PHP Class Horde_Text_Diff_Engine_Native, horde

This class is implemented using native PHP code. 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 (and a bit of code) are taken from analyze.c, of GNU diffutils-2.7, which can be found at: ftp://gnudist.gnu.org/pub/gnu/diffutils/diffutils-2.7.tar.gz Some ideas (subdivision by NCHUNKS > 2, and some optimizations) are from Geoffrey T. Dairiki . The original PHP version of this code was written by him, and is used/adapted with his permission. Copyright 2004-2016 Horde LLC (http://www.horde.org/) See the enclosed file COPYING for license information (LGPL). If you did not receive this file, see http://www.horde.org/licenses/lgpl21.

Author: Geoffrey T. Dairiki ([email protected])

Mostra file Open project: horde/horde Class Usage Examples

Public Methods

Method	Description
diff ( $from_lines, $to_lines )

Protected Methods

Method	Description
_compareseq ( $xoff, $xlim, $yoff, $ylim )	Finds LCS of two sequences.
_diag ( $xoff, $xlim, $yoff, $ylim, $nchunks )	Divides the Largest Common Subsequence (LCS) of the sequences (XOFF, XLIM) and (YOFF, YLIM) into NCHUNKS approximately equally sized segments.
_lcsPos ( $ypos )
_shiftBoundaries ( $lines, &$changed, $other_changed )	Adjusts inserts/deletes of identical lines to join changes as much as possible.

Method Details

_compareseq() protected method

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.

protected _compareseq ( $xoff, $xlim, $yoff, $ylim )

_diag() protected method

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 public 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.

protected _diag ( $xoff, $xlim, $yoff, $ylim, $nchunks )

_lcsPos() protected method

protected _lcsPos ( $ypos )

_shiftBoundaries() protected method

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).

protected _shiftBoundaries ( $lines, &$changed, $other_changed )

diff() public method

public diff ( $from_lines, $to_lines )