/includes/diff/DairikiDiff.php
PHP | 1476 lines | 834 code | 151 blank | 491 comment | 160 complexity | a0c49071bffa609a2ae66b828448ce1f MD5 | raw file
Possible License(s): GPL-2.0, Apache-2.0, LGPL-3.0
- <?php
- /**
- * A PHP diff engine for phpwiki. (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.
- *
- * @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 );
- }
- /**
- * @return int
- */
- function norig() {
- return $this->orig ? sizeof( $this->orig ) : 0;
- }
- /**
- * @return int
- */
- 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;
- }
- /**
- * @return _DiffOp_Copy
- */
- 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;
- }
- /**
- * @return _DiffOp_Add
- */
- 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;
- }
- /**
- * @return _DiffOp_Delete
- */
- 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;
- }
- /**
- * @return _DiffOp_Change
- */
- 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;
- /**
- * @param $from_lines
- * @param $to_lines
- * @return array
- */
- 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;
- }
- /**
- * @param $from_lines
- * @param $to_lines
- */
- 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
- * @param $line string
- * @return string
- */
- 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.
- * @param $xoff
- * @param $xlim
- * @param $yoff
- * @param $ylim
- * @param $nchunks
- * @return array
- */
- 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 );
- }
- /**
- * @param $ypos
- * @return int
- */
- 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.
- * @param $xoff
- * @param $xlim
- * @param $yoff
- * @param $ylim
- */
- 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.
- * @param $from_lines
- * @param $to_lines
- */
- 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;
- }
- /**
- * @param $xbeg
- * @param $xlen
- * @param $ybeg
- * @param $ylen
- * @param $edits
- */
- 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();
- }
- /**
- * @return string
- */
- function _end_diff() {
- $val = ob_get_contents();
- ob_end_clean();
- return $val;
- }
- /**
- * @param $xbeg
- * @param $xlen
- * @param $ybeg
- * @param $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;
- }
- function _start_block( $header ) {
- echo $header . "\n";
- }
- function _end_block() {
- }
- /**
- * @param $lines
- * @param $prefix string
- */
- function _lines( $lines, $prefix = ' ' ) {
- foreach ( $lines as $line ) {
- echo "$prefix $line\n";
- }
- }
- /**
- * @param $lines
- */
- function _context( $lines ) {
- $this->_lines( $lines );
- }
- /**
- * @param $lines
- */
- function _added( $lines ) {
- $this->_lines( $lines, '>' );
- }
- /**
- * @param $lines
- */
- function _deleted( $lines ) {
- $this->_lines( $lines, '<' );
- }
- /**
- * @param $orig
- * @param $closing
- */
- 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;
- /**
- * @param $lines
- */
- function _added( $lines ) {
- $this->_lines( $lines, '+' );
- }
- /**
- * @param $lines
- */
- function _deleted( $lines ) {
- $this->_lines( $lines, '-' );
- }
- /**
- * @param $orig
- * @param $closing
- */
- function _changed( $orig, $closing ) {
- $this->_deleted( $orig );
- $this->_added( $closing );
- }
- /**
- * @param $xbeg
- * @param $xlen
- * @param $ybeg
- * @param $ylen
- * @return string
- */
- 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 {
- /**
- * @param $diff
- * @return array
- */
- 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 = '';
- }
- /**
- * @param $new_tag
- */
- function _flushGroup( $new_tag ) {
- if ( $this->_group !== '' ) {
- if ( $this->_tag == 'ins' ) {
- $this->_line .= '<ins class="diffchange diffchange-inline">' .
- htmlspecialchars( $this->_group ) . '</ins>';
- } elseif ( $this->_tag == 'del' ) {
- $this->_line .= '<del class="diffchange diffchange-inline">' .
- htmlspecialchars( $this->_group ) . '</del>';
- } else {
- $this->_line .= htmlspecialchars( $this->_group );
- }
- }
- $this->_group = '';
- $this->_tag = $new_tag;
- }
- /**
- * @param $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 = '';
- }
- /**
- * @param $words
- * @param $tag string
- */
- 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;
- }
- }
- /**
- * @return array
- */
- function getLines() {
- $this->_flushLine( '~done' );
- return $this->_lines;
- }
- }
- /**
- * @todo document
- * @private
- * @ingroup DifferenceEngine
- */
- class WordLevelDiff extends MappedDiff {
- const MAX_LINE_LENGTH = 10000;
- /**
- * @param $orig_lines
- * @param $closing_lines
- */
- 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__ );
- }
- /**
- * @param $lines
- * @return array
- */
- 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 );
- }
- /**
- * @return array
- */
- 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;
- }
- /**
- * @return array
- */
- 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;
- }
- /**
- * @static
- * @param $msg
- * @return mixed
- */
- public static function escapeWhiteSpace( $msg ) {
- $msg = preg_replace( '/^ /m', '  ', $msg );
- $msg = preg_replace( '/ $/m', '  ', $msg );
- $msg = preg_replace( '/ /', '  ', $msg );
- return $msg;
- }
- /**
- * @param $xbeg
- * @param $xlen
- * @param $ybeg
- * @param $ylen
- * @return string
- */
- function _block_header( $xbeg, $xlen, $ybeg, $ylen ) {
- $r = '<tr><td colspan="2" class="diff-lineno"><!--LINE ' . $xbeg . "--></td>\n" .
- '<td colspan="2" class="diff-lineno"><!--LINE ' . $ybeg . "--></td></tr>\n";
- return $r;
- }
- /**
- * @param $header
- */
- function _start_block( $header ) {
- echo $header;
- }
- function _end_block() {
- }
- function _lines( $lines, $prefix = ' ', $color = 'white' ) {
- }
- /**
- * HTML-escape parameter before calling this
- * @param $line
- * @return string
- */
- function addedLine( $line ) {
- return $this->wrapLine( '+', 'diff-addedline', $line );
- }
- /**
- * HTML-escape parameter before calling this
- * @param $line
- * @return string
- */
- function deletedLine( $line ) {
- return $this->wrapLine( '−', 'diff-deletedline', $line );
- }
- /**
- * HTML-escape parameter before calling this
- * @param $line
- * @return string
- */
- function contextLine( $line ) {
- return $this->wrapLine( ' ', 'diff-context', $line );
- }
- /**
- * @param $marker
- * @param $class
- * @param $line
- * @return string
- */
- private function wrapLine( $marker, $class, $line ) {
- if ( $line !== '' ) {
- // The <div> wrapper is needed for 'overflow: auto' style to scroll properly
- $line = Xml::tags( 'div', null, $this->escapeWhiteSpace( $line ) );
- }
- return "<td class='diff-marker'>$marker</td><td class='$class'>$line</td>";
- }
- /**
- * @return string
- */
- function emptyLine() {
- return '<td colspan="2"> </td>';
- }
- /**
- * @param $lines array
- */
- function _added( $lines ) {
- foreach ( $lines as $line ) {
- echo '<tr>' . $this->emptyLine() .
- $this->addedLine( '<ins class="diffchange">' .
- htmlspecialchars( $line ) . '</ins>' ) . "</tr>\n";
- }
- }
- /**
- * @param $lines
- */
- function _deleted( $lines ) {
- foreach ( $lines as $line ) {
- echo '<tr>' . $this->deletedLine( '<del class="diffchange">' .
- htmlspecialchars( $line ) . '</del>' ) .
- $this->emptyLine() . "</tr>\n";
- }
- }
- /**
- * @param $lines
- */
- function _context( $lines ) {
- foreach ( $lines as $line ) {
- echo '<tr>' .
- $this->contextLine( htmlspecialchars( $line ) ) .
- $this->contextLine( htmlspecialchars( $line ) ) . "</tr>\n";
- }
- }
- /**
- * @param $orig
- * @param $closing
- */
- 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 '<tr>' . $this->deletedLine( $line ) .
- $this->addedLine( $aline ) . "</tr>\n";
- }
- foreach ( $add as $line ) { # If any leftovers
- echo '<tr>' . $this->emptyLine() .
- $this->addedLine( $line ) . "</tr>\n";
- }
- wfProfileOut( __METHOD__ );
- }
- }