kotlin - 如何通过interceptTestCase更改KotlinTest中的测试对象属性

Question

我正在尝试使用interceptTestCase方法为KotlinTest中的测试用例设置属性，如下所示:

class MyTest : ShouldSpec() {
    private val items = mutableListOf<String>()
    private var thing = 123

    override fun interceptTestCase(context: TestCaseContext, test: () -> Unit) {
        items.add("foo")
        thing = 456
        println("Before test ${items.size} and ${thing}")
        test()
        println("After test ${items.size} and ${thing}")
    }

    init {
        should("not work like this") {
            println("During test ${items.size} and ${thing}")
        }
    }
}

我得到的输出是:

Before test 1 and 456

During test 0 and 123

After test 1 and 456

所以我所做的更改在测试用例中是不可见的。我应该如何在执行每个测试之前更改属性？

Answer 1

您应该通过 TestCaseContext 访问当前规范。每个测试都有单独的 Spec ，例如:

override fun interceptTestCase(context: TestCaseContext, test: () -> Unit) {
    //                v--- casting down to the special Spec here.
    with(context.spec as MyTest) {
    //^--- using with function to take the `receiver` in lambda body

        items.add("foo") // --
                         //   |<--- update the context.spec properties
        thing = 456      // --

        println("Before test ${items.size} and ${thing}")
        test()
        println("After test ${items.size} and ${thing}")
    }
}