LabelerTest.kt

TLDR

This file contains the LabelerTest class, which is a test class for the Labeler class in the shark package. It includes three test methods: stringContentAsLabel, labelOnUnreachableObject, and threadNameLabel. These methods test different functionalities of the Labeler class.

Methods

stringContentAsLabel

This test method checks if the Labeler class correctly labels a leaking object in a heap analysis. It writes a string path to a temporary HPROF file, creates an ObjectInspector with a specific label for instances of the java.lang.String class, performs a heap analysis on the HPROF file using the labeler object inspector, and asserts that the leaking object in the heap analysis results has the expected label.

labelOnUnreachableObject

This test method checks if the Labeler class correctly labels an unreachable object in a heap dump. It creates a heap dump with an instance of the com.example.SomeClass class, creates an ObjectInspector with a label based on the class name of instances of java.lang.Object, performs a heap analysis on the heap dump using the labeler object inspector, and asserts that the unreachable object in the heap analysis results has the expected label.

threadNameLabel

This test method checks if the Labeler class correctly labels a thread object in a heap analysis. It writes a Java local leak with a specified thread class and thread name to a temporary HPROF file, performs a heap analysis on the HPROF file using the ObjectInspectors.THREAD object inspector, and asserts that the origin object (first object in the leak trace) in the heap analysis results has the expected label.

Classes

LabelerTest

This test class is used to test the functionality of the Labeler class. It includes three test methods: stringContentAsLabel, labelOnUnreachableObject, and threadNameLabel. These methods test different functionalities of the Labeler class by performing heap analysis and asserting the expected labels.

package shark

import org.assertj.core.api.Assertions.assertThat
import org.junit.Before
import org.junit.Rule
import org.junit.Test
import org.junit.rules.TemporaryFolder
import java.io.File

class LabelerTest {

  @get:Rule
  var testFolder = TemporaryFolder()
  private lateinit var hprofFile: File

  @Before
  fun setUp() {
    hprofFile = testFolder.newFile("temp.hprof")
  }

  @Test fun stringContentAsLabel() {
    hprofFile.writeSinglePathToString("World")

    val labeler = ObjectInspector { reporter ->
      reporter.whenInstanceOf("java.lang.String") { instance ->
        labels += "Hello ${instance.readAsJavaString()}"
      }
    }

    val analysis = hprofFile.checkForLeaks<HeapAnalysisSuccess>(objectInspectors = listOf(labeler))

    val leakTrace = analysis.applicationLeaks[0].leakTraces.first()

    assertThat(leakTrace.leakingObject.labels).contains("Hello World")
  }

  @Test fun labelOnUnreachableObject() {
    val heapDump = dump {
      "com.example.SomeClass" watchedInstance {
      }
    }

    val labeler = ObjectInspector { reporter ->
      reporter.whenInstanceOf("java.lang.Object") { instance ->
        labels += instance.instanceClassSimpleName
      }
    }

    val analysis = heapDump.checkForLeaks<HeapAnalysisSuccess>(objectInspectors = listOf(labeler))

    assertThat(analysis.unreachableObjects[0].labels).contains("SomeClass")
  }

  @Test fun threadNameLabel() {
    hprofFile.writeJavaLocalLeak(threadClass = "MyThread", threadName = "kroutine")

    val analysis =
      hprofFile.checkForLeaks<HeapAnalysisSuccess>(
        objectInspectors = listOf(ObjectInspectors.THREAD)
      )

    val leak = analysis.applicationLeaks[0]

    assertThat(leak.leakTraces.first().referencePath.first().originObject.labels).contains(
      "Thread name: 'kroutine'"
    )
  }
}