merge-recursive: prepare for `merge_submodule()` to report errors

The `merge_submodule()` function returns an integer that indicates
whether the merge was clean (returning 1) or unclean (returning 0).

Like the version in `merge-ort.c`, the version in `merge-recursive.c`
does not report any errors (such as repository corruption) by returning
-1 as of time of writing, even if the callers in `merge-ort.c` are
prepared for exactly such errors.

However, we want to teach (both variants of) the `merge_submodule()`
function that trick: to report errors by returning -1. Therefore,
prepare the caller in `merge-recursive.c` to handle that scenario.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Acked-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/merge-recursive.c b/merge-recursive.c
index 32e9d6665debefd667324abd18f2ba0e9289f2d6..f3132a9ecaeb3150a4eb41f3fb920d9a70c04a0f 100644 (file)
--- a/merge-recursive.c
+++ b/merge-recursive.c
@@ -1426,13 +1426,14 @@ static int merge_mode_and_contents(struct merge_options *opt,
                        /* FIXME: bug, what if modes didn't match? */
                        result->clean = (merge_status == 0);
                } else if (S_ISGITLINK(a->mode)) {
-                       result->clean = merge_submodule(opt, &result->blob.oid,
-                                                       o->path,
-                                                       &o->oid,
-                                                       &a->oid,
-                                                       &b->oid);
-                       if (result->clean < 0)
+                       int clean = merge_submodule(opt, &result->blob.oid,
+                                                   o->path,
+                                                   &o->oid,
+                                                   &a->oid,
+                                                   &b->oid);
+                       if (clean < 0)
                                return -1;
+                       result->clean = clean;
                } else if (S_ISLNK(a->mode)) {
                        switch (opt->recursive_variant) {
                        case MERGE_VARIANT_NORMAL: