revision.c: --full-history fix.
With history simplification, we still show merges that are required
to make the history _complete_, i.e. say that you had:
a
|
b
/ \
c d
| |
and neither "a" nor "b" actually changed the file, but both "c" and "d"
did: in this case we have to leave "b" around just because otherwise there
would be no way to show the _relationship_, even if "b" itself doesn't
actually change the tree in any way what-so-ever.
It would make sense to make that further simplification if the
"--parents" flag wasn't present. In that case the user is
literally asking for a list of commits and is not interested in
the relationship between them.
This patch also fixes a real bug. Without this patch, the
"--parents --full-history" combination (which you'd get if you
do something like
gitk --full-history Makefile
or similar) will actually _drop_ merges where all children are identical.
That's wrong in the --full-history case, because it means that the graph
ends up missing lots of entries.
In the process, this also should make
git-rev-list --full-history Makefile
give just the _true_ list of all commits that changed Makefile (and
properly ignore merges that were identical in one parent), because now
we're not asking for "--parent", so we don't need the unnecessary merge
commits to keep the history together.
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
diff --git a/revision.c b/revision.c
index b963f2a..1cf6276 100644
--- a/revision.c
+++ b/revision.c
@@ -280,7 +280,7 @@
static void try_to_simplify_commit(struct rev_info *revs, struct commit *commit)
{
struct commit_list **pp, *parent;
- int tree_changed = 0;
+ int tree_changed = 0, tree_same = 0;
if (!commit->tree)
return;
@@ -298,6 +298,7 @@
parse_commit(p);
switch (rev_compare_tree(revs, p->tree, commit->tree)) {
case REV_TREE_SAME:
+ tree_same = 1;
if (!revs->simplify_history || (p->object.flags & UNINTERESTING)) {
/* Even if a merge with an uninteresting
* side branch brought the entire change
@@ -334,7 +335,7 @@
}
die("bad tree compare for commit %s", sha1_to_hex(commit->object.sha1));
}
- if (tree_changed)
+ if (tree_changed && !tree_same)
commit->object.flags |= TREECHANGE;
}
@@ -896,6 +897,8 @@
struct commit *p = *pp;
if (!revs->limited)
add_parents_to_list(revs, p, &revs->commits);
+ if (p->parents && p->parents->next)
+ return 0;
if (p->object.flags & (TREECHANGE | UNINTERESTING))
return 0;
if (!p->parents)
@@ -988,8 +991,15 @@
commit->parents && commit->parents->next)
continue;
if (revs->prune_fn && revs->dense) {
- if (!(commit->object.flags & TREECHANGE))
- continue;
+ /* Commit without changes? */
+ if (!(commit->object.flags & TREECHANGE)) {
+ /* drop merges unless we want parenthood */
+ if (!revs->parents)
+ continue;
+ /* non-merge - always ignore it */
+ if (commit->parents && !commit->parents->next)
+ continue;
+ }
if (revs->parents)
rewrite_parents(revs, commit);
}
