December 2017
Intermediate to advanced
329 pages
6h 9m
Chinese
Content preview from React学习手册
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260
｜
第
10
章
图
10
-
4
：通过测试onRemove属性提高了代码覆盖率
看上去第
8
行代码还没有被覆盖。这是因为我们从来没有使用一个空的颜色数组来渲
染
ColorList
组件。让我们用一个测试用例对第
8
行代码进行覆盖：
describe("Rendering UI", () => {
it("Defaults properties correctly", () =>
expect(shallow(<ColorList />).find('p').text())
.toBe('No Colors Listed. (Add a Color)')
)
})
不提供任何属性的情况下渲染
Color
组件不仅会覆盖第
8
行代码，它还会覆盖设置默认
属性值的第一行代码（见图
10-5
）。
测试
ColorList
组件的代码覆盖率已经非常接近
100%
了。我们唯一没有测试的部分是
onRate
和
onRemove
的默认函数。如果我们不提供这些函数，这些属性将会是必需的。
我们可以通过不提供属性渲染
ColorList
组件来对测试进行改进。我们还希望在第一
个评分按钮和最后一个移除按钮上模拟单击事件：
测试
｜
261
图
10
-
5
：通过测试空的颜色值提高了的代码覆盖率
describe("Rendering ...
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