thodg/libgit2

diff --git a/include/git2/status.h b/include/git2/status.h
index 6a424df..69b6e47 100644
--- a/include/git2/status.h
+++ b/include/git2/status.h
@@ -102,7 +102,7 @@ enum {
 	GIT_STATUS_OPT_INCLUDE_UNTRACKED = (1 << 0),
 	GIT_STATUS_OPT_INCLUDE_IGNORED = (1 << 1),
 	GIT_STATUS_OPT_INCLUDE_UNMODIFIED = (1 << 2),
-	GIT_STATUS_OPT_EXCLUDE_SUBMODULED = (1 << 3),
+	GIT_STATUS_OPT_EXCLUDE_SUBMODULES = (1 << 3),
 	GIT_STATUS_OPT_RECURSE_UNTRACKED_DIRS = (1 << 4),
 };
 
diff --git a/src/diff.c b/src/diff.c
index 90baa95..e3167b9 100644
--- a/src/diff.c
+++ b/src/diff.c
@@ -214,7 +214,9 @@ static int diff_delta__from_two(
 	git_diff_list *diff,
 	git_delta_t   status,
 	const git_index_entry *old_entry,
+	uint32_t old_mode,
 	const git_index_entry *new_entry,
+	uint32_t new_mode,
 	git_oid *new_oid)
 {
 	git_diff_delta *delta;
@@ -224,19 +226,22 @@ static int diff_delta__from_two(
 		return 0;
 
 	if ((diff->opts.flags & GIT_DIFF_REVERSE) != 0) {
-		const git_index_entry *temp = old_entry;
+		uint32_t temp_mode = old_mode;
+		const git_index_entry *temp_entry = old_entry;
 		old_entry = new_entry;
-		new_entry = temp;
+		new_entry = temp_entry;
+		old_mode = new_mode;
+		new_mode = temp_mode;
 	}
 
 	delta = diff_delta__alloc(diff, status, old_entry->path);
 	GITERR_CHECK_ALLOC(delta);
 
-	delta->old_file.mode = old_entry->mode;
+	delta->old_file.mode = old_mode;
 	git_oid_cpy(&delta->old_file.oid, &old_entry->oid);
 	delta->old_file.flags |= GIT_DIFF_FILE_VALID_OID;
 
-	delta->new_file.mode = new_entry->mode;
+	delta->new_file.mode = new_mode;
 	git_oid_cpy(&delta->new_file.oid, new_oid ? new_oid : &new_entry->oid);
 	if (new_oid || !git_oid_iszero(&new_entry->oid))
 		delta->new_file.flags |= GIT_DIFF_FILE_VALID_OID;
@@ -300,7 +305,7 @@ static git_diff_list *git_diff_list_alloc(
 	if (config_bool(cfg, "core.ignorestat", 0))
 		diff->diffcaps = diff->diffcaps | GIT_DIFFCAPS_ASSUME_UNCHANGED;
 	if (config_bool(cfg, "core.filemode", 1))
-		diff->diffcaps = diff->diffcaps | GIT_DIFFCAPS_TRUST_EXEC_BIT;
+		diff->diffcaps = diff->diffcaps | GIT_DIFFCAPS_TRUST_MODE_BITS;
 	if (config_bool(cfg, "core.trustctime", 1))
 		diff->diffcaps = diff->diffcaps | GIT_DIFFCAPS_TRUST_CTIME;
 	/* Don't set GIT_DIFFCAPS_USE_DEV - compile time option in core git */
@@ -419,7 +424,7 @@ static int oid_for_workdir_item(
 	return result;
 }
 
-#define EXEC_BIT_MASK 0000111
+#define MODE_BITS_MASK 0000777
 
 static int maybe_modified(
 	git_iterator *old_iter,
@@ -443,13 +448,13 @@ static int maybe_modified(
 		!(diff->diffcaps & GIT_DIFFCAPS_HAS_SYMLINKS))
 		nmode = GIT_MODE_TYPE(omode) | (nmode & GIT_MODE_PERMS_MASK);
 
-	/* on platforms with no execmode, clear exec bit from comparisons */
-	if (!(diff->diffcaps & GIT_DIFFCAPS_TRUST_EXEC_BIT)) {
-		omode = omode & ~EXEC_BIT_MASK;
-		nmode = nmode & ~EXEC_BIT_MASK;
-	}
+	/* on platforms with no execmode, just preserve old mode */
+	if (!(diff->diffcaps & GIT_DIFFCAPS_TRUST_MODE_BITS) &&
+		(nmode & MODE_BITS_MASK) != (omode & MODE_BITS_MASK) &&
+		new_iter->type == GIT_ITERATOR_WORKDIR)
+		nmode = (nmode & ~MODE_BITS_MASK) | (omode & MODE_BITS_MASK);
 
-	/* support "assume unchanged" (badly, b/c we still stat everything) */
+	/* support "assume unchanged" (poorly, b/c we still stat everything) */
 	if ((diff->diffcaps & GIT_DIFFCAPS_ASSUME_UNCHANGED) != 0)
 		status = (oitem->flags_extended & GIT_IDXENTRY_INTENT_TO_ADD) ?
 			GIT_DELTA_MODIFIED : GIT_DELTA_UNMODIFIED;
@@ -471,8 +476,13 @@ static int maybe_modified(
 			 omode == nmode)
 		status = GIT_DELTA_UNMODIFIED;
 
-	/* if we have a workdir item with an unknown oid, check deeper */
-	else if (git_oid_iszero(&nitem->oid) && new_iter->type == GIT_ITERATOR_WORKDIR) {
+	/* if modes match and we have an unknown OID and a workdir iterator,
+	 * then check deeper for matching
+	 */
+	else if (omode == nmode &&
+		git_oid_iszero(&nitem->oid) &&
+		new_iter->type == GIT_ITERATOR_WORKDIR)
+	{
 		/* TODO: add check against index file st_mtime to avoid racy-git */
 
 		/* if they files look exactly alike, then we'll assume the same */
@@ -517,7 +527,8 @@ static int maybe_modified(
 		use_noid = &noid;
 	}
 
-	return diff_delta__from_two(diff, status, oitem, nitem, use_noid);
+	return diff_delta__from_two(
+		diff, status, oitem, omode, nitem, nmode, use_noid);
 }
 
 static int diff_from_iterators(
diff --git a/src/diff.h b/src/diff.h
index ac24579..6cc854f 100644
--- a/src/diff.h
+++ b/src/diff.h
@@ -20,7 +20,7 @@
 enum {
 	GIT_DIFFCAPS_HAS_SYMLINKS     = (1 << 0), /* symlinks on platform? */
 	GIT_DIFFCAPS_ASSUME_UNCHANGED = (1 << 1), /* use stat? */
-	GIT_DIFFCAPS_TRUST_EXEC_BIT   = (1 << 2), /* use st_mode exec bit? */
+	GIT_DIFFCAPS_TRUST_MODE_BITS  = (1 << 2), /* use st_mode? */
 	GIT_DIFFCAPS_TRUST_CTIME      = (1 << 3), /* use st_ctime? */
 	GIT_DIFFCAPS_USE_DEV          = (1 << 4), /* use st_dev? */
 };
@@ -36,5 +36,8 @@ struct git_diff_list {
 	uint32_t diffcaps;
 };
 
+extern void git_diff__cleanup_modes(
+	uint32_t diffcaps, uint32_t *omode, uint32_t *nmode);
+
 #endif
 
diff --git a/src/diff_output.c b/src/diff_output.c
index 1c65e1b..d1aa910 100644
--- a/src/diff_output.c
+++ b/src/diff_output.c
@@ -359,7 +359,7 @@ int git_diff_foreach(
 
 		/* map files */
 		if (delta->binary != 1 &&
-			(hunk_cb || line_cb) &&
+			(hunk_cb || line_cb || git_oid_iszero(&delta->old_file.oid)) &&
 			(delta->status == GIT_DELTA_DELETED ||
 			 delta->status == GIT_DELTA_MODIFIED))
 		{
@@ -397,7 +397,9 @@ int git_diff_foreach(
 				/* since we did not have the definitive oid, we may have
 				 * incorrect status and need to skip this item.
 				 */
-				if (git_oid_cmp(&delta->old_file.oid, &delta->new_file.oid) == 0) {
+				if (delta->old_file.mode == delta->new_file.mode &&
+					!git_oid_cmp(&delta->old_file.oid, &delta->new_file.oid))
+				{
 					delta->status = GIT_DELTA_UNMODIFIED;
 					if ((diff->opts.flags & GIT_DIFF_INCLUDE_UNMODIFIED) == 0)
 						goto cleanup;
@@ -420,7 +422,8 @@ int git_diff_foreach(
 		 */
 
 		if (file_cb != NULL) {
-			error = file_cb(data, delta, (float)info.index / diff->deltas.length);
+			error = file_cb(
+				data, delta, (float)info.index / diff->deltas.length);
 			if (error < 0)
 				goto cleanup;
 		}
@@ -433,6 +436,10 @@ int git_diff_foreach(
 		if (!old_data.len && !new_data.len)
 			goto cleanup;
 
+		/* nothing to do if only diff was a mode change */
+		if (!git_oid_cmp(&delta->old_file.oid, &delta->new_file.oid))
+			goto cleanup;
+
 		assert(hunk_cb || line_cb);
 
 		info.delta = delta;
diff --git a/tests-clar/clar_helpers.c b/tests-clar/clar_helpers.c
index 23765d9..1275d16 100644
--- a/tests-clar/clar_helpers.c
+++ b/tests-clar/clar_helpers.c
@@ -155,3 +155,27 @@ void cl_git_sandbox_cleanup(void)
 	}
 }
 
+bool cl_toggle_filemode(const char *filename)
+{
+	struct stat st1, st2;
+
+	cl_must_pass(p_stat(filename, &st1));
+	cl_must_pass(p_chmod(filename, st1.st_mode ^ 0100));
+	cl_must_pass(p_stat(filename, &st2));
+
+	return (st1.st_mode != st2.st_mode);
+}
+
+bool cl_is_chmod_supported(void)
+{
+	static int _is_supported = -1;
+
+	if (_is_supported < 0) {
+		cl_git_mkfile("filemode.t", "Test if filemode can be modified");
+		_is_supported = cl_toggle_filemode("filemode.t");
+		cl_must_pass(p_unlink("filemode.t"));
+	}
+
+	return _is_supported;
+}
+
diff --git a/tests-clar/clar_libgit2.h b/tests-clar/clar_libgit2.h
index aa613b2..a3b03bb 100644
--- a/tests-clar/clar_libgit2.h
+++ b/tests-clar/clar_libgit2.h
@@ -40,6 +40,9 @@ void cl_git_append2file(const char *filename, const char *new_content);
 void cl_git_rewritefile(const char *filename, const char *new_content);
 void cl_git_write2file(const char *filename, const char *new_content, int mode);
 
+bool cl_toggle_filemode(const char *filename);
+bool cl_is_chmod_supported(void);
+
 /* Environment wrappers */
 char *cl_getenv(const char *name);
 int cl_setenv(const char *name, const char *value);
diff --git a/tests-clar/diff/workdir.c b/tests-clar/diff/workdir.c
index 42152f1..354c996 100644
--- a/tests-clar/diff/workdir.c
+++ b/tests-clar/diff/workdir.c
@@ -5,7 +5,6 @@ static git_repository *g_repo = NULL;
 
 void test_diff_workdir__initialize(void)
 {
-	g_repo = cl_git_sandbox_init("status");
 }
 
 void test_diff_workdir__cleanup(void)
@@ -19,6 +18,8 @@ void test_diff_workdir__to_index(void)
 	git_diff_list *diff = NULL;
 	diff_expects exp;
 
+	g_repo = cl_git_sandbox_init("status");
+
 	opts.context_lines = 3;
 	opts.interhunk_lines = 1;
 	opts.flags |= GIT_DIFF_INCLUDE_IGNORED | GIT_DIFF_INCLUDE_UNTRACKED;
@@ -59,13 +60,17 @@ void test_diff_workdir__to_tree(void)
 	/* grabbed a couple of commit oids from the history of the attr repo */
 	const char *a_commit = "26a125ee1bf"; /* the current HEAD */
 	const char *b_commit = "0017bd4ab1ec3"; /* the start */
-	git_tree *a = resolve_commit_oid_to_tree(g_repo, a_commit);
-	git_tree *b = resolve_commit_oid_to_tree(g_repo, b_commit);
+	git_tree *a, *b;
 	git_diff_options opts = {0};
 	git_diff_list *diff = NULL;
 	git_diff_list *diff2 = NULL;
 	diff_expects exp;
 
+	g_repo = cl_git_sandbox_init("status");
+
+	a = resolve_commit_oid_to_tree(g_repo, a_commit);
+	b = resolve_commit_oid_to_tree(g_repo, b_commit);
+
 	opts.context_lines = 3;
 	opts.interhunk_lines = 1;
 	opts.flags |= GIT_DIFF_INCLUDE_IGNORED | GIT_DIFF_INCLUDE_UNTRACKED;
@@ -171,6 +176,8 @@ void test_diff_workdir__to_index_with_pathspec(void)
 	diff_expects exp;
 	char *pathspec = NULL;
 
+	g_repo = cl_git_sandbox_init("status");
+
 	opts.context_lines = 3;
 	opts.interhunk_lines = 1;
 	opts.flags |= GIT_DIFF_INCLUDE_IGNORED | GIT_DIFF_INCLUDE_UNTRACKED;
@@ -237,6 +244,102 @@ void test_diff_workdir__to_index_with_pathspec(void)
 	git_diff_list_free(diff);
 }
 
+void test_diff_workdir__filemode_changes(void)
+{
+	git_config *cfg;
+	git_diff_list *diff = NULL;
+	diff_expects exp;
+
+	if (!cl_is_chmod_supported())
+		return;
+
+	g_repo = cl_git_sandbox_init("issue_592");
+
+	cl_git_pass(git_repository_config(&cfg, g_repo));
+	cl_git_pass(git_config_set_bool(cfg, "core.filemode", true));
+
+	/* test once with no mods */
+
+	cl_git_pass(git_diff_workdir_to_index(g_repo, NULL, &diff));
+
+	memset(&exp, 0, sizeof(exp));
+	cl_git_pass(git_diff_foreach(
+		diff, &exp, diff_file_fn, diff_hunk_fn, diff_line_fn));
+
+	cl_assert_equal_i(0, exp.files);
+	cl_assert_equal_i(0, exp.file_mods);
+	cl_assert_equal_i(0, exp.hunks);
+
+	git_diff_list_free(diff);
+
+	/* chmod file and test again */
+
+	cl_assert(cl_toggle_filemode("issue_592/a.txt"));
+
+	cl_git_pass(git_diff_workdir_to_index(g_repo, NULL, &diff));
+
+	memset(&exp, 0, sizeof(exp));
+	cl_git_pass(git_diff_foreach(
+		diff, &exp, diff_file_fn, diff_hunk_fn, diff_line_fn));
+
+	cl_assert_equal_i(1, exp.files);
+	cl_assert_equal_i(1, exp.file_mods);
+	cl_assert_equal_i(0, exp.hunks);
+
+	git_diff_list_free(diff);
+
+	cl_assert(cl_toggle_filemode("issue_592/a.txt"));
+	git_config_free(cfg);
+}
+
+void test_diff_workdir__filemode_changes_with_filemode_false(void)
+{
+	git_config *cfg;
+	git_diff_list *diff = NULL;
+	diff_expects exp;
+
+	if (!cl_is_chmod_supported())
+		return;
+
+	g_repo = cl_git_sandbox_init("issue_592");
+
+	cl_git_pass(git_repository_config(&cfg, g_repo));
+	cl_git_pass(git_config_set_bool(cfg, "core.filemode", false));
+
+	/* test once with no mods */
+
+	cl_git_pass(git_diff_workdir_to_index(g_repo, NULL, &diff));
+
+	memset(&exp, 0, sizeof(exp));
+	cl_git_pass(git_diff_foreach(
+		diff, &exp, diff_file_fn, diff_hunk_fn, diff_line_fn));
+
+	cl_assert_equal_i(0, exp.files);
+	cl_assert_equal_i(0, exp.file_mods);
+	cl_assert_equal_i(0, exp.hunks);
+
+	git_diff_list_free(diff);
+
+	/* chmod file and test again */
+
+	cl_assert(cl_toggle_filemode("issue_592/a.txt"));
+
+	cl_git_pass(git_diff_workdir_to_index(g_repo, NULL, &diff));
+
+	memset(&exp, 0, sizeof(exp));
+	cl_git_pass(git_diff_foreach(
+		diff, &exp, diff_file_fn, diff_hunk_fn, diff_line_fn));
+
+	cl_assert_equal_i(0, exp.files);
+	cl_assert_equal_i(0, exp.file_mods);
+	cl_assert_equal_i(0, exp.hunks);
+
+	git_diff_list_free(diff);
+
+	cl_assert(cl_toggle_filemode("issue_592/a.txt"));
+	git_config_free(cfg);
+}
+
 /* PREPARATION OF TEST DATA
  *
  * Since there is no command line equivalent of git_diff_workdir_to_tree,
diff --git a/tests-clar/resources/filemodes/.gitted/HEAD b/tests-clar/resources/filemodes/.gitted/HEAD
new file mode 100644
index 0000000..cb089cd
--- /dev/null
+++ b/tests-clar/resources/filemodes/.gitted/HEAD
@@ -0,0 +1 @@
+ref: refs/heads/master
diff --git a/tests-clar/resources/filemodes/.gitted/config b/tests-clar/resources/filemodes/.gitted/config
new file mode 100644
index 0000000..af10792
--- /dev/null
+++ b/tests-clar/resources/filemodes/.gitted/config
@@ -0,0 +1,6 @@
+[core]
+	repositoryformatversion = 0
+	filemode = true
+	bare = false
+	logallrefupdates = true
+	ignorecase = true
diff --git a/tests-clar/resources/filemodes/.gitted/description b/tests-clar/resources/filemodes/.gitted/description
new file mode 100644
index 0000000..498b267
--- /dev/null
+++ b/tests-clar/resources/filemodes/.gitted/description
@@ -0,0 +1 @@
+Unnamed repository; edit this file 'description' to name the repository.
diff --git a/tests-clar/resources/filemodes/.gitted/hooks/commit-msg.sample b/tests-clar/resources/filemodes/.gitted/hooks/commit-msg.sample
new file mode 100755
index 0000000..b58d118
--- /dev/null
+++ b/tests-clar/resources/filemodes/.gitted/hooks/commit-msg.sample
@@ -0,0 +1,24 @@
+#!/bin/sh
+#
+# An example hook script to check the commit log message.
+# Called by "git commit" with one argument, the name of the file
+# that has the commit message.  The hook should exit with non-zero
+# status after issuing an appropriate message if it wants to stop the
+# commit.  The hook is allowed to edit the commit message file.
+#
+# To enable this hook, rename this file to "commit-msg".
+
+# Uncomment the below to add a Signed-off-by line to the message.
+# Doing this in a hook is a bad idea in general, but the prepare-commit-msg
+# hook is more suited to it.
+#
+# SOB=$(git var GIT_AUTHOR_IDENT | sed -n 's/^\(.*>\).*$/Signed-off-by: \1/p')
+# grep -qs "^$SOB" "$1" || echo "$SOB" >> "$1"
+
+# This example catches duplicate Signed-off-by lines.
+
+test "" = "$(grep '^Signed-off-by: ' "$1" |
+	 sort | uniq -c | sed -e '/^[ 	]*1[ 	]/d')" || {
+	echo >&2 Duplicate Signed-off-by lines.
+	exit 1
+}
diff --git a/tests-clar/resources/filemodes/.gitted/index b/tests-clar/resources/filemodes/.gitted/index
new file mode 100644
index 0000000..b1b175a
Binary files /dev/null and b/tests-clar/resources/filemodes/.gitted/index differ
diff --git a/tests-clar/resources/filemodes/.gitted/info/exclude b/tests-clar/resources/filemodes/.gitted/info/exclude
new file mode 100644
index 0000000..a5196d1
--- /dev/null
+++ b/tests-clar/resources/filemodes/.gitted/info/exclude
@@ -0,0 +1,6 @@
+# git ls-files --others --exclude-from=.git/info/exclude
+# Lines that start with '#' are comments.
+# For a project mostly in C, the following would be a good set of
+# exclude patterns (uncomment them if you want to use them):
+# *.[oa]
+# *~
diff --git a/tests-clar/resources/filemodes/.gitted/logs/HEAD b/tests-clar/resources/filemodes/.gitted/logs/HEAD
new file mode 100644
index 0000000..1cb6a84
--- /dev/null
+++ b/tests-clar/resources/filemodes/.gitted/logs/HEAD
@@ -0,0 +1 @@
+0000000000000000000000000000000000000000 9962c8453ba6f0cf8dac7c5dcc2fa2897fa9964a Russell Belfer <rb@github.com> 1338847682 -0700	commit (initial): Initial commit of test data
diff --git a/tests-clar/resources/filemodes/.gitted/logs/refs/heads/master b/tests-clar/resources/filemodes/.gitted/logs/refs/heads/master
new file mode 100644
index 0000000..1cb6a84
--- /dev/null
+++ b/tests-clar/resources/filemodes/.gitted/logs/refs/heads/master
@@ -0,0 +1 @@
+0000000000000000000000000000000000000000 9962c8453ba6f0cf8dac7c5dcc2fa2897fa9964a Russell Belfer <rb@github.com> 1338847682 -0700	commit (initial): Initial commit of test data
diff --git a/tests-clar/resources/filemodes/.gitted/objects/99/62c8453ba6f0cf8dac7c5dcc2fa2897fa9964a b/tests-clar/resources/filemodes/.gitted/objects/99/62c8453ba6f0cf8dac7c5dcc2fa2897fa9964a
new file mode 100644
index 0000000..cbd2b55
Binary files /dev/null and b/tests-clar/resources/filemodes/.gitted/objects/99/62c8453ba6f0cf8dac7c5dcc2fa2897fa9964a differ
diff --git a/tests-clar/resources/filemodes/.gitted/objects/a5/c5dd0fc6c313159a69b1d19d7f61a9f978e8f1 b/tests-clar/resources/filemodes/.gitted/objects/a5/c5dd0fc6c313159a69b1d19d7f61a9f978e8f1
new file mode 100644
index 0000000..a9eaf2c
Binary files /dev/null and b/tests-clar/resources/filemodes/.gitted/objects/a5/c5dd0fc6c313159a69b1d19d7f61a9f978e8f1 differ
diff --git a/tests-clar/resources/filemodes/.gitted/objects/e7/48d196331bcb20267eaaee4ff3326cb73b8182 b/tests-clar/resources/filemodes/.gitted/objects/e7/48d196331bcb20267eaaee4ff3326cb73b8182
new file mode 100644
index 0000000..9806602
Binary files /dev/null and b/tests-clar/resources/filemodes/.gitted/objects/e7/48d196331bcb20267eaaee4ff3326cb73b8182 differ
diff --git a/tests-clar/resources/filemodes/.gitted/refs/heads/master b/tests-clar/resources/filemodes/.gitted/refs/heads/master
new file mode 100644
index 0000000..9822d2d
--- /dev/null
+++ b/tests-clar/resources/filemodes/.gitted/refs/heads/master
@@ -0,0 +1 @@
+9962c8453ba6f0cf8dac7c5dcc2fa2897fa9964a
diff --git a/tests-clar/resources/filemodes/exec_off b/tests-clar/resources/filemodes/exec_off
new file mode 100644
index 0000000..a5c5dd0
--- /dev/null
+++ b/tests-clar/resources/filemodes/exec_off
@@ -0,0 +1 @@
+Howdy
diff --git a/tests-clar/resources/filemodes/exec_off2on_staged b/tests-clar/resources/filemodes/exec_off2on_staged
new file mode 100755
index 0000000..a5c5dd0
--- /dev/null
+++ b/tests-clar/resources/filemodes/exec_off2on_staged
@@ -0,0 +1 @@
+Howdy
diff --git a/tests-clar/resources/filemodes/exec_off2on_workdir b/tests-clar/resources/filemodes/exec_off2on_workdir
new file mode 100755
index 0000000..a5c5dd0
--- /dev/null
+++ b/tests-clar/resources/filemodes/exec_off2on_workdir
@@ -0,0 +1 @@
+Howdy
diff --git a/tests-clar/resources/filemodes/exec_off_untracked b/tests-clar/resources/filemodes/exec_off_untracked
new file mode 100644
index 0000000..a5c5dd0
--- /dev/null
+++ b/tests-clar/resources/filemodes/exec_off_untracked
@@ -0,0 +1 @@
+Howdy
diff --git a/tests-clar/resources/filemodes/exec_on b/tests-clar/resources/filemodes/exec_on
new file mode 100755
index 0000000..a5c5dd0
--- /dev/null
+++ b/tests-clar/resources/filemodes/exec_on
@@ -0,0 +1 @@
+Howdy
diff --git a/tests-clar/resources/filemodes/exec_on2off_staged b/tests-clar/resources/filemodes/exec_on2off_staged
new file mode 100644
index 0000000..a5c5dd0
--- /dev/null
+++ b/tests-clar/resources/filemodes/exec_on2off_staged
@@ -0,0 +1 @@
+Howdy
diff --git a/tests-clar/resources/filemodes/exec_on2off_workdir b/tests-clar/resources/filemodes/exec_on2off_workdir
new file mode 100644
index 0000000..a5c5dd0
--- /dev/null
+++ b/tests-clar/resources/filemodes/exec_on2off_workdir
@@ -0,0 +1 @@
+Howdy
diff --git a/tests-clar/resources/filemodes/exec_on_untracked b/tests-clar/resources/filemodes/exec_on_untracked
new file mode 100755
index 0000000..a5c5dd0
--- /dev/null
+++ b/tests-clar/resources/filemodes/exec_on_untracked
@@ -0,0 +1 @@
+Howdy
diff --git a/tests-clar/status/worktree.c b/tests-clar/status/worktree.c
index b3ebdb7..3670b72 100644
--- a/tests-clar/status/worktree.c
+++ b/tests-clar/status/worktree.c
@@ -581,3 +581,69 @@ void test_status_worktree__space_in_filename(void)
 	git_index_free(index);
 	git_repository_free(repo);
 }
+
+static const char *filemode_paths[] = {
+	"exec_off",
+	"exec_off2on_staged",
+	"exec_off2on_workdir",
+	"exec_off_untracked",
+	"exec_on",
+	"exec_on2off_staged",
+	"exec_on2off_workdir",
+	"exec_on_untracked",
+};
+
+static unsigned int filemode_statuses[] = {
+	GIT_STATUS_CURRENT,
+	GIT_STATUS_INDEX_MODIFIED,
+	GIT_STATUS_WT_MODIFIED,
+	GIT_STATUS_WT_NEW,
+	GIT_STATUS_CURRENT,
+	GIT_STATUS_INDEX_MODIFIED,
+	GIT_STATUS_WT_MODIFIED,
+	GIT_STATUS_WT_NEW
+};
+
+static const size_t filemode_count = 8;
+
+void test_status_worktree__filemode_changes(void)
+{
+	git_repository *repo = cl_git_sandbox_init("filemodes");
+	status_entry_counts counts;
+	git_status_options opts;
+	git_config *cfg;
+
+	/* overwrite stored filemode with platform appropriate value */
+	cl_git_pass(git_repository_config(&cfg, repo));
+	if (cl_is_chmod_supported())
+		cl_git_pass(git_config_set_bool(cfg, "core.filemode", true));
+	else {
+		unsigned int i;
+		cl_git_pass(git_config_set_bool(cfg, "core.filemode", false));
+
+		/* won't trust filesystem mode diffs, so these will appear unchanged */
+		for (i = 0; i < filemode_count; ++i)
+			if (filemode_statuses[i] == GIT_STATUS_WT_MODIFIED)
+				filemode_statuses[i] = GIT_STATUS_CURRENT;
+	}
+
+	memset(&opts, 0, sizeof(opts));
+	opts.flags = GIT_STATUS_OPT_INCLUDE_UNTRACKED |
+		GIT_STATUS_OPT_INCLUDE_IGNORED |
+		GIT_STATUS_OPT_INCLUDE_UNMODIFIED;
+
+	memset(&counts, 0, sizeof(counts));
+	counts.expected_entry_count = filemode_count;
+	counts.expected_paths = filemode_paths;
+	counts.expected_statuses = filemode_statuses;
+
+	cl_git_pass(
+		git_status_foreach_ext(repo, &opts, cb_status__normal, &counts)
+	);
+
+	cl_assert_equal_i(counts.expected_entry_count, counts.entry_count);
+	cl_assert_equal_i(0, counts.wrong_status_flags_count);
+	cl_assert_equal_i(0, counts.wrong_sorted_path);
+
+	git_config_free(cfg);
+}