[PATCHv2 4/5] unpack-trees: oneway_merge to update submodules

When there is a one way merge, each submodule needs to be one way merged
as well, if we're asked to recurse into submodules.

In case of a submodule, check if it is up-to-date, otherwise set the
flag CE_UPDATE, which will trigger an update of it in the phase updating
the tree later.

Signed-off-by: Stefan Beller <redacted>
---
 unpack-trees.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/unpack-trees.c b/unpack-trees.c
index bf8b602901..ac59524a7f 100644
--- a/unpack-trees.c
+++ b/unpack-trees.c

@@ -2139,6 +2139,9 @@ int oneway_merge(const struct cache_entry * const *src,
 			    ie_match_stat(o->src_index, old, &st, CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE))
 				update |= CE_UPDATE;
 		}
+		if (S_ISGITLINK(old->ce_mode) && should_update_submodules() &&
+		    !verify_uptodate(old, o))
+			update |= CE_UPDATE;
 		add_entry(o, old, update, 0);
 		return 0;
 	}

-- 
2.15.1.620.gb9897f4670-goog