Subject: Re: [PATCH v2] merge-tree: don't print entries that match "local"

From: John Keeping <[email-masked]>
Date: Sat, 27 Apr 2013 13:55:40 +0100

On Sat, Apr 27, 2013 at 01:35:57PM +0200, René Scharfe wrote:
> Am 07.04.2013 23:07, schrieb John Keeping:
> > The documentation says:
> >
> > 	the output from the command omits entries that match the
> > 	<branch1> tree.
> >
> > But currently "added in branch1" and "removed in branch1" (both while
> > unchanged in branch2) do print output.  Change this so that the
> > behaviour matches the documentation.
> >
> > Signed-off-by: John Keeping <[email-masked]>
> > ---
> >   builtin/merge-tree.c  | 26 +++++++++++++-------------
> >   t/t4300-merge-tree.sh | 10 ----------
> >   2 files changed, 13 insertions(+), 23 deletions(-)
> >
> > diff --git a/builtin/merge-tree.c b/builtin/merge-tree.c
> > index bc912e3..ed25d81 100644
> > --- a/builtin/merge-tree.c
> > +++ b/builtin/merge-tree.c
> > @@ -155,6 +155,11 @@ static int same_entry(struct name_entry *a, struct name_entry *b)
> >   		a->mode == b->mode;
> >   }
> >
> > +static int both_empty(struct name_entry *a, struct name_entry *b)
> > +{
> > +	return !(a->sha1 || b->sha1);
> > +}
> > +
> >   static struct merge_list *create_entry(unsigned stage, unsigned mode, const unsigned char *sha1, const char *path)
> >   {
> >   	struct merge_list *res = xcalloc(1, sizeof(*res));
> > @@ -297,13 +302,10 @@ static void unresolved(const struct traverse_info *info, struct name_entry n[3])
> >   static int threeway_callback(int n, unsigned long mask, unsigned long dirmask, struct name_entry *entry, struct traverse_info *info)
> >   {
> >   	/* Same in both? */
> > -	if (same_entry(entry+1, entry+2)) {
> > -		if (entry[0].sha1) {
> > -			/* Modified identically */
> > -			resolve(info, NULL, entry+1);
> > -			return mask;
> > -		}
> > -		/* "Both added the same" is left unresolved */
> > +	if (same_entry(entry+1, entry+2) || both_empty(entry+0, entry+2)) {
> 
> Shouldn't this zero be a one instead?

Yes, that's a typo.

> > +		/* Modified, added or removed identically */
> > +		resolve(info, NULL, entry+1);
> > +		return mask;
> >   	}
> >
> >   	if (same_entry(entry+0, entry+1)) {
> > @@ -319,12 +321,10 @@ static int threeway_callback(int n, unsigned long mask, unsigned long dirmask, s
> >   		 */
> >   	}
> >
> > -	if (same_entry(entry+0, entry+2)) {
> > -		if (entry[1].sha1 && !S_ISDIR(entry[1].mode)) {
> > -			/* We modified, they did not touch -- take ours */
> > -			resolve(info, NULL, entry+1);
> > -			return mask;
> > -		}
> > +	if (same_entry(entry+0, entry+2) || both_empty(entry+0, entry+2)) {
> 
> Otherwise the both_empty check here can be removed because we'd have 
> already returned above if it was true.
> 
> But do we actually want to resolve the removal of a file on both sides 
> silently?  The added comment above says so, but the commit message 
> doesn't mention it.

I think so.  The rule is that we omit things that match the branch1
tree.  So if it is removed in branch1 and there isn't a conflict with
branch2 then we shouldn't be printing any output.

> > +		/* We added, modified or removed, they did not touch -- take ours */
> > +		resolve(info, NULL, entry+1);
> > +		return mask;
> >   	}
> >
> >   	unresolved(info, entry);
> > diff --git a/t/t4300-merge-tree.sh b/t/t4300-merge-tree.sh
> > index d0b2a45..bd43b3d 100755
> > --- a/t/t4300-merge-tree.sh
> > +++ b/t/t4300-merge-tree.sh
> > @@ -26,8 +26,6 @@ EXPECTED
> >
> >   test_expect_success 'file add !A, B' '
> >   	cat >expected <<\EXPECTED &&
> > -added in local
> > -  our    100644 43d5a8ed6ef6c00ff775008633f95787d088285d ONE
> >   EXPECTED
> >
> >   	git reset --hard initial &&
> > @@ -38,9 +36,6 @@ EXPECTED
> >
> >   test_expect_success 'file add A, B (same)' '
> >   	cat >expected <<\EXPECTED &&
> > -added in both
> > -  our    100644 43d5a8ed6ef6c00ff775008633f95787d088285d ONE
> > -  their  100644 43d5a8ed6ef6c00ff775008633f95787d088285d ONE
> >   EXPECTED
> >
> >   	git reset --hard initial &&
> > @@ -181,9 +176,6 @@ AAA" &&
> >
> >   test_expect_success 'file remove A, !B' '
> >   	cat >expected <<\EXPECTED &&
> > -removed in local
> > -  base   100644 43d5a8ed6ef6c00ff775008633f95787d088285d ONE
> > -  their  100644 43d5a8ed6ef6c00ff775008633f95787d088285d ONE
> >   EXPECTED
> >
> >   	git reset --hard initial &&
> > @@ -283,8 +275,6 @@ test_expect_success 'turn tree to file' '
> >   	test_commit "make-file" "dir" "CCC" &&
> >   	git merge-tree add-tree add-another-tree make-file >actual &&
> >   	cat >expect <<-\EOF &&
> > -	added in local
> > -	  our    100644 ba629238ca89489f2b350e196ca445e09d8bb834 dir/another
> >   	removed in remote
> >   	  base   100644 43d5a8ed6ef6c00ff775008633f95787d088285d dir/path
> >   	  our    100644 43d5a8ed6ef6c00ff775008633f95787d088285d dir/path
> >
>