldline' => $oldline++, + 'newline' => $newline++, + ); + } + break; + case 'copy': + $oldline += count( $edit->orig ); + $newline += count( $edit->orig ); + } + } + return $retval; + } +} + +/** + * Additions by Axel Boldt follow, partly taken from diff.php, phpwiki-1.3.3 + */ + +define( 'NBSP', ' ' ); // iso-8859-x non-breaking space. + +/** + * @todo document + * @private + * @ingroup DifferenceEngine + */ +class _HWLDF_WordAccumulator { + function __construct() { + $this->_lines = array(); + $this->_line = ''; + $this->_group = ''; + $this->_tag = ''; + } + + function _flushGroup( $new_tag ) { + if ( $this->_group !== '' ) { + if ( $this->_tag == 'ins' ) { + $this->_line .= '' . + htmlspecialchars( $this->_group ) . ''; + } elseif ( $this->_tag == 'del' ) { + $this->_line .= '' . + htmlspecialchars( $this->_group ) . ''; + } else { + $this->_line .= htmlspecialchars( $this->_group ); + } + } + $this->_group = ''; + $this->_tag = $new_tag; + } + + function _flushLine( $new_tag ) { + $this->_flushGroup( $new_tag ); + if ( $this->_line != '' ) { + array_push( $this->_lines, $this->_line ); + } else { + # make empty lines visible by inserting an NBSP + array_push( $this->_lines, NBSP ); + } + $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->_flushLine( $tag ); + $word = substr( $word, 1 ); + } + assert( !strstr( $word, "\n" ) ); + $this->_group .= $word; + } + } + + function getLines() { + $this->_flushLine( '~done' ); + return $this->_lines; + } +} + +/** + * @todo document + * @private + * @ingroup DifferenceEngine + */ +class WordLevelDiff extends MappedDiff { + const MAX_LINE_LENGTH = 10000; + + function __construct ( $orig_lines, $closing_lines ) { + wfProfileIn( __METHOD__ ); + + 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 ); + wfProfileOut( __METHOD__ ); + } + + function _split( $lines ) { + wfProfileIn( __METHOD__ ); + + $words = array(); + $stripped = array(); + $first = true; + foreach ( $lines as $line ) { + # If the line is too long, just pretend the entire line is one big word + # This prevents resource exhaustion problems + if ( $first ) { + $first = false; + } else { + $words[] = "\n"; + $stripped[] = "\n"; + } + if ( strlen( $line ) > self::MAX_LINE_LENGTH ) { + $words[] = $line; + $stripped[] = $line; + } else { + $m = array(); + if ( preg_match_all( '/ ( [^\S\n]+ | [0-9_A-Za-z\x80-\xff]+ | . ) (?: (?!< \n) [^\S\n])? /xs', + $line, $m ) ) + { + $words = array_merge( $words, $m[0] ); + $stripped = array_merge( $stripped, $m[1] ); + } + } + } + wfProfileOut( __METHOD__ ); + return array( $words, $stripped ); + } + + function orig() { + wfProfileIn( __METHOD__ ); + $orig = new _HWLDF_WordAccumulator; + + foreach ( $this->edits as $edit ) { + if ( $edit->type == 'copy' ) { + $orig->addWords( $edit->orig ); + } elseif ( $edit->orig ) { + $orig->addWords( $edit->orig, 'del' ); + } + } + $lines = $orig->getLines(); + wfProfileOut( __METHOD__ ); + return $lines; + } + + function closing() { + wfProfileIn( __METHOD__ ); + $closing = new _HWLDF_WordAccumulator; + + foreach ( $this->edits as $edit ) { + if ( $edit->type == 'copy' ) { + $closing->addWords( $edit->closing ); + } elseif ( $edit->closing ) { + $closing->addWords( $edit->closing, 'ins' ); + } + } + $lines = $closing->getLines(); + wfProfileOut( __METHOD__ ); + return $lines; + } +} + +/** + * Wikipedia Table style diff formatter. + * @todo document + * @private + * @ingroup DifferenceEngine + */ +class TableDiffFormatter extends DiffFormatter { + function __construct() { + $this->leading_context_lines = 2; + $this->trailing_context_lines = 2; + } + + public static function escapeWhiteSpace( $msg ) { + $msg = preg_replace( '/^ /m', '  ', $msg ); + $msg = preg_replace( '/ $/m', '  ', $msg ); + $msg = preg_replace( '/ /', '  ', $msg ); + return $msg; + } + + function _block_header( $xbeg, $xlen, $ybeg, $ylen ) { + $r = '\n" . + '\n"; + return $r; + } + + function _start_block( $header ) { + echo $header; + } + + function _end_block() { + } + + function _lines( $lines, $prefix = ' ', $color = 'white' ) { + } + + # HTML-escape parameter before calling this + function addedLine( $line ) { + return $this->wrapLine( '+', 'diff-addedline', $line ); + } + + # HTML-escape parameter before calling this + function deletedLine( $line ) { + return $this->wrapLine( '−', 'diff-deletedline', $line ); + } + + # HTML-escape parameter before calling this + function contextLine( $line ) { + return $this->wrapLine( ' ', 'diff-context', $line ); + } + + private function wrapLine( $marker, $class, $line ) { + if ( $line !== '' ) { + // The
wrapper is needed for 'overflow: auto' style to scroll properly + $line = Xml::tags( 'div', null, $this->escapeWhiteSpace( $line ) ); + } + return "$marker$line"; + } + + function emptyLine() { + return ' '; + } + + function _added( $lines ) { + foreach ( $lines as $line ) { + echo '' . $this->emptyLine() . + $this->addedLine( '' . + htmlspecialchars( $line ) . '' ) . "\n"; + } + } + + function _deleted( $lines ) { + foreach ( $lines as $line ) { + echo '' . $this->deletedLine( '' . + htmlspecialchars( $line ) . '' ) . + $this->emptyLine() . "\n"; + } + } + + function _context( $lines ) { + foreach ( $lines as $line ) { + echo '' . + $this->contextLine( htmlspecialchars( $line ) ) . + $this->contextLine( htmlspecialchars( $line ) ) . "\n"; + } + } + + function _changed( $orig, $closing ) { + wfProfileIn( __METHOD__ ); + + $diff = new WordLevelDiff( $orig, $closing ); + $del = $diff->orig(); + $add = $diff->closing(); + + # Notice that WordLevelDiff returns HTML-escaped output. + # Hence, we will be calling addedLine/deletedLine without HTML-escaping. + + while ( $line = array_shift( $del ) ) { + $aline = array_shift( $add ); + echo '' . $this->deletedLine( $line ) . + $this->addedLine( $aline ) . "\n"; + } + foreach ( $add as $line ) { # If any leftovers + echo '' . $this->emptyLine() . + $this->addedLine( $line ) . "\n"; + } + wfProfileOut( __METHOD__ ); + } +} -- cgit v1.2.2