android - JUnit 5 参数化测试 - 使用 Kotlin 的 @MethodSource 中的 'Cannot invoke non-static method'

Question

预计

将标准 JUnit 5 测试转换为参数化测试，以便使用 @ParamterizedTest 迭代测试用例流。和 @MethodSource Kotlin 中的注释。

观察
@MethodSource无法访问数据流。这似乎是这个注释的一个问题，如 @ValueSource(strings = ["SF", "NYC"])按预期迭代静态定义的选项。

错误:

PreconditionViolationException: Cannot invoke non-static method {someMethodName} on a null target.

实现

参数化测试设置为传入数据类流，类似于 Phillip Hauer 在 Data Classes for Parameterized Tests 中概述的设置。 .

代码

build.gradle (:SomeProject)

dependencies {
    ...    
    classpath("de.mannodermaus.gradle.plugins:android-junit5:$junit5_version")
}

build.gradle (:someModule)

apply plugin: "de.mannodermaus.android-junit5"
android {
    ...
    compileOptions.targetCompatibility = JavaVersion.VERSION_1_8
    kotlinOptions.jvmTarget = "1.8"
}
dependencies {
    testImplementation "org.junit.jupiter:junit-jupiter-api:5.6.2"
    testRuntimeOnly "org.junit.jupiter:junit-jupiter-engine:5.6.2"
    testImplementation "org.junit.jupiter:junit-jupiter-params:5.6.2"
}

SomeTest.kt

class SomeTest {
    private val testDispatcher = TestCoroutineDispatcher()

    private fun someDataStates() = Stream.of(
        // Kotlin data class
        TestState("123"),
        TestState("345")
    )

    @ParameterizedTest
    @MethodSource("someDataStates")
    fun someTest(testState: TestState) = testDispatcher.runBlockingTest {
        // Test state here.
        ...
    }
}

搭建环境

Android Studio 4.0

构建 #AI-193.6911.18.40.6514223，构建于 2020 年 5 月 20 日

运行时版本:1.8.0_242-release-1644-b3-6222593 x86_64

虚拟机:JetBrains s.r.o 的 OpenJDK 64 位服务器虚拟机

macOS 10.15.5

GC:ParNew、ConcurrentMarkSweep

内存:1979M

核心数:16

注册表:ide.new.welcome.screen.force=true

非 bundle 插件:cn.wjdghd.unique.plugin.id、com.android.tool.sizereduction.plugin、com.developerphil.adbidea、com.thoughtworks.gauge、mobi.hsz.idea.gitignore

尝试的解决方案

1. 将测试用例数据状态重构为顶级函数。

测试用例.kt

fun someDataStates() = Stream.of(
    TestState("123"),
    TestState("345")
)

SomeTest.kt

private fun SomeDataStates() = someDataStates()

@ParameterizedTest
@MethodSource("SomeDataStates")
fun someTest(testState: TestState) = testDispatcher.runBlockingTest {
   // Test state here.
   ...

}

2. 将测试用例数据状态重构为 List 类型的顶级函数而不是 Stream .

fun someDataStates() = listOf(
    TestState("123"),
    TestState("345")
)

完整的错误日志

org.junit.platform.commons.PreconditionViolationException: Cannot invoke non-static method [private final {someMethodName} on a null target.

at org.junit.platform.commons.util.Preconditions.condition(Preconditions.java:296) at org.junit.platform.commons.util.ReflectionUtils.invokeMethod(ReflectionUtils.java:682) at org.junit.jupiter.params.provider.MethodArgumentsProvider.lambda$provideArguments$1(MethodArgumentsProvider.java:46) at java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:193) at java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:193) at java.util.Spliterators$ArraySpliterator.forEachRemaining(Spliterators.java:948) at java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:482) at java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:472) at java.util.stream.ForEachOps$ForEachOp.evaluateSequential(ForEachOps.java:150) at java.util.stream.ForEachOps$ForEachOp$OfRef.evaluateSequential(ForEachOps.java:173) at java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234) at java.util.stream.ReferencePipeline.forEach(ReferencePipeline.java:485) at java.util.stream.ReferencePipeline$7$1.accept(ReferencePipeline.java:272) at java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:193) at java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:193) at java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:193) at java.util.ArrayList$ArrayListSpliterator.forEachRemaining(ArrayList.java:1382) at java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:482) at java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:472) at java.util.stream.ForEachOps$ForEachOp.evaluateSequential(ForEachOps.java:150) at java.util.stream.ForEachOps$ForEachOp$OfRef.evaluateSequential(ForEachOps.java:173) at java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234) at java.util.stream.ReferencePipeline.forEach(ReferencePipeline.java:485) at java.util.stream.ReferencePipeline$7$1.accept(ReferencePipeline.java:272) at java.util.ArrayList$ArrayListSpliterator.forEachRemaining(ArrayList.java:1382) at java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:482) at java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:472) at java.util.stream.ForEachOps$ForEachOp.evaluateSequential(ForEachOps.java:150) at java.util.stream.ForEachOps$ForEachOp$OfRef.evaluateSequential(ForEachOps.java:173) at java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234) at java.util.stream.ReferencePipeline.forEach(ReferencePipeline.java:485) at org.junit.jupiter.engine.descriptor.TestTemplateTestDescriptor.execute(TestTemplateTestDescriptor.java:106) at org.junit.jupiter.engine.descriptor.TestTemplateTestDescriptor.execute(TestTemplateTestDescriptor.java:41) at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$5(NodeTestTask.java:135) at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73) at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$7(NodeTestTask.java:125) at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:135) at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:123) at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73) at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:122) at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:80) at java.util.ArrayList.forEach(ArrayList.java:1257) at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.invokeAll(SameThreadHierarchicalTestExecutorService.java:38) at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$5(NodeTestTask.java:139) at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73) at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$7(NodeTestTask.java:125) at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:135) at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:123) at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73) at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:122) at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:80) at java.util.ArrayList.forEach(ArrayList.java:1257) at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.invokeAll(SameThreadHierarchicalTestExecutorService.java:38) at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$5(NodeTestTask.java:139) at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73) at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$7(NodeTestTask.java:125) at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:135) at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:123) at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73) at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:122) at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:80) at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.submit(SameThreadHierarchicalTestExecutorService.java:32) at org.junit.platform.engine.support.hierarchical.HierarchicalTestExecutor.execute(HierarchicalTestExecutor.java:57) at org.junit.platform.engine.support.hierarchical.HierarchicalTestEngine.execute(HierarchicalTestEngine.java:51) at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:248) at org.junit.platform.launcher.core.DefaultLauncher.lambda$execute$5(DefaultLauncher.java:211) at org.junit.platform.launcher.core.DefaultLauncher.withInterceptedStreams(DefaultLauncher.java:226) at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:199) at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:132) at com.intellij.junit5.JUnit5IdeaTestRunner.startRunnerWithArgs(JUnit5IdeaTestRunner.java:69) at com.intellij.rt.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:33) at com.intellij.rt.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:230) at com.intellij.rt.junit.JUnitStarter.main(JUnitStarter.java:58) Suppressed: org.junit.platform.commons.PreconditionViolationException: Configuration error: You must configure at least one set of arguments for this @ParameterizedTest at org.junit.platform.commons.util.Preconditions.condition(Preconditions.java:281) at org.junit.jupiter.params.ParameterizedTestExtension.lambda$provideTestTemplateInvocationContexts$6(ParameterizedTestExtension.java:90) at java.util.stream.AbstractPipeline.close(AbstractPipeline.java:323) at java.util.stream.ReferencePipeline$7$1.accept(ReferencePipeline.java:279) ... 49 more

Process finished with exit code 255

Answer 1

我猜你错过了告诉 JUnit 实例化你的测试类一次的信息，如下所示:

import org.junit.jupiter.api.TestInstance
import org.junit.jupiter.api.TestInstance.Lifecycle.PER_CLASS

@TestInstance(PER_CLASS) // <--- This one will do the trick
class SomeTest {

    private val testDispatcher = TestCoroutineDispatcher()

    @ParameterizedTest
    @MethodSource("someDataStates")
    fun someTest(testState: TestState) = testDispatcher.runBlockingTest {
        // Test state here.
        ...
    }

    private fun someDataStates() = listOf(
        TestState("123"),
        TestState("345")
    )
}