test: add tests for useShallowRef

src/__tests__/advanced.test.tsx

@@ -0,0 +1,35 @@
+import '@testing-library/jest-dom';
+import { isRef, useShallowRef } from '..';
+import 'jest-performance-testing';
+import { renderHook } from '@testing-library/react';
+import { isShallow } from '@vue/reactivity';
+
+describe('useShallowRef', () => {
+  it('returns a valid ref', () => {
+    const { result } = renderHook(() => useShallowRef(1));
+    expect(result.current.value).toBe(1);
+    expect(isRef(result.current)).toBe(true);
+    expect(isShallow(result.current)).toBe(true);
+  });
+  it('keeps the same instance across re-render', () => {
+    const { result, rerender } = renderHook(() => useShallowRef(1));
+    const ref = result.current;
+
+    rerender();
+
+    expect(result.current).toBe(ref);
+  });
+  it('works with initializer function', () => {
+    const initializer = jest.fn(() => ({ count: 1 }));
+    const { result, rerender } = renderHook(() => useShallowRef(initializer));
+    const ref = result.current;
+    expect(result.current.value.count).toBe(1);
+    expect(initializer).toBeCalledTimes(1);
+
+    rerender();
+
+    expect(result.current.value.count).toBe(1);
+    expect(initializer).toBeCalledTimes(1);
+    expect(result.current).toBe(ref);
+  });
+});