TypeError：无法读取 null 的属性“类型” - 使用异步函数测试 vue 组件
P粉818306280
2023-08-28 23:34:29
<p>我正在测试组件 ComponentA.spec.js，但收到 <code>TypeError: Cannot read property 'type' of null</code>。如果我去掉 ComponentA 中 getData() 函数中的 wait 关键字，它就会起作用。我在测试中模拟了 getData api 调用，但它仍然不起作用。</p>
<p>这是完整的堆栈
类型错误：C：[隐私]\未知：无法读取 null 的属性“类型”</p>
<pre class="brush:js;toolbar:false;">at assert (node_modules/@babel/types/lib/asserts/generated/index.js:284:112)
at Object.assertIdentifier (node_modules/@babel/types/lib/asserts/generated/index.js:373:3)
at new CatchEntry (node_modules/regenerator-transform/lib/leap.js:93:5)
at Emitter.Ep.explodeStatement (node_modules/regenerator-transform/lib/emit.js:535:36)
at node_modules/regenerator-transform/lib/emit.js:323:12
at Array.forEach (<anonymous>)
at Emitter.Ep.explodeStatement (node_modules/regenerator-transform/lib/emit.js:322:22)
at Emitter.Ep.explode (node_modules/regenerator-transform/lib/emit.js:280:40)
</pre>
<p>这是我正在尝试为其创建测试的组件 A</p>
<pre class="brush:js;toolbar:false;"><template>
<div class="d-flex flex-row">
<component-b />
<component-c />
</div>
</template>
<script>
import ComponentB from './ComponentB';
import ComponentC from './ComponentC';
import { getData } from 'apis';
export default {
name: 'component-a',
components: {
ComponentB,
ComponentC,
},
async created() {
await this.getData();
},
methods: {
// This function is the culprit
async getData() {
try {
const response = await getData();
} catch {
//
}
},
},
};
</script>
</pre>
<p>这是我的 ComponentA.spec.js 文件</p>
<pre class="brush:js;toolbar:false;">import Vuetify from 'vuetify';
import ComponentA from 'components/ComponentA';
import { createLocalVue, shallowMount, mount } from '@vue/test-utils';
jest.mock('shared/apis', () => {
const data = require('../fixedData/data.json');
return {
getData: jest.fn().mockResolvedValue(data),
};
});
const localVue = createLocalVue();
let vuetify;
function createShallowWrapper(options = {}) {
return shallowMount(ComponentA, {
localVue,
vuetify,
...options,
});
}
beforeEach(() => {
vuetify = new Vuetify();
});
describe('ComponentA', () => {
describe('component creation', () => {
test('testing', () => {
const wrapper = createShallowWrapper();
expect(wrapper).toMatchSnapshot();
});
});
});
</pre></p>
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将异常变量 (e) 添加到 ComponentA 中 getData 函数中的捕获中修复了该问题。