Fix filemode comparison in diffs

File modes were both not being ignored properly on platforms
where they should be ignored, nor be diffed consistently on
platforms where they are supported.

This change adds a number of diff and status filemode change
tests.  This also makes sure that filemode-only changes are
included in the diff output when they occur and that filemode
changes are ignored successfully when core.filemode is false.

There is no code that automatically toggles core.filemode
based on the capabilities of the current platform, so the user
still needs to be careful in their .git/config file.

1 files changed, 106 insertions, 3 deletions

diff --git a/tests-clar/diff/workdir.c b/tests-clar/diff/workdir.c
index 42152f1ad..354c99643 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,