✨ [Feature]: Components of tiny-vue may need to add unit tests

### What problem does this feature solve

增加单元测试，有利提高代码质量，简化代码重构。

建议优先完善高频组件的 TypeScript 类型声明。

[TinyVue 高频组件](https://github.com/opentiny/tiny-vue/wiki/TinyVue-%E9%AB%98%E9%A2%91%E7%BB%84%E4%BB%B6%E5%88%97%E8%A1%A8)

### What does the proposed API look like

增加单元测试。