test(local-storage): add unit tests

tests/LocalStorage/LocalStoragePrimitive.test.ts

@@ -0,0 +1,61 @@
+import { render } from "@testing-library/svelte";
+import LocalStoragePrimitive from "./LocalStoragePrimitive.test.svelte";
+
+describe("LocalStorage - Primitive Values", () => {
+  let localStorageMock: { [key: string]: string };
+  let originalLocalStorage: Storage;
+  let consoleSpy: any;
+
+  beforeEach(() => {
+    originalLocalStorage = global.localStorage;
+    localStorageMock = {};
+    consoleSpy = vi.spyOn(console, "log");
+
+    global.localStorage = {
+      getItem: vi.fn((key) => localStorageMock[key] || null),
+      setItem: vi.fn((key, value) => {
+        localStorageMock[key] = value;
+      }),
+      removeItem: vi.fn((key) => {
+        delete localStorageMock[key];
+      }),
+      clear: vi.fn(() => {
+        localStorageMock = {};
+      }),
+      length: 0,
+      key: vi.fn(),
+    };
+  });
+
+  afterEach(() => {
+    global.localStorage = originalLocalStorage;
+    localStorage.clear();
+    vi.restoreAllMocks();
+    localStorageMock = {};
+  });
+
+  it("saves primitive value to localStorage on mount", () => {
+    render(LocalStoragePrimitive);
+
+    expect(localStorage.setItem).toHaveBeenCalledWith("test-key", "test-value");
+  });
+
+  it("loads existing primitive value from localStorage", () => {
+    localStorageMock["test-key"] = "existing-value";
+
+    render(LocalStoragePrimitive);
+    expect(localStorage.getItem).toHaveBeenCalledWith("test-key");
+  });
+
+  it("dispatches save event when setting initial value", () => {
+    render(LocalStoragePrimitive);
+    expect(consoleSpy).toHaveBeenCalledWith("save event");
+  });
+
+  it("handles invalid values gracefully", () => {
+    localStorageMock["test-key"] = "{invalid-value}";
+
+    render(LocalStoragePrimitive);
+    expect(localStorage.getItem).toHaveBeenCalledWith("test-key");
+  });
+});