In later patches we introduce the options and flag for commands
that modify the working directory, e.g. git-checkout.
This piece of code will answer the question:
"Is it safe to change the submodule to this new state?"
e.g. is it overwriting untracked files or are there local
changes that would be overwritten?
Signed-off-by: Stefan Beller <sbel...@google.com>
---
submodule.c | 22 ++++++++++++++++++++++
submodule.h | 2 ++
2 files changed, 24 insertions(+)
diff --git a/submodule.c b/submodule.c
index 2773151..2149ef7 100644
--- a/submodule.c
+++ b/submodule.c
@@ -1201,6 +1201,28 @@ int ok_to_remove_submodule(const char *path)
return ok_to_remove;
}
+int is_submodule_checkout_safe(const char *path, const struct object_id *oid)
+{
+ struct child_process cp = CHILD_PROCESS_INIT;
+
+ if (!is_submodule_populated(path))
+ /* The submodule is not populated, it's safe to check it out */
+ /*
+ * TODO: When git learns to re-populate submodules, a check
must be
+ * added here to assert that no local files will be overwritten.
+ */
+ return 1;
+
+ argv_array_pushl(&cp.args, "read-tree", "-n", "-m", "HEAD",
+ sha1_to_hex(oid->hash), NULL);
+
+ prepare_submodule_repo_env(&cp.env_array);
+ cp.git_cmd = 1;
+ cp.no_stdin = 1;
+ cp.dir = path;
+ return run_command(&cp) == 0;
+}
+
static int find_first_merges(struct object_array *result, const char *path,
struct commit *a, struct commit *b)
{
diff --git a/submodule.h b/submodule.h
index f01f87c..a7fa634 100644
--- a/submodule.h
+++ b/submodule.h
@@ -74,6 +74,8 @@ extern unsigned is_submodule_modified(const char *path, int
ignore_untracked);
extern int is_submodule_populated(const char *path);
extern int submodule_uses_gitfile(const char *path);
extern int ok_to_remove_submodule(const char *path);
+extern int is_submodule_checkout_safe(const char *path,
+ const struct object_id *oid);
extern int merge_submodule(unsigned char result[20], const char *path,
const unsigned char base[20],
const unsigned char a[20],
--
2.10.1.469.g00a8914
