Fix: prevent black screen after failed initialization.

If a crash occurs before feedback is started then attempting to report that crash will, itself, crash because the lateinit feedback instance is not initialized. The result is a black screen on launch! This fixes that by catching everything while trying to report an error.

app/src/main/java/cash/z/ecc/android/ZcashWalletApp.kt

@@ -7,10 +7,8 @@ import androidx.camera.camera2.Camera2Config
 import androidx.camera.core.CameraXConfig
 import cash.z.ecc.android.di.component.AppComponent
 import cash.z.ecc.android.di.component.DaggerAppComponent
+import cash.z.ecc.android.ext.tryWithWarning
 import cash.z.ecc.android.feedback.FeedbackCoordinator
-import cash.z.ecc.android.sdk.ext.SilentTwig
-import cash.z.ecc.android.sdk.ext.TroubleshootingTwig
-import cash.z.ecc.android.sdk.ext.Twig
 import cash.z.ecc.android.sdk.ext.twig
 import kotlinx.coroutines.*
 import javax.inject.Inject
@@ -68,19 +66,34 @@ class ZcashWalletApp : Application(), CameraXConfig.Provider {
      * is complete, we can lazily initialize all the feedback objects at this moment so that we
      * don't have to add any time to startup.
      */
-    inner class ExceptionReporter(private val ogHandler: Thread.UncaughtExceptionHandler) : Thread.UncaughtExceptionHandler {
+    inner class ExceptionReporter(private val ogHandler: Thread.UncaughtExceptionHandler) :
+        Thread.UncaughtExceptionHandler {
         override fun uncaughtException(t: Thread?, e: Throwable?) {
             twig("Uncaught Exception: $e caused by: ${e?.cause}")
-            // these are the only reported crashes that are considered fatal
+            // Things can get pretty crazy during a fatal exception
-            coordinator.feedback.report(e, true)
+            // so be cautious here to avoid freezing the app
-            coordinator.flush()
+            tryWithWarning("Unable to report fatal crash") {
-            // can do this if necessary but first verify that we need it
+                // note: these are the only reported crashes that set isFatal=true
-            runBlocking {
+                coordinator.feedback.report(e, true)
-                coordinator.await()
+            }
-                coordinator.feedback.stop()
+            tryWithWarning("Unable to flush the feedback coordinator") {
+                coordinator.flush()
+            }
+
+            try {
+                // can do this if necessary but first verify that we need it
+                runBlocking {
+                    coordinator.await()
+                    coordinator.feedback.stop()
+                }
+            } catch (t: Throwable) {
+                twig("WARNING: failed to wait for the feedback observers to complete.")
+            } finally {
+                // it's important that this always runs so we use the finally clause here
+                // rather than another tryWithWarning block
+                ogHandler.uncaughtException(t, e)
+                Thread.sleep(2000L)
             }
-            ogHandler.uncaughtException(t, e)
-            Thread.sleep(2000L)
         }
     }
 }

app/src/main/java/cash/z/ecc/android/ext/Extensions.kt

@@ -1,3 +1,14 @@
 package cash.z.ecc.android.ext
 
-fun Boolean.asString(ifTrue: String = "", ifFalse: String = "") = if(this) ifTrue else ifFalse
+import cash.z.ecc.android.sdk.ext.twig
+
+fun Boolean.asString(ifTrue: String = "", ifFalse: String = "") = if(this) ifTrue else ifFalse
+
+inline fun <R> tryWithWarning(message: String = "", block: () -> R): R? {
+    return try {
+        block()
+    } catch (error: Throwable) {
+        twig("WARNING: $message")
+        null
+    }
+}