thodg/libgit2

diff --git a/include/git2/oid.h b/include/git2/oid.h
index d2f3f4a..862f4b2 100644
--- a/include/git2/oid.h
+++ b/include/git2/oid.h
@@ -51,7 +51,7 @@ GIT_EXTERN(int) git_oid_fromstr(git_oid *out, const char *str);
  *
  * @param out oid structure the result is written into.
  * @param str input hex string; must be at least 4 characters
- *      long and null-terminated. 
+ *      long and null-terminated.
  * @return 0 or an error code
  */
 GIT_EXTERN(int) git_oid_fromstrp(git_oid *out, const char *str);
diff --git a/include/git2/status.h b/include/git2/status.h
index fa62820..38b6fa5 100644
--- a/include/git2/status.h
+++ b/include/git2/status.h
@@ -133,7 +133,8 @@ typedef enum {
  *
  * Calling `git_status_foreach()` is like calling the extended version
  * with: GIT_STATUS_OPT_INCLUDE_IGNORED, GIT_STATUS_OPT_INCLUDE_UNTRACKED,
- * and GIT_STATUS_OPT_RECURSE_UNTRACKED_DIRS.
+ * and GIT_STATUS_OPT_RECURSE_UNTRACKED_DIRS.  Those options are bundled
+ * together as `GIT_STATUS_OPT_DEFAULTS` if you want them as a baseline.
  */
 typedef enum {
 	GIT_STATUS_OPT_INCLUDE_UNTRACKED      = (1u << 0),
@@ -145,6 +146,11 @@ typedef enum {
 	GIT_STATUS_OPT_RECURSE_IGNORED_DIRS   = (1u << 6),
 } git_status_opt_t;
 
+#define GIT_STATUS_OPT_DEFAULTS \
+	(GIT_STATUS_OPT_INCLUDE_IGNORED | \
+	GIT_STATUS_OPT_INCLUDE_UNTRACKED | \
+	GIT_STATUS_OPT_RECURSE_UNTRACKED_DIRS)
+
 /**
  * Options to control how `git_status_foreach_ext()` will issue callbacks.
  *
diff --git a/src/diff.c b/src/diff.c
index 11ffc48..61fd18d 100644
--- a/src/diff.c
+++ b/src/diff.c
@@ -73,6 +73,10 @@ static int diff_delta__from_one(
 		DIFF_FLAG_ISNT_SET(diff, GIT_DIFF_INCLUDE_UNTRACKED))
 		return 0;
 
+	if (entry->mode == GIT_FILEMODE_COMMIT &&
+		DIFF_FLAG_IS_SET(diff, GIT_DIFF_IGNORE_SUBMODULES))
+		return 0;
+
 	if (!git_pathspec_match_path(
 			&diff->pathspec, entry->path,
 			DIFF_FLAG_IS_SET(diff, GIT_DIFF_DISABLE_PATHSPEC_MATCH),
@@ -131,6 +135,11 @@ static int diff_delta__from_two(
 		DIFF_FLAG_ISNT_SET(diff, GIT_DIFF_INCLUDE_UNMODIFIED))
 		return 0;
 
+	if (old_entry->mode == GIT_FILEMODE_COMMIT &&
+		new_entry->mode == GIT_FILEMODE_COMMIT &&
+		DIFF_FLAG_IS_SET(diff, GIT_DIFF_IGNORE_SUBMODULES))
+		return 0;
+
 	if (DIFF_FLAG_IS_SET(diff, GIT_DIFF_REVERSE)) {
 		uint32_t temp_mode = old_mode;
 		const git_index_entry *temp_entry = old_entry;
@@ -548,6 +557,11 @@ static int maybe_modified(
 		}
 	}
 
+	/* if mode is GITLINK and submodules are ignored, then skip */
+	else if (S_ISGITLINK(nmode) &&
+			 DIFF_FLAG_IS_SET(diff, GIT_DIFF_IGNORE_SUBMODULES))
+		status = GIT_DELTA_UNMODIFIED;
+
 	/* if we got here and decided that the files are modified, but we
 	 * haven't calculated the OID of the new item, then calculate it now
 	 */
diff --git a/src/status.c b/src/status.c
index 7f84235..ac6b437 100644
--- a/src/status.c
+++ b/src/status.c
@@ -80,22 +80,37 @@ static unsigned int workdir_delta2status(git_delta_t workdir_status)
 typedef struct {
 	git_status_cb cb;
 	void *payload;
+	const git_status_options *opts;
 } status_user_callback;
 
 static int status_invoke_cb(
-	git_diff_delta *i2h, git_diff_delta *w2i, void *payload)
+	git_diff_delta *h2i, git_diff_delta *i2w, void *payload)
 {
 	status_user_callback *usercb = payload;
 	const char *path = NULL;
 	unsigned int status = 0;
 
-	if (w2i) {
-		path = w2i->old_file.path;
-		status |= workdir_delta2status(w2i->status);
+	if (i2w) {
+		path = i2w->old_file.path;
+		status |= workdir_delta2status(i2w->status);
 	}
-	if (i2h) {
-		path = i2h->old_file.path;
-		status |= index_delta2status(i2h->status);
+	if (h2i) {
+		path = h2i->old_file.path;
+		status |= index_delta2status(h2i->status);
+	}
+
+	/* if excluding submodules and this is a submodule everywhere */
+	if (usercb->opts &&
+		(usercb->opts->flags & GIT_STATUS_OPT_EXCLUDE_SUBMODULES) != 0)
+	{
+		bool in_tree  = (h2i && h2i->status != GIT_DELTA_ADDED);
+		bool in_index = (h2i && h2i->status != GIT_DELTA_DELETED);
+		bool in_wd    = (i2w && i2w->status != GIT_DELTA_DELETED);
+
+		if ((!in_tree || h2i->old_file.mode == GIT_FILEMODE_COMMIT) &&
+			(!in_index || h2i->new_file.mode == GIT_FILEMODE_COMMIT) &&
+			(!in_wd || i2w->new_file.mode == GIT_FILEMODE_COMMIT))
+			return 0;
 	}
 
 	return usercb->cb(path, status, usercb->payload);
@@ -109,7 +124,7 @@ int git_status_foreach_ext(
 {
 	int err = 0;
 	git_diff_options diffopt = GIT_DIFF_OPTIONS_INIT;
-	git_diff_list *idx2head = NULL, *wd2idx = NULL;
+	git_diff_list *head2idx = NULL, *idx2wd = NULL;
 	git_tree *head = NULL;
 	git_status_show_t show =
 		opts ? opts->show : GIT_STATUS_SHOW_INDEX_AND_WORKDIR;
@@ -144,33 +159,40 @@ int git_status_foreach_ext(
 		diffopt.flags = diffopt.flags | GIT_DIFF_DISABLE_PATHSPEC_MATCH;
 	if ((opts->flags & GIT_STATUS_OPT_RECURSE_IGNORED_DIRS) != 0)
 		diffopt.flags = diffopt.flags | GIT_DIFF_RECURSE_IGNORED_DIRS;
+	if ((opts->flags & GIT_STATUS_OPT_EXCLUDE_SUBMODULES) != 0)
+		diffopt.flags = diffopt.flags | GIT_DIFF_IGNORE_SUBMODULES;
 
-	if (show != GIT_STATUS_SHOW_WORKDIR_ONLY &&
-		(err = git_diff_tree_to_index(&idx2head, repo, head, NULL, &diffopt)) < 0)
-		goto cleanup;
+	if (show != GIT_STATUS_SHOW_WORKDIR_ONLY) {
+		err = git_diff_tree_to_index(&head2idx, repo, head, NULL, &diffopt);
+		if (err < 0)
+			goto cleanup;
+	}
 
-	if (show != GIT_STATUS_SHOW_INDEX_ONLY &&
-		(err = git_diff_index_to_workdir(&wd2idx, repo, NULL, &diffopt)) < 0)
-		goto cleanup;
+	if (show != GIT_STATUS_SHOW_INDEX_ONLY) {
+		err = git_diff_index_to_workdir(&idx2wd, repo, NULL, &diffopt);
+		if (err < 0)
+			goto cleanup;
+	}
 
 	usercb.cb = cb;
 	usercb.payload = payload;
+	usercb.opts = opts;
 
 	if (show == GIT_STATUS_SHOW_INDEX_THEN_WORKDIR) {
 		if ((err = git_diff__paired_foreach(
-				 idx2head, NULL, status_invoke_cb, &usercb)) < 0)
+				 head2idx, NULL, status_invoke_cb, &usercb)) < 0)
 			goto cleanup;
 
-		git_diff_list_free(idx2head);
-		idx2head = NULL;
+		git_diff_list_free(head2idx);
+		head2idx = NULL;
 	}
 
-	err = git_diff__paired_foreach(idx2head, wd2idx, status_invoke_cb, &usercb);
+	err = git_diff__paired_foreach(head2idx, idx2wd, status_invoke_cb, &usercb);
 
 cleanup:
 	git_tree_free(head);
-	git_diff_list_free(idx2head);
-	git_diff_list_free(wd2idx);
+	git_diff_list_free(head2idx);
+	git_diff_list_free(idx2wd);
 
 	if (err == GIT_EUSER)
 		giterr_clear();
diff --git a/src/submodule.c b/src/submodule.c
index 957766d..066a881 100644
--- a/src/submodule.c
+++ b/src/submodule.c
@@ -694,7 +694,7 @@ int git_submodule_open(
 	git_buf_free(&path);
 
 	/* if we have opened the submodule successfully, let's grab the HEAD OID */
-	if (!error && !(submodule->flags & GIT_SUBMODULE_STATUS__WD_OID_VALID)) {
+	if (!error) {
 		if (!git_reference_name_to_id(
 				&submodule->wd_oid, *subrepo, GIT_HEAD_FILE))
 			submodule->flags |= GIT_SUBMODULE_STATUS__WD_OID_VALID;
diff --git a/tests-clar/status/ignore.c b/tests-clar/status/ignore.c
index d40af7e..65ab472 100644
--- a/tests-clar/status/ignore.c
+++ b/tests-clar/status/ignore.c
@@ -245,10 +245,7 @@ void test_status_ignore__subdirectories_recursion(void)
 		GIT_STATUS_IGNORED,
 	};
 
-	opts.flags = GIT_STATUS_OPT_INCLUDE_IGNORED |
-		GIT_STATUS_OPT_RECURSE_IGNORED_DIRS |
-		GIT_STATUS_OPT_INCLUDE_UNTRACKED |
-		GIT_STATUS_OPT_RECURSE_UNTRACKED_DIRS;
+	opts.flags = GIT_STATUS_OPT_DEFAULTS | GIT_STATUS_OPT_RECURSE_IGNORED_DIRS;
 
 	g_repo = cl_git_sandbox_init("empty_standard_repo");
 
diff --git a/tests-clar/status/submodules.c b/tests-clar/status/submodules.c
index 24dd660..aa88f06 100644
--- a/tests-clar/status/submodules.c
+++ b/tests-clar/status/submodules.c
@@ -71,31 +71,34 @@ static unsigned int expected_status[] = {
 	GIT_STATUS_WT_NEW
 };
 
-static int
-cb_status__match(const char *p, unsigned int s, void *payload)
+static int cb_status__match(const char *p, unsigned int s, void *payload)
 {
-	volatile int *index = (int *)payload;
+	status_entry_counts *counts = payload;
+	int idx = counts->entry_count++;
 
-	cl_assert_equal_s(expected_files[*index], p);
-	cl_assert(expected_status[*index] == s);
-	(*index)++;
+	cl_assert_equal_s(counts->expected_paths[idx], p);
+	cl_assert(counts->expected_statuses[idx] == s);
 
 	return 0;
 }
 
 void test_status_submodules__1(void)
 {
-	int index = 0;
+	status_entry_counts counts;
 
 	cl_assert(git_path_isdir("submodules/.git"));
 	cl_assert(git_path_isdir("submodules/testrepo/.git"));
 	cl_assert(git_path_isfile("submodules/.gitmodules"));
 
+	memset(&counts, 0, sizeof(counts));
+	counts.expected_paths = expected_files;
+	counts.expected_statuses = expected_status;
+
 	cl_git_pass(
-		git_status_foreach(g_repo, cb_status__match, &index)
+		git_status_foreach(g_repo, cb_status__match, &counts)
 	);
 
-	cl_assert_equal_i(6, index);
+	cl_assert_equal_i(6, counts.entry_count);
 }
 
 void test_status_submodules__single_file(void)
@@ -104,3 +107,62 @@ void test_status_submodules__single_file(void)
 	cl_git_pass( git_status_file(&status, g_repo, "testrepo") );
 	cl_assert(!status);
 }
+
+void test_status_submodules__moved_head(void)
+{
+	git_submodule *sm;
+	git_repository *smrepo;
+	git_oid oid;
+	git_status_options opts = GIT_STATUS_OPTIONS_INIT;
+	status_entry_counts counts;
+	static const char *expected_files_with_sub[] = {
+		".gitmodules",
+		"added",
+		"deleted",
+		"ignored",
+		"modified",
+		"testrepo",
+		"untracked"
+	};
+	static unsigned int expected_status_with_sub[] = {
+		GIT_STATUS_WT_MODIFIED,
+		GIT_STATUS_INDEX_NEW,
+		GIT_STATUS_INDEX_DELETED,
+		GIT_STATUS_IGNORED,
+		GIT_STATUS_WT_MODIFIED,
+		GIT_STATUS_WT_MODIFIED,
+		GIT_STATUS_WT_NEW
+	};
+
+	cl_git_pass(git_submodule_lookup(&sm, g_repo, "testrepo"));
+	cl_git_pass(git_submodule_open(&smrepo, sm));
+
+	/* move submodule HEAD to c47800c7266a2be04c571c04d5a6614691ea99bd */
+	cl_git_pass(
+		git_oid_fromstr(&oid, "c47800c7266a2be04c571c04d5a6614691ea99bd"));
+	cl_git_pass(git_repository_set_head_detached(smrepo, &oid));
+
+	/* first do a normal status, which should now include the submodule */
+
+	memset(&counts, 0, sizeof(counts));
+	counts.expected_paths = expected_files_with_sub;
+	counts.expected_statuses = expected_status_with_sub;
+
+	opts.flags = GIT_STATUS_OPT_DEFAULTS;
+
+	cl_git_pass(
+		git_status_foreach_ext(g_repo, &opts, cb_status__match, &counts));
+	cl_assert_equal_i(7, counts.entry_count);
+
+	/* try again with EXCLUDE_SUBMODULES which should skip it */
+
+	memset(&counts, 0, sizeof(counts));
+	counts.expected_paths = expected_files;
+	counts.expected_statuses = expected_status;
+
+	opts.flags = GIT_STATUS_OPT_DEFAULTS | GIT_STATUS_OPT_EXCLUDE_SUBMODULES;
+
+	cl_git_pass(
+		git_status_foreach_ext(g_repo, &opts, cb_status__match, &counts));
+	cl_assert_equal_i(6, counts.entry_count);
+}