Fix crash with adding internal ignores

Depending on what you had done before adding new items to the
internal ignores list, it was possible for the cache of ignore
data to be uninitialized.

2 files changed, 27 insertions, 8 deletions

diff --git a/src/ignore.c b/src/ignore.c
index 1ac8afdf..3c2f19ab 100644
--- a/src/ignore.c
+++ b/src/ignore.c
@@ -205,6 +205,16 @@ cleanup:
 	return 0;
 }
 
+static int get_internal_ignores(git_attr_file **ign, git_repository *repo)
+{
+	int error;
+
+	if (!(error = git_attr_cache__init(repo)))
+		error = git_attr_cache__internal_file(repo, GIT_IGNORE_INTERNAL, ign);
+
+	return error;
+}
+
 int git_ignore_add_rule(
 	git_repository *repo,
 	const char *rules)
@@ -212,10 +222,7 @@ int git_ignore_add_rule(
 	int error;
 	git_attr_file *ign_internal;
 
-	error = git_attr_cache__internal_file(
-		repo, GIT_IGNORE_INTERNAL, &ign_internal);
-
-	if (!error && ign_internal != NULL)
+	if (!(error = get_internal_ignores(&ign_internal, repo)))
 		error = parse_ignore_file(repo, rules, ign_internal);
 
 	return error;
@@ -227,10 +234,7 @@ int git_ignore_clear_internal_rules(
 	int error;
 	git_attr_file *ign_internal;
 
-	error = git_attr_cache__internal_file(
-		repo, GIT_IGNORE_INTERNAL, &ign_internal);
-
-	if (!error && ign_internal != NULL)
+	if (!(error = get_internal_ignores(&ign_internal, repo)))
 		git_attr_file__clear_rules(ign_internal);
 
 	return error;
diff --git a/tests-clar/status/ignore.c b/tests-clar/status/ignore.c
index 9c6d7ee6..9092d515 100644
--- a/tests-clar/status/ignore.c
+++ b/tests-clar/status/ignore.c
@@ -199,3 +199,18 @@ void test_status_ignore__adding_internal_ignores(void)
 	cl_git_pass(git_status_should_ignore(&ignored, g_repo, "two.bar"));
 	cl_assert(ignored);
 }
+
+void test_status_ignore__add_internal_as_first_thing(void)
+{
+	int ignored;
+	const char *add_me = "\n#################\n## Eclipse\n#################\n\n*.pydevproject\n.project\n.metadata\nbin/\ntmp/\n*.tmp\n\n";
+
+	g_repo = cl_git_sandbox_init("empty_standard_repo");
+
+	cl_git_pass(git_ignore_add_rule(g_repo, add_me));
+
+	cl_git_pass(git_status_should_ignore(&ignored, g_repo, "one.tmp"));
+	cl_assert(ignored);
+	cl_git_pass(git_status_should_ignore(&ignored, g_repo, "two.bar"));
+	cl_assert(!ignored);
+}