Added test for main.ts

tests/main.spec.ts

@@ -0,0 +1,52 @@
+import { describe, it, expect, vi, beforeEach } from 'vitest';
+import { createApp } from 'vue';
+import App from '../src/App.vue';
+import vuetify from '../src/plugins/vuetify';
+import router from '../src/router';
+
+vi.mock('vue', async () => {
+  const actual = await vi.importActual('vue');
+  return {
+    ...actual,
+    createApp: vi.fn(),
+  };
+});
+
+vi.mock('./assets/main.css', () => ({}));
+
+vi.mock('./plugins/vuetify', () => ({
+  default: {
+    install: vi.fn(),
+  },
+}));
+
+vi.mock('./router', () => ({
+  default: {
+    install: vi.fn(),
+  },
+}));
+
+describe('main.ts', () => {
+  beforeEach(() => {
+    document.body.innerHTML = '<div id="app"></div>';
+    vi.mocked(createApp).mockImplementation(() => ({
+      use: vi.fn(),
+      mount: vi.fn(),
+    }));
+  });
+
+  it('creates app and uses plugins', async () => {
+    await import("../src/main");
+
+    expect(createApp).toHaveBeenCalledTimes(1);
+    expect(createApp).toHaveBeenCalledWith(App);
+
+    const appMock = vi.mocked(createApp).mock.results[0].value;
+    expect(appMock.use).toHaveBeenCalledTimes(2);
+    expect(appMock.use).toHaveBeenCalledWith(vuetify);
+    expect(appMock.use).toHaveBeenCalledWith(router);
+
+    expect(appMock.mount).toHaveBeenCalledTimes(1);
+    expect(appMock.mount).toHaveBeenCalledWith('#app');
+  });
+});