Crash during espresso tests

[emartynov]

We have a crash:

05-06 11:09:32.164 | error | AndroidRuntime | FATAL EXCEPTION: IntentService[leakcanary.internal.AnalysisResultService]
-- | -- | -- | --
05-06 11:09:32.164 | error | AndroidRuntime | Process: com.yolt.mobile.aws, PID: 4762
05-06 11:09:32.164 | error | AndroidRuntime | java.util.NoSuchElementException: List is empty.
05-06 11:09:32.164 | error | AndroidRuntime | at kotlin.collections.CollectionsKt___CollectionsKt.first(_Collections.kt:194)
05-06 11:09:32.164 | error | AndroidRuntime | at leakcanary.internal.activity.db.LeakingInstanceTable.createGroupDescription(LeakingInstanceTable.kt:262)
05-06 11:09:32.164 | error | AndroidRuntime | at leakcanary.internal.activity.db.LeakingInstanceTable.insert(LeakingInstanceTable.kt:44)
05-06 11:09:32.164 | error | AndroidRuntime | at leakcanary.internal.activity.db.HeapAnalysisTable.insert(HeapAnalysisTable.kt:53)
05-06 11:09:32.164 | error | AndroidRuntime | at leakcanary.internal.AnalysisResultService.onHeapAnalyzed(AnalysisResultService.kt:91)
05-06 11:09:32.164 | error | AndroidRuntime | at leakcanary.internal.AnalysisResultService.onHandleIntentInForeground(AnalysisResultService.kt:70)
05-06 11:09:32.164 | error | AndroidRuntime | at leakcanary.internal.ForegroundService.onHandleIntent(ForegroundService.kt:56)
05-06 11:09:32.164 | error | AndroidRuntime | at android.app.IntentService$ServiceHandler.handleMessage(IntentService.java:68)
05-06 11:09:32.164 | error | AndroidRuntime | at android.os.Handler.dispatchMessage(Handler.java:102)
05-06 11:09:32.164 | error | AndroidRuntime | at android.os.Looper.loop(Looper.java:154)
05-06 11:09:32.164 | error | AndroidRuntime | at android.os.HandlerThread.run(HandlerThread.java:61)

It happened during our automated tests and I see from the log that LeakCanary detected a leak.

[emartynov]

We are using the 2.0-alpha1 version.

[pyricau]

Any chance you have a heap dump that could help me reproduce this?

This is happening because LeakCanary found 0 potential leak cause, which likely means the entire leak trace is considered reachable or unreachable, or there are inconsistencies. This is usually due to reachability inspectors reaching conflicting conclusions. I've added rules for alpha-2 that will correctl detect and solve conflicts, which means this shouldn't happen in the next release.

That being said I'd love to know what the inspectors are getting wrong, a heap dump would help

[emartynov]

I have a log of the leak, I don't have a dump. I can try to add saving of the dump, let me find how to do it.

[pyricau]

One thing that's surprising to me: are you not using the instrumentation test listener? It looks like you're running normal LeakCanary in tests instead, which means the tests might be randomly freezing on heap dumps.

[emartynov]

Good comment - I didn't add no-op dependency to instrumental tests. That is why "normal" LeakCanary also operates while running the UI tests. Let me do it and see what happens.

[pyricau]

no-op is gone. Try this: https://proandroiddev.com/detecting-memory-leaks-in-your-instrumentation-tests-using-leakcanary-1268e911d5ce

[pyricau]

Added a recipe here: https://github.com/square/leakcanary/blob/master/README.md#running-leakcanary-in-instrumentation-tests

[emartynov]

Oh wait, you're right and I actually have this already.

[emartynov]

Then I don't know what could be the issue.

[pyricau]

The crash shows that AnalysisResultService was started. AnalysisResultService should not start when FailTestOnLeakRunListener is set up: FailTestOnLeakRunListener#testRunStarted calls InstrumentationLeakDetector.Companion#updateConfig which configures LeakCanary to not dump the heap. Unless you're overriding that configuration somewhere else in the code?

[emartynov]

Yes, we do, on the app start:

    fun install() {
        LeakCanary.config =
                LeakCanary.config.copy(excludedRefs = excludeSamsung(AndroidExcludedRefs.createAppDefaults()).build())
    }

    /**
     * LeakCanary is only excluding the SemClipboardManager and SemEmergencyManager until Android API 24,
     * but still occurs on Android API 25.
     */
    private fun excludeSamsung(builder: ExcludedRefs.Builder): ExcludedRefs.Builder {
        if ("samsung" == Build.MANUFACTURER && SDK_INT <= N_MR1) {
            builder.instanceField("com.samsung.android.content.clipboard.SemClipboardManager", "mContext")
                    .reason(
                            "SemClipboardManager is held in memory by an anonymous inner class implementation of " +
                                    "android.os.Binder, thereby leaking an activity context."
                    )
                    .instanceField("com.samsung.android.emergencymode.SemEmergencyManager", "mContext")
                    .reason("SemEmergencyManager is a static singleton that leaks a DecorContext.")
        }
        return builder
    }

[emartynov]

But this also means that if I remove the listener from UI test I have somehow suppress LeakCanary from running in the UI tests since there is no-op. Let me add in our test runner config modification as well.

[ber4444]

I also have CI builds randomly fail because of leak canary (latest alpha) breaking Espresso tests. E.g.

java.util.NoSuchElementException: List is empty.
FATAL EXCEPTION: IntentService[leakcanary.internal.AnalysisResultService]
Process: com.blah.activities.debug, PID: 7940
java.util.NoSuchElementException: List is empty.
	at kotlin.collections.CollectionsKt___CollectionsKt.first(_Collections.kt:194)
	at leakcanary.internal.activity.db.LeakingInstanceTable.createGroupDescription(LeakingInstanceTable.kt:262)
	at leakcanary.internal.activity.db.LeakingInstanceTable.insert(LeakingInstanceTable.kt:44)
	at leakcanary.internal.activity.db.HeapAnalysisTable.insert(HeapAnalysisTable.kt:53)
	at leakcanary.internal.AnalysisResultService.onHeapAnalyzed(AnalysisResultService.kt:91)
	at leakcanary.internal.AnalysisResultService.onHandleIntentInForeground(AnalysisResultService.kt:70)
	at leakcanary.internal.ForegroundService.onHandleIntent(ForegroundService.kt:56)
	at android.app.IntentService$ServiceHandler.handleMessage(IntentService.java:76)
	at android.os.Handler.dispatchMessage(Handler.java:106)
	at android.os.Looper.loop(Looper.java:193)
	at android.os.HandlerThread.run(HandlerThread.java:65)

Is there a way I could disable leak canary 2.x for tests now that no-op is gone?

[emartynov]

If you have own test runner then you can try next code:

    override fun onStart() {
        // disable LeakCanary in UI tests here since we don't have no-op artifact anymore
        LeakCanary.config = LeakCanary.config.copy(dumpHeap = false, computeRetainedHeapSize = false)

        // carry on
        super.onStart()
    }

[ber4444]

Sorry, where should I put this code? You wrote a custom AndroidJUnitRunner?

[emartynov]

Sound like you don't have it.

Then you should add new class to espresso test:

class <My>InstrumentationRunner : AndroidJUnitRunner() 

Then you should also define it in your build.gradle:

android {
  ...
  defaultConfig {
    ...
    testInstrumentationRunner 'com.<yourpackge>.<My>InstrumentationRunner'
  }
}

And then, in this runner, you should override onStart method.

[pyricau]

This should be fixed in the next release, let me know if not.