read-tree: make three-way merge sparse-aware
Enable use of 'merged_sparse_dir' in 'threeway_merge'. As with two-way
merge, the contents of each conflicted sparse directory are merged without
referencing the index, avoiding sparse index expansion.
As with two-way merge, the 't/t1092-sparse-checkout-compatibility.sh' test
'read-tree --merge with edit/edit conflicts in sparse directories' confirms
that three-way merges with edit/edit changes (both with and without
conflicts) inside a sparse directory result in the correct index state or
error message. To ensure the index is not unnecessarily expanded, add
three-way merge cases to 'sparse index is not expanded: read-tree'.
Signed-off-by: Victoria Dye <vdye@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/unpack-trees.c b/unpack-trees.c
index 0c2a678..b876cac 100644
--- a/unpack-trees.c
+++ b/unpack-trees.c
@@ -2643,16 +2643,24 @@ int threeway_merge(const struct cache_entry * const *stages,
*/
/* #14, #14ALT, #2ALT */
if (remote && !df_conflict_head && head_match && !remote_match) {
- if (index && !same(index, remote) && !same(index, head))
- return reject_merge(index, o);
+ if (index && !same(index, remote) && !same(index, head)) {
+ if (S_ISSPARSEDIR(index->ce_mode))
+ return merged_sparse_dir(stages, 4, o);
+ else
+ return reject_merge(index, o);
+ }
return merged_entry(remote, index, o);
}
/*
* If we have an entry in the index cache, then we want to
* make sure that it matches head.
*/
- if (index && !same(index, head))
- return reject_merge(index, o);
+ if (index && !same(index, head)) {
+ if (S_ISSPARSEDIR(index->ce_mode))
+ return merged_sparse_dir(stages, 4, o);
+ else
+ return reject_merge(index, o);
+ }
if (head) {
/* #5ALT, #15 */
@@ -2714,11 +2722,21 @@ int threeway_merge(const struct cache_entry * const *stages,
}
- /* Below are "no merge" cases, which require that the index be
- * up-to-date to avoid the files getting overwritten with
- * conflict resolution files.
- */
+ /* Handle "no merge" cases (see t/t1000-read-tree-m-3way.sh) */
if (index) {
+ /*
+ * If we've reached the "no merge" cases and we're merging
+ * a sparse directory, we may have an "edit/edit" conflict that
+ * can be resolved by individually merging directory contents.
+ */
+ if (S_ISSPARSEDIR(index->ce_mode))
+ return merged_sparse_dir(stages, 4, o);
+
+ /*
+ * If we're not merging a sparse directory, ensure the index is
+ * up-to-date to avoid files getting overwritten with conflict
+ * resolution files
+ */
if (verify_uptodate(index, o))
return -1;
}
