1 files changed, 58 insertions, 0 deletions
diff --git a/tests/util/str/oom.c b/tests/util/str/oom.c
new file mode 100644
index 000000000..dd3796674
--- /dev/null
+++ b/tests/util/str/oom.c
@@ -0,0 +1,58 @@
+#include "clar_libgit2.h"
+
+/* Override default allocators with ones that will fail predictably. */
+
+static git_allocator std_alloc;
+static git_allocator oom_alloc;
+
+static void *oom_malloc(size_t n, const char *file, int line)
+{
+	/* Reject any allocation of more than 100 bytes */
+	return (n > 100) ? NULL : std_alloc.gmalloc(n, file, line);
+}
+
+static void *oom_realloc(void *p, size_t n, const char *file, int line)
+{
+	/* Reject any allocation of more than 100 bytes */
+	return (n > 100) ? NULL : std_alloc.grealloc(p, n, file, line);
+}
+
+void test_str_oom__initialize(void)
+{
+	git_stdalloc_init_allocator(&std_alloc);
+	git_stdalloc_init_allocator(&oom_alloc);
+
+	oom_alloc.gmalloc = oom_malloc;
+	oom_alloc.grealloc = oom_realloc;
+
+	cl_git_pass(git_allocator_setup(&oom_alloc));
+}
+
+void test_str_oom__cleanup(void)
+{
+	cl_git_pass(git_allocator_setup(NULL));
+}
+
+void test_str_oom__grow(void)
+{
+	git_str buf = GIT_STR_INIT;
+
+	cl_git_pass(git_str_grow(&buf, 42));
+	cl_assert(!git_str_oom(&buf));
+
+	cl_assert(git_str_grow(&buf, 101) == -1);
+	cl_assert(git_str_oom(&buf));
+
+	git_str_dispose(&buf);
+}
+
+void test_str_oom__grow_by(void)
+{
+	git_str buf = GIT_STR_INIT;
+
+	cl_git_pass(git_str_grow_by(&buf, 42));
+	cl_assert(!git_str_oom(&buf));
+
+	cl_assert(git_str_grow_by(&buf, 101) == -1);
+	cl_assert(git_str_oom(&buf));
+}