java - 使用JUnit运行时，Intellij IDEA不会在Kotlin断点处停止

Question

当尝试执行一些Kotlin代码时，同时也使用JUnit，Intellij IDEA将执行代码直到结束，而不是在断点处停止。

演示:

class Tester {

    @Test
    fun shouldBreakpoint() {
        //Line where threads should suspend:
        println("Should Suspend Here") //Breakpoint added to this line

        println("Shouldn't run this code unless I release above breakpoint")

    }
}

单击“调试测试器”或“调试应该断开点”时，将不会有任何断点。


控制台输出两条打印线，而不会在断点处停止。如果使用Java编写相同的代码，则调试器将工作:

public class Testerino {

    @Test
    public void shouldBreakpoint() {

        System.out.println("Should Suspend Here"); //Breakpoint added to this line

        System.out.println("Shouldn't run this code unless I release above breakpoint");
    }
}

在Kotlin main函数上运行时，它也可以正常运行:

fun main(args: Array<String>) {
println("Should Suspend Here") //Breakpoint added to this line

println("Shouldn't run this code unless I release above breakpoint")

}

这是在Android项目上运行，并且build.gradle(应用程序)文件为:

   apply plugin: 'com.android.application'
apply plugin: 'kotlin-android'

android {
    compileSdkVersion 27
    buildToolsVersion "27.0.3"
    defaultConfig {
        applicationId "me.kerooker.visualhonk"
        minSdkVersion 19
        targetSdkVersion 27
        versionCode 1
        versionName "1.0"
        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
         vectorDrawables.useSupportLibrary = true

    }
    buildTypes {
        release {
            minifyEnabled false
            shrinkResources false
            proguardFiles getDefaultProguardFile('proguard-android.txt')
        }
        debug {
            debuggable true
            minifyEnabled false // set this to false
            proguardFiles getDefaultProguardFile('proguard-android.txt')
        }
    }
}

configurations.all {
    resolutionStrategy {
        forcedModules = [
                "org.jetbrains.kotlin:kotlin-stdlib:$kotlin_version",
                "org.jetbrains.kotlin:kotlin-reflect:$kotlin_version"
        ]
    }
}

dependencies {
    compile fileTree(dir: 'libs', include: ['*.jar'])
    androidTestCompile('com.android.support.test.espresso:espresso-core:2.2.2', {
        exclude group: 'com.android.support', module: 'support-annotations'
    })
    compile 'com.android.support:appcompat-v7:27.+'
    compile 'com.android.support.constraint:constraint-layout:+'
    compile "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"

    testCompile 'io.kotlintest:kotlintest:2.0.7'
    testCompile 'junit:junit:4.12'


}
repositories {
    mavenCentral()
}

如何使Intellij正确识别并在断点处停止？

Answer 1

自this commit起，此错误似乎已修复。更新Intellij以获取新版本。

如果您无法更新，则解决方法是从运行过程中删除可识别gradle的make ，并且仅在进行更改时构建代码(而不是每次启动调试时都构建)

解决方法:

Hitting breakpoints in Kotlin JUnit test with an Android Gradle
project sometimes(*) does not work in Android Studio 3.1 beta.

(*) The issue is related to various threads running concurrently
with "dumb" mode background code, so the issue reproduces only
on certain configurations.

In a nutshell, the issue is as follows

* On one hand, gradle build finishes, fires an event ("buildFinished")
  that is processed "later" and that causes the IDE to enter "dumb" mode
  for a shot amount of time (about 300-500 msec on a somewhat up to date
  multi-core computer).

* On the other hand, once the JVM of the debuggee is started, breakpoints
  need to be resolved (on the debugger thread, through a call to
  com.intellij.debugger.engine.CompoundPositionManager.createPrepareRequests.
  This code calls into the "KotlinPositionManager.createPrepareRequests",
  which in turns calls into "PerFileAnalysisCache.analyze". That method
  returns "AnalysisResult.EMPTY" is the project is in dumb mode.
  This return value prevents callers from successfully resolving
  the source location into a breakpoint.

Given that the 2 code paths above execute on separate threads without
explicit synchronization, the "failed to resolve breakpoint" issue
occurs sporadically, to the point it happens 100% of the time on
certain configuration.

The fix is so wrap the kotlin breakpoint resolution code inside
a "runReadActionInSmartMode" so that the debugger thread "waits"
for "dumb" mode to terminates before trying to resolve breakpoint
locations.