diff --git a/tests/index/collision.c b/tests/index/collision.c
index 19c1548e9..ad5827e0b 100644
--- a/tests/index/collision.c
+++ b/tests/index/collision.c
@@ -2,105 +2,103 @@
 #include "git2/repository.h"
 #include "git2/index.h"
 
-git_repository *repo = NULL;
+static git_repository *g_repo;
+static git_odb *g_odb;
+static git_index *g_index;
+static git_oid g_empty_id;
+
+void test_index_collision__initialize(void)
+{
+	g_repo = cl_git_sandbox_init("empty_standard_repo");
+	cl_git_pass(git_repository_odb(&g_odb, g_repo));
+	cl_git_pass(git_repository_index(&g_index, g_repo));
+
+	cl_git_pass(git_odb_write(&g_empty_id, g_odb, "", 0, GIT_OBJ_BLOB));
+}
 
 void test_index_collision__cleanup(void)
 {
+	git_index_free(g_index);
+	git_odb_free(g_odb);
 	cl_git_sandbox_cleanup();
-	repo = NULL;
 }
 
 void test_index_collision__add(void)
 {
-	git_index *index;
 	git_index_entry entry;
 	git_oid tree_id;
 	git_tree *tree;
 
-	repo = cl_git_sandbox_init("empty_standard_repo");
-	cl_git_pass(git_repository_index(&index, repo));
-
 	memset(&entry, 0, sizeof(entry));
 	entry.ctime.seconds = 12346789;
 	entry.mtime.seconds = 12346789;
 	entry.mode  = 0100644;
 	entry.file_size = 0;
-	git_oid_fromstr(&entry.id, "e69de29bb2d1d6434b8b29ae775ad8c2e48c5391");
+	git_oid_cpy(&entry.id, &g_empty_id);
 
 	entry.path = "a/b";
-	cl_git_pass(git_index_add(index, &entry));
+	cl_git_pass(git_index_add(g_index, &entry));
 
 	/* create a tree/blob collision */
 	entry.path = "a/b/c";
-	cl_git_fail(git_index_add(index, &entry));
+	cl_git_fail(git_index_add(g_index, &entry));
 
-	cl_git_pass(git_index_write_tree(&tree_id, index));
-	cl_git_pass(git_tree_lookup(&tree, repo, &tree_id));
+	cl_git_pass(git_index_write_tree(&tree_id, g_index));
+	cl_git_pass(git_tree_lookup(&tree, g_repo, &tree_id));
 
 	git_tree_free(tree);
-	git_index_free(index);
 }
 
 void test_index_collision__add_with_highstage_1(void)
 {
-	git_index *index;
 	git_index_entry entry;
 
-	repo = cl_git_sandbox_init("empty_standard_repo");
-	cl_git_pass(git_repository_index(&index, repo));
-
 	memset(&entry, 0, sizeof(entry));
 	entry.ctime.seconds = 12346789;
 	entry.mtime.seconds = 12346789;
 	entry.mode  = 0100644;
 	entry.file_size = 0;
-	git_oid_fromstr(&entry.id, "e69de29bb2d1d6434b8b29ae775ad8c2e48c5391");
+	git_oid_cpy(&entry.id, &g_empty_id);
 
 	entry.path = "a/b";
 	GIT_IDXENTRY_STAGE_SET(&entry, 2);
-	cl_git_pass(git_index_add(index, &entry));
+	cl_git_pass(git_index_add(g_index, &entry));
 
 	/* create a blob beneath the previous tree entry */
 	entry.path = "a/b/c";
 	entry.flags = 0;
-	cl_git_pass(git_index_add(index, &entry));
+	cl_git_pass(git_index_add(g_index, &entry));
 
 	/* create another tree entry above the blob */
 	entry.path = "a/b";
 	GIT_IDXENTRY_STAGE_SET(&entry, 1);
-	cl_git_pass(git_index_add(index, &entry));
-
-	git_index_free(index);
+	cl_git_pass(git_index_add(g_index, &entry));
 }
 
 void test_index_collision__add_with_highstage_2(void)
 {
-	git_index *index;
 	git_index_entry entry;
 
-	repo = cl_git_sandbox_init("empty_standard_repo");
-	cl_git_pass(git_repository_index(&index, repo));
+	cl_git_pass(git_repository_index(&g_index, g_repo));
 
 	memset(&entry, 0, sizeof(entry));
 	entry.ctime.seconds = 12346789;
 	entry.mtime.seconds = 12346789;
 	entry.mode  = 0100644;
 	entry.file_size = 0;
-	git_oid_fromstr(&entry.id, "e69de29bb2d1d6434b8b29ae775ad8c2e48c5391");
+	git_oid_cpy(&entry.id, &g_empty_id);
 
 	entry.path = "a/b/c";
 	GIT_IDXENTRY_STAGE_SET(&entry, 1);
-	cl_git_pass(git_index_add(index, &entry));
+	cl_git_pass(git_index_add(g_index, &entry));
 
 	/* create a blob beneath the previous tree entry */
 	entry.path = "a/b/c";
 	GIT_IDXENTRY_STAGE_SET(&entry, 2);
-	cl_git_pass(git_index_add(index, &entry));
+	cl_git_pass(git_index_add(g_index, &entry));
 
 	/* create another tree entry above the blob */
 	entry.path = "a/b";
 	GIT_IDXENTRY_STAGE_SET(&entry, 3);
-	cl_git_pass(git_index_add(index, &entry));
-
-	git_index_free(index);
+	cl_git_pass(git_index_add(g_index, &entry));
 }
diff --git a/tests/reset/hard.c b/tests/reset/hard.c
index e461f8093..69ef41e50 100644
--- a/tests/reset/hard.c
+++ b/tests/reset/hard.c
@@ -240,14 +240,18 @@ void test_reset_hard__switch_file_to_dir(void)
 {
 	git_index_entry entry = {{ 0 }};
 	git_index *idx;
+	git_odb *odb;
 	git_object *commit;
 	git_tree *tree;
 	git_signature *sig;
 	git_oid src_tree_id, tgt_tree_id;
 	git_oid src_id, tgt_id;
 
+	cl_git_pass(git_repository_odb(&odb, repo));
+	cl_git_pass(git_odb_write(&entry.id, odb, "", 0, GIT_OBJ_BLOB));
+	git_odb_free(odb);
+
 	entry.mode = GIT_FILEMODE_BLOB;
-	cl_git_pass(git_oid_fromstr(&entry.id, "e69de29bb2d1d6434b8b29ae775ad8c2e48c5391"));
 	cl_git_pass(git_index_new(&idx));
 	cl_git_pass(git_signature_now(&sig, "foo", "bar"));