After a large merge between project branches in CVS we often end up with a bunch of fairly nasty conflicts. We have found that the best way to deal with them is to open two diff windows so that the differences between the common ancestor and the current target are shown in one view, and the differences between the current target and the merged result are shown in another.

This tool is designed so that it can be set up as a desktop shortcut that the merge result file can be dropped onto. It will then open the two diff views.

use warnings; use strict; use Win32::Process; use File::Find; use File::Path; use Tk; my $cvs = '"C:\Program Files\GNU\WinCvs 1.3\CVSNT\cvs"'; my $diffTool; my $confictFile; my $listOnly = 0; while ($_ = shift) { ShowHelp (-3, "Too many parameters provided.\n\n") if defined $con +fictFile; $confictFile = $_ if defined $diffTool; $diffTool = $_ if ! defined $diffTool; } ShowHelp () if ! $diffTool; ErrorBox ("Missing Conflict File", "Can't find $confictFile\n\n") if ! + -e $confictFile; (my $path = $confictFile) =~ s/^(.*)[\/\\](.*?)$/$1/; my $fileName = $2; find (\&setHeadFile, ($path)); my $headFile; # Set in setHeadFile @ARGV = ($confictFile); while (<>) { next if ! />>>>>>>\s+((?:\d+\.){2})/; my $commonRev = substr $1, 0, -1 + length $1; my $commonRevSrc = `$cvs update -P -p -r $commonRev $confictFile`; ErrorBox ("cvs failed", $commonRevSrc) if $?; my $tempFileName = "${confictFile}.$commonRev"; open tempFile, ">", $tempFileName; print tempFile $commonRevSrc; close tempFile; my $proc2; Win32::Process::Create ( $proc2, "$diffTool", "\"$diffTool\" $headFile $confictFile", 0, NORMAL_PRIORITY_CLASS, "." ) || ErrorBox ("Create failed", Win32::FormatMessage (Win32::GetLa +stError ())); my $proc1; Win32::Process::Create ( $proc1, "$diffTool", "\"$diffTool\" $tempFileName $headFile", 0, NORMAL_PRIORITY_CLASS, "." ) || ErrorBox ("Create failed", Win32::FormatMessage (Win32::GetLa +stError ())); exit (0); } ErrorBox ("No conflicts", "No conficts found in $confictFile"); sub ShowHelp { my $exitValue = 0; $exitValue = shift if defined $_[0] and $_[0] =~ /^[-+]?\d+$/; print $_ while $_ = shift; print "ConflictCompare opens two diff tool apps to compare the HEAD me +rged result\n"; print "against the common ancestor and the branch version that was mer +ged.\n"; print "\n"; print "Usage:\n\n"; print "ConflictCompare [-n] <tool cmd line> <.# conflict file>\n"; print "\n"; print " -n: show progress information.\n"; print "\n"; exit ($exitValue || -1); } sub ErrorBox { my $main = MainWindow->new (); my $title = shift; my $message = shift; $main->withdraw (); $main->messageBox(-icon => 'error', -message => $message, -title => $t +itle, -type => 'Ok'); exit (-2); } sub setHeadFile { return if $File::Find::name =~ /^\.\.?/; return if $File::Find::name !~ /$fileName(?:\.\d+)+/; return if $headFile and -M $headFile >= -M $File::Find::name; $headFile = $File::Find::name; }

Perl is Huffman encoded by design.

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Re: Open diff windows looking at CVS file merge conflicts
by cLive ;-) (Prior) on Sep 02, 2005 at 19:40 UTC
    I think you'll find this a lot less work for comparing - if you can get off the windows box :)

      A 3 way compare is not the immediate problem. There are very good tools available for that on pretty much any common platform (Araxis Merge on Windows for example). The larger part of the problem is that the three files required for the compare are not all immediately available. This script allows a single file to be dropped onto a short cut, then determines the other files to be compared, retreives the missing file from CVS, and opens the three files - currently using two instances of a diff tool that compares two files, but easily altered to open the three files with a three way diff tool.


      Perl is Huffman encoded by design.