diff --git a/test/unit/main.test.ts b/test/unit/main.test.ts
index 614c830..9aef876 100644
--- a/test/unit/main.test.ts
+++ b/test/unit/main.test.ts
@@ -22,4 +22,16 @@ describe("main", () => {
   it("should return void when called with no context", () => {
     assert.isUndefined(loop());
   });
+
+  it("Automatically delete memory of missing creeps", () => {
+    Memory.creeps.persistValue = "any value";
+    Memory.creeps.notPersistValue = "any value";
+
+    Game.creeps.persistValue = "any value";
+
+    loop();
+
+    assert.isDefined(Memory.creeps.persistValue);
+    assert.isUndefined(Memory.creeps.notPersistValue);
+  });
 });
diff --git a/test/unit/mock.ts b/test/unit/mock.ts
index a7a868f..add6585 100644
--- a/test/unit/mock.ts
+++ b/test/unit/mock.ts
@@ -1,10 +1,17 @@
-export const Game = {
-  creeps: [],
+export const Game: {
+  creeps: { [name: string]: any };
+  rooms: any;
+  spawns: any;
+  time: any;
+} = {
+  creeps: {},
   rooms: [],
   spawns: {},
   time: 12345
 };
 
-export const Memory = {
-  creeps: []
+export const Memory: {
+  creeps: { [name: string]: any };
+} = {
+  creeps: {}
 };