patch.diff

diff --git i/WebKitTools/Scripts/update-webkit w/WebKitTools/Scripts/update-webkit
index 7602c41..fd1f3c1 100755
--- i/WebKitTools/Scripts/update-webkit
+++ w/WebKitTools/Scripts/update-webkit
@@ -73,7 +73,7 @@ push @svnOptions, '-q' if $quiet;
 # Don't prompt when using svn-1.6 or newer.
 push @svnOptions, qw(--accept postpone) if isSVNVersion16OrNewer();
 
-print "Updating OpenSource\n" unless $quiet;
+print "Updating from WebKit trunk...\n" unless $quiet;
 runSvnUpdate() if $isSVN;
 runGitUpdate() if $isGit;
 
@@ -92,29 +92,127 @@ setupAppleWinEnv() if isAppleWinWebKit();
 
 exit 0;
 
+sub resolveChangeLogs
+{
+    my @conflictedChangeLogs = @_;
+    print "Attempting to automatically resolve conflicted ChangeLogs...\n";
+    my $resolveChangeLogsPath = File::Spec->catfile(dirname($0), "resolve-ChangeLogs");
+    (system($resolveChangeLogsPath, "--no-warnings", @conflictedChangeLogs) == 0)
+        or die "Could not open resolve-ChangeLogs script: $!.\n";
+}
+
 sub runSvnUpdate()
 {
     open UPDATE, "-|", "svn", "update", @svnOptions or die;
     my @conflictedChangeLogs;
+    my @conflictedOtherFiles;
     while (my $line = <UPDATE>) {
         print $line;
-        $line =~ m/^C\s+(.+?)[\r\n]*$/;
-        if ($1) {
-          my $filename = normalizePath($1);
-          push @conflictedChangeLogs, $filename if basename($filename) eq "ChangeLog";
+        if ($line =~ m/^C\s+(.+?)[\r\n]*$/) {
+            my $filename = normalizePath($1);
+            if (basename($filename) eq "ChangeLog") {
+                push @conflictedChangeLogs, $filename;
+            } else {
+                push @conflictedOtherFiles, $filename;
+            }
         }
     }
     close UPDATE or die;
 
-    if (@conflictedChangeLogs) {
-        print "Attempting to merge conflicted ChangeLogs.\n";
-        my $resolveChangeLogsPath = File::Spec->catfile(dirname($0), "resolve-ChangeLogs");
-        (system($resolveChangeLogsPath, "--no-warnings", @conflictedChangeLogs) == 0)
-            or die "Could not open resolve-ChangeLogs script: $!.\n";
+    resolveChangeLogs(@conflictedChangeLogs) if @conflictedChangeLogs;
+
+    # TODO: Deal with changelogs that could not be resolved, or other conflicting files 
+}
+
+sub runGitRebase
+{
+    my ($ref, $continue) = @_;
+
+    my @conflictedChangeLogs;
+    my @conflictedOtherFiles;
+
+    open REBASE, "-|", "git", "rebase", ($continue ? "--continue" : $ref ) or die;
+    while (my $line = <REBASE>) {
+        print $line;
+        if ($line =~ m/: Merge conflict in (.+?)$/) {
+            my $filename = normalizePath($1);
+            print "file: $filename\n";
+            if (basename($filename) eq "ChangeLog") {
+                push @conflictedChangeLogs, $filename;
+            } else {
+                push @conflictedOtherFiles, $filename;
+            }
+        }
     }
+    close REBASE;
+
+    return (\@conflictedChangeLogs, \@conflictedOtherFiles);
 }
 
 sub runGitUpdate()
 {
-    system("git", "svn", "rebase") == 0 or die;
+    my $unstaged = `git update-index --ignore-submodules --refresh`;
+    die "You have unstaged changes, please stash before updating\n" if $?;
+
+    my $staged = `git diff-index --cached --name-status -r --ignore-submodules HEAD --`;
+    die("You have staged changes, please stash before updating\n") if $staged;
+
+    # Resolve the git-svn ref name
+    my @refspec = split(/:/, `git config --get svn-remote.svn.fetch`);
+    my $svn_ref = @refspec > 1 ? $refspec[1] : undef;
+    chomp($svn_ref) if $svn_ref;
+
+    my $mirror_ref = undef;
+
+    # Check the git config for a possible mirror remote we can use
+    my $remotes = `git config --get-regexp "^remote\..+\.url"`;
+    if ($remotes =~ /^remote\.(.*?)\.url .*?\/webkit\.git$/mi) {
+        my $mirror = $1;
+        @refspec = split(/:/, `git config --get remote.$mirror.fetch`);
+        if (@refspec > 1) {
+            $mirror_ref = $refspec[1];
+            chomp($mirror_ref);
+            $mirror_ref =~ s/\*$/master/;
+
+            # Fetch latest changes from the mirror first, since it's faster
+            system("git", "fetch", $mirror) == 0 or die;
+
+            if ($svn_ref) {
+                # Fast forward the git-svn ref if the mirror is more recent
+                my $cherry = `git cherry $svn_ref $mirror_ref`;
+
+                if ($cherry =~ /^[+|-]/) {
+                    my $latest_mirror_sha = `git rev-parse $mirror_ref`;
+                    chomp($latest_mirror_sha);
+                    system("git", "update-ref", $svn_ref, $latest_mirror_sha) == 0 or die;
+                }
+            }
+        }
+    }
+
+    if ($svn_ref) {
+        # Fetch latest changes from SVN (the mirror may be a few minutes old)
+        system("git", "svn", "fetch");
+    }
+
+    my $rebase_ref = $svn_ref ? $svn_ref : $mirror_ref;
+    if (!$rebase_ref) {
+        die "Could not find a suitable remote branch to rebase against.\n";
+    }
+
+    # Do rebase
+    my ($conflictedChangeLogs, $conflictedOtherFiles) = runGitRebase($rebase_ref);
+    if (@$conflictedChangeLogs) {
+        resolveChangeLogs(@$conflictedChangeLogs);
+        ($conflictedChangeLogs, $conflictedOtherFiles) = runGitRebase($rebase_ref, 1);
+    }
+
+    # Deal with changelogs that failed to resolve, or other conflicting files
+    if (@$conflictedChangeLogs or @$conflictedOtherFiles) {
+        print "The following files need to be manually resolved:\n";
+        foreach my $file (@$conflictedChangeLogs, @$conflictedOtherFiles) {
+            print "\t$file\n";
+        }
+        print "\n";
+    }
 }