AndroidReferenceReadersHprofTest.kt

TLDR

The AndroidReferenceReadersHprofTest.kt file contains test cases for checking references and leaks in a heap dump file (hprof file). It also includes helper functions for loading files and checking for leaks.

Classes

AndroidReferenceReadersHprofTest

This class contains test methods for checking references and leaks in a heap dump file. The file is loaded and analyzed using the checkForLeaks function from the Shark library. Different assertions are made on the references found in the leak traces.

Helper functions

• File.checkForFakeArraySetLeak(): This function is an extension function on the File class. It checks for a specific fake leak in the heap graph using the Shark library. It creates a custom LeakingObjectFinder implementation and uses it in the checkForLeaks function.
• String.classpathFile(): This function is an extension function on the String class. It converts a classpath string to a File object.

package shark.internal

import java.io.File
import org.assertj.core.api.Assertions.assertThat
import org.junit.Test
import shark.HeapAnalysisSuccess
import shark.HeapGraph
import shark.IgnoredReferenceMatcher
import shark.LeakTraceReference.ReferenceType.ARRAY_ENTRY
import shark.LeakingObjectFinder
import shark.ReferencePattern.StaticFieldPattern
import shark.checkForLeaks
import shark.defaultReferenceMatchers

class AndroidReferenceReadersHprofTest {

  @Test fun `safe iterable map traversed as dictionary`() {
    val hprofFile = "safe_iterable_map.hprof".classpathFile()
    val analysis = hprofFile.checkForLeaks<HeapAnalysisSuccess>()
    val leakTrace = analysis.applicationLeaks.single().leakTraces.single()

    val mapReference =
      leakTrace.referencePath.single { it.owningClassSimpleName == "FastSafeIterableMap" }
    assertThat(mapReference.referenceName).isEqualTo("key()")
    assertThat(mapReference.referenceType).isEqualTo(ARRAY_ENTRY)
  }

  @Test fun `API 25 HashMap$HashMapEntry supported`() {
    val hprofFile = "hashmap_api_25.hprof".classpathFile()
    val analysis = hprofFile.checkForLeaks<HeapAnalysisSuccess>()
    val leakTrace = analysis.applicationLeaks.single().leakTraces.single()

    val mapReference =
      leakTrace.referencePath.single { it.owningClassSimpleName == "HashMap" }
    assertThat(mapReference.referenceName).isEqualTo("\"leaking\"")
    assertThat(mapReference.referenceType).isEqualTo(ARRAY_ENTRY)
  }

  @Test fun `ArraySet traversed as set`() {
    // This hprof happens to have an ArraySet in it.
    val hprofFile = "safe_iterable_map.hprof".classpathFile()

    val analysis = hprofFile.checkForFakeArraySetLeak()

    val leakTrace = analysis.applicationLeaks.single().leakTraces.single()

    println(leakTrace)

    val mapReference =
      leakTrace.referencePath.single { it.owningClassSimpleName == "ArraySet" }
    assertThat(mapReference.referenceName).isEqualTo("element()")
    assertThat(mapReference.referenceType).isEqualTo(ARRAY_ENTRY)
  }
}

fun File.checkForFakeArraySetLeak(): HeapAnalysisSuccess {
  val instanceHeldByArraySet =
    "android.view.accessibility.AccessibilityNodeInfo\$AccessibilityAction"

  class ArraySetFakeLeakingObjectFinder : LeakingObjectFinder {
    override fun findLeakingObjectIds(graph: HeapGraph): Set<Long> {
      val arraySetInstances = graph.findClassByName("android.util.ArraySet")!!
        .instances
        .map { arraySetInstance ->
          arraySetInstance to arraySetInstance["android.util.ArraySet", "mArray"]!!
            .valueAsObjectArray!!
            .readElements()
            .filter {
              it.asObject?.asInstance?.instanceClass?.name == instanceHeldByArraySet
            }
            .toList()
        }
      val firstElementReferencedByArraySet = arraySetInstances.first { (_, elements) ->
        elements.isNotEmpty()
      }.second.first()

      return setOf(firstElementReferencedByArraySet.asObjectId!!)
    }
  }
  return checkForLeaks(
    referenceMatchers = defaultReferenceMatchers + IgnoredReferenceMatcher(
      StaticFieldPattern(
        instanceHeldByArraySet,
        "ACTION_FOCUS"
      )
    ),
    leakingObjectFinder = ArraySetFakeLeakingObjectFinder()
  )
}

fun String.classpathFile(): File {
  val classLoader = Thread.currentThread()
    .contextClassLoader
  val url = classLoader.getResource(this)!!
  return File(url.path)
}