UncaughtExceptionHandlerIntegration not working correctly when registered against multiple IHub/Scopes

[armatys]

Integration

sentry

Java Version

17

Version

8.12.0

Steps to Reproduce

The fix for #3266 introduced a change in behaviour.

In our app, we actually have two independent Sentry instances. One is initialized as usual, by global Sentry[Android].init, and the other is initialized manually in the library code.

The fix in #3398 seems to assume that there's only one Sentry instance. However, I think that the following test should work fine (which it's currently not):

class UncaughtExceptionHandlerIntegrationTest {
    // ...
    val scopes2 = mock<IScopes>()

    // test analogous to existing one (`multiple registrations do not cause the build-up of a tree of UncaughtExceptionHandlerIntegrations`):
    @Test
    fun `multiple registrations`() {
        val initialUncaughtExceptionHandler = Thread.UncaughtExceptionHandler { _, _ -> }

        var currentDefaultHandler: Thread.UncaughtExceptionHandler? = initialUncaughtExceptionHandler

        val handler = mock<UncaughtExceptionHandler>()
        whenever(handler.defaultUncaughtExceptionHandler).thenAnswer { currentDefaultHandler }

        whenever(handler.setDefaultUncaughtExceptionHandler(anyOrNull<Thread.UncaughtExceptionHandler>())).then {
            currentDefaultHandler = it.getArgument(0)
            null
        }

        val integration1 = UncaughtExceptionHandlerIntegration(handler)
        integration1.register(fixture.scopes, fixture.options)

        val integration2 = UncaughtExceptionHandlerIntegration(handler)
        integration2.register(fixture.scopes2, fixture.options)

        assertEquals(currentDefaultHandler, integration2)
        integration2.close()

        assertEquals(integration1, currentDefaultHandler)
    }
}

Expected Result

I.e. if I register two independent UncaughtExceptionHandlerIntegration, while using two different IScopes, both the handlers should form a linked list and remain active.

Actual Result

Only one handler (the last one) is active and when it's closed, it's reverted back to the original one.

[stefanosiano]

hi @armatys Thanks for the feedback! Multiple SDK instances running at the same time is not something we actively support. However, we can think about a solution that don't cause the same issue as before, while making it work for this case.

[lbloder]

Hi @armatys, Here's a quick update from our side. We should have a PR up today, which will allow one UncaughtExceptionHandlerIntegration to be registered per GlobalScope. With this change having a second Sentry instance will work as per the documentation here: https://docs.sentry.io/platforms/android/configuration/shared-environments/

I hope this solution works for you