Clean up and simplify rev_compare_tree()
This simplifies the logic of rev_compare_tree() by removing a special
case.
It does so by turning the special case of finding a diff to be "all new
files" into a more generic case of "all new" vs "all removed" vs "mixed
changes", so now the code is actually more powerful and more generic, and
the added symmetry actually makes it simpler too.
This makes no changes to any existing behavior, but apart from the
simplification it does make it possible to some day care about whether all
changes were just deletions if we want to. Which we may well want to for
merge handling.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/revision.c b/revision.c
index 18b7ebb..bf58448 100644
--- a/revision.c
+++ b/revision.c
@@ -256,10 +256,12 @@
/*
* The goal is to get REV_TREE_NEW as the result only if the
- * diff consists of all '+' (and no other changes), and
- * REV_TREE_DIFFERENT otherwise (of course if the trees are
- * the same we want REV_TREE_SAME). That means that once we
- * get to REV_TREE_DIFFERENT, we do not have to look any further.
+ * diff consists of all '+' (and no other changes), REV_TREE_OLD
+ * if the whole diff is removal of old data, and otherwise
+ * REV_TREE_DIFFERENT (of course if the trees are the same we
+ * want REV_TREE_SAME).
+ * That means that once we get to REV_TREE_DIFFERENT, we do not
+ * have to look any further.
*/
static int tree_difference = REV_TREE_SAME;
@@ -268,22 +270,9 @@
const unsigned char *sha1,
const char *fullpath)
{
- int diff = REV_TREE_DIFFERENT;
+ int diff = addremove == '+' ? REV_TREE_NEW : REV_TREE_OLD;
- /*
- * Is it an add of a new file? It means that the old tree
- * didn't have it at all, so we will turn "REV_TREE_SAME" ->
- * "REV_TREE_NEW", but leave any "REV_TREE_DIFFERENT" alone
- * (and if it already was "REV_TREE_NEW", we'll keep it
- * "REV_TREE_NEW" of course).
- */
- if (addremove == '+') {
- diff = tree_difference;
- if (diff != REV_TREE_SAME)
- return;
- diff = REV_TREE_NEW;
- }
- tree_difference = diff;
+ tree_difference |= diff;
if (tree_difference == REV_TREE_DIFFERENT)
DIFF_OPT_SET(options, HAS_CHANGES);
}
@@ -305,6 +294,8 @@
if (!t1)
return REV_TREE_NEW;
+ if (!t2)
+ return REV_TREE_OLD;
if (revs->simplify_by_decoration) {
/*
@@ -323,8 +314,7 @@
if (!revs->prune_data)
return REV_TREE_SAME;
}
- if (!t2)
- return REV_TREE_DIFFERENT;
+
tree_difference = REV_TREE_SAME;
DIFF_OPT_CLR(&revs->pruning, HAS_CHANGES);
if (diff_tree_sha1(t1->object.sha1, t2->object.sha1, "",
@@ -429,6 +419,7 @@
p->parents = NULL;
}
/* fallthrough */
+ case REV_TREE_OLD:
case REV_TREE_DIFFERENT:
tree_changed = 1;
pp = &parent->next;
