[PATCH v1 2/2] merge with untracked file that are the same without failure

[Jonathan <git.jonathan.bressat@xxxxxxxxx>]

In unpack-trees.c in the check_ok_to_remove() function: add a new
statement, if the file has the same content as the merged file, it
can be removed.

test this new behaviour in t7615.

Signed-off-by: Jonathan <git.jonathan.bressat@xxxxxxxxx>
Signed-off-by: COGONI Guillaume <cogoni.guillaume@xxxxxxxxx>
---
 t/t7615-merge-untracked.sh | 8 ++++----
 unpack-trees.c             | 5 ++++-
 2 files changed, 8 insertions(+), 5 deletions(-)

diff --git a/t/t7615-merge-untracked.sh b/t/t7615-merge-untracked.sh
index 053e6b80ee..99f8bae4c0 100755
--- a/t/t7615-merge-untracked.sh
+++ b/t/t7615-merge-untracked.sh
@@ -12,13 +12,13 @@ test_expect_success 'setup' '
 	git checkout -b A
 '
 
-test_expect_success 'fastforward fail when untracked file has the same content' '
+test_expect_success 'fastforward overwrite untracked file that has the same content' '
 	test_when_finished "git branch -D B && git reset --hard init && git clean --force" &&
 	git checkout -b B &&
 	test_commit --no-tag "tracked" file "content" &&
 	git checkout A &&
 	echo content >file &&
-	test_must_fail git merge B
+	git merge B
 '
 
 test_expect_success 'fastforward fail when untracked file has different content' '
@@ -30,14 +30,14 @@ test_expect_success 'fastforward fail when untracked file has different content'
 	test_must_fail git merge B
 '
 
-test_expect_success 'normal merge fail when untracked file has the same content' '
+test_expect_success 'normal merge overwrite untracked file that has the same content' '
 	test_when_finished "git branch -D B && git reset --hard init && git clean --force" &&
 	git checkout -b B &&
 	test_commit --no-tag "tracked" file "content" fileB "content" &&
 	git switch A &&
 	test_commit --no-tag "exA" fileA "content" &&
 	echo content >file &&
-	test_must_fail git merge B
+	git merge B
 '
 
 test_expect_success 'normal merge fail when untracked file has different content' '
diff --git a/unpack-trees.c b/unpack-trees.c
index 360844bda3..61e06c04be 100644
--- a/unpack-trees.c
+++ b/unpack-trees.c
@@ -2257,6 +2257,8 @@ static int check_ok_to_remove(const char *name, int len, int dtype,
 	if (result) {
 		if (result->ce_flags & CE_REMOVE)
 			return 0;
+	} else if (!ie_modified(&o->result, ce, st, 0)) {
+		return 0;
 	}
 
 	return add_rejected_path(o, error_type, name);
@@ -2264,7 +2266,8 @@ static int check_ok_to_remove(const char *name, int len, int dtype,
 
 /*
  * We do not want to remove or overwrite a working tree file that
- * is not tracked, unless it is ignored.
+ * is not tracked, unless it is ignored and unless it has the same
+ * content than the merged file.
  */
 static int verify_absent_1(const struct cache_entry *ce,
 			   enum unpack_trees_error_types error_type,
-- 
2.35.1.7.gc8609858e0.dirty