threads / patch / 43324

patchgitweb: Do not show difftree for merges in "commit" view

Subject: [PATCH] gitweb: Do not show difftree for merges in "commit" view

## tl;dr

3 messages between Dec 15, 2006 and Dec 15, 2006. Diffs are folded; open one to read it.

replies: 2people: 2as markdown or json

Jakub Narebski· Dec 15, 2006, 15:57 UTC · lore

Re: Avoiding uninteresting merges in Cairo

Shawn Pearce wrote:
Show 23 quoted lines
> Jakub Narebski <jnareb@gmail.com> wrote:
>> Carl Worth wrote:
>> 
>>> On Thu, 14 Dec 2006 22:25:30 -0500, Shawn Pearce wrote:
>> 
>>>>  * gitweb made it appear as though a whole lot of Carl's recent
>>>>    work was somehow undone in the merge.
>>> 
>>> That looks like a simple gitweb bug. None of the other tools, (gitk,
>>> git log -p), consider a trivial merge commit like this as having
>>> anything interesting in it worth displaying.
>> 
>> It's not a bug, it is rather lack of feature (or misfeature).
> 
> Its a bug.
> 
> I'm not a gitweb user (meaning I almost never look at something
> in gitweb).  But I'm clearly also not a Git newbie.  ;-)
> 
> I could not fathom why that merge commit was being displayed that
> way in gitweb.  I had to clone the cairo project just so I could
> actually look at the commit with log/show/whatchanged/diff-tree,
> because I couldn't believe what I was seeing from gitweb.

Do you mean "commit" view or "commitdiff" view in gitweb for merges is confusing?

If it is "commit" view, it is fairly easy to remove difftree/whatchanged output below commit message for merges. However while git-show nor git-diff-tree doesn't show diff for merge messages, the diftree output in "commit" view might be taken as 'damages'; git diff --summary always takes summary of diff against first parent.

If it is "commitdiff" view... well, I plan on adding combined diff output to commitdiff, but I need raw (whatchanged) output with the same files which would be shown in git-diff --cc for merges (compact combined diff output). Otherwise I'd have to use combined (-c) output in gitweb, rather than more terse --cc output.

-- 
Jakub Narebski
Shawn Pearce· Dec 15, 2006, 16:03 UTC · re: Jakub Narebski · lore

Re: Avoiding uninteresting merges in Cairo

Jakub Narebski <jnareb@gmail.com> wrote:
> Do you mean "commit" view or "commitdiff" view in gitweb for merges
> is confusing?
The commit view was what was confusing me.
Show 5 quoted lines
> If it is "commit" view, it is fairly easy to remove difftree/whatchanged
> output below commit message for merges. However while git-show nor 
> git-diff-tree doesn't show diff for merge messages, the diftree output
> in "commit" view might be taken as 'damages'; git diff --summary always
> takes summary of diff against first parent.

I can see that, but it depends on what the current branch was when you do the merge. In the cairo case I was looking at yesterday the "damages" from the merge were actually what was already considered to be in the mainline as part of the project due to committer pulling the remote master into his own master before pushing.

Given that the "push; whoops; pull; push" pattern is so common to Git I think it is sort of misleading to show a merge like this; lots of activity may have been pulled in from the central branch during that pull.

iirc git whatchanged for a merge shows only files which cannot be found in any of the parents; these the files which the merge commit itself contributed directly. If that set is empty then the commit just isn't shown by git whatchanged.

Jakub Narebski· Dec 15, 2006, 16:53 UTC · re: Shawn Pearce · lore

Do not show difftree against first parent for merges (commits with more than one parent) in "commit" view, because it usually is misleading. git-show and git-whatchanged doesn't show diff for merges either.

Signed-off-by: Jakub Narebski <jnareb@gmail.com>
---
 gitweb/gitweb.perl |   22 +++++++++++++++-------
 1 files changed, 15 insertions(+), 7 deletions(-)
Show changes to gitweb/gitweb.perl +15 −7
diff --git a/gitweb/gitweb.perl b/gitweb/gitweb.perl
index 040ee71..ebf35a1 100755
--- a/gitweb/gitweb.perl
+++ b/gitweb/gitweb.perl
@@ -3572,14 +3572,19 @@ sub git_commit {
 	my %cd = parse_date($co{'committer_epoch'}, $co{'committer_tz'});
 
 	my $parent = $co{'parent'};
+	my $parents = $co{'parents'};
 	if (!defined $parent) {
 		$parent = "--root";
 	}
-	open my $fd, "-|", git_cmd(), "diff-tree", '-r', "--no-commit-id",
-		@diff_opts, $parent, $hash, "--"
-		or die_error(undef, "Open git-diff-tree failed");
-	my @difftree = map { chomp; $_ } <$fd>;
-	close $fd or die_error(undef, "Reading git-diff-tree failed");
+	my @difftree;
+	if (@$parents <= 1) {
+		# difftree output is not printed for merges
+		open my $fd, "-|", git_cmd(), "diff-tree", '-r', "--no-commit-id",
+			@diff_opts, $parent, $hash, "--"
+				or die_error(undef, "Open git-diff-tree failed");
+		@difftree = map { chomp; $_ } <$fd>;
+		close $fd or die_error(undef, "Reading git-diff-tree failed");
+	}
 
 	# non-textual hash id's can be cached
 	my $expires;
@@ -3641,7 +3646,7 @@ sub git_commit {
 	}
 	print "</td>" .
 	      "</tr>\n";
-	my $parents = $co{'parents'};
+
 	foreach my $par (@$parents) {
 		print "<tr>" .
 		      "<td>parent</td>" .
@@ -3663,7 +3668,10 @@ sub git_commit {
 	git_print_log($co{'comment'});
 	print "</div>\n";
 
-	git_difftree_body(\@difftree, $hash, $parent);
+	if (@$parents <= 1) {
+		# do not output difftree/whatchanged for merges
+		git_difftree_body(\@difftree, $hash, $parent);
+	}
 
 	git_footer_html();
 }

-- 
1.4.4.1

← back to recent threads