Prevent crashes in form filling when restoring process

androidshared/src/main/java/org/odk/collect/androidshared/system/ProcessRestoreDetector.kt

@@ -0,0 +1,28 @@
+package org.odk.collect.androidshared.system
+
+import android.content.Context
+import android.os.Bundle
+import org.odk.collect.androidshared.data.getState
+import org.odk.collect.shared.strings.UUIDGenerator
+
+object ProcessRestoreDetector {
+
+    @JvmStatic
+    fun registerOnSaveInstanceState(context: Context, outState: Bundle) {
+        val uuid = UUIDGenerator().generateUUID()
+        context.getState().set("${getKey()}:$uuid", Any())
+        outState.putString(getKey(), uuid)
+    }
+
+    @JvmStatic
+    fun isProcessRestoring(context: Context, savedInstanceState: Bundle?): Boolean {
+        return if (savedInstanceState != null) {
+            val bundleUuid = savedInstanceState.getString(getKey())
+            context.getState().get<Any>("${getKey()}:$bundleUuid") == null
+        } else {
+            false
+        }
+    }
+
+    private fun getKey() = this::class.qualifiedName
+}

androidshared/src/main/java/org/odk/collect/androidshared/system/SavedInstanceStateProvider.kt

@@ -0,0 +1,7 @@
+package org.odk.collect.androidshared.system
+
+import android.os.Bundle
+
+interface SavedInstanceStateProvider {
+    fun getState(savedInstanceState: Bundle?): Bundle?
+}

androidtest/src/main/java/org/odk/collect/androidtest/ActivityScenarioExtensions.kt

@@ -1,6 +1,8 @@
 package org.odk.collect.androidtest
 
 import android.app.Activity
+import android.os.Bundle
+import android.os.PersistableBundle
 import androidx.test.core.app.ActivityScenario
 
 object ActivityScenarioExtensions {
@@ -20,4 +22,10 @@ object ActivityScenarioExtensions {
 
             return isFinishing
         }
+
+    fun <T : Activity> ActivityScenario<T>.saveInstanceState(): Bundle {
+        val bundle = Bundle()
+        onActivity { it.onSaveInstanceState(bundle, PersistableBundle()) }
+        return bundle
+    }
 }

collect_app/src/androidTest/java/org/odk/collect/android/feature/formentry/ProcessRestoreTest.kt

@@ -0,0 +1,64 @@
+package org.odk.collect.android.feature.formentry
+
+import androidx.test.ext.junit.runners.AndroidJUnit4
+import org.junit.Rule
+import org.junit.Test
+import org.junit.rules.RuleChain
+import org.junit.runner.RunWith
+import org.odk.collect.android.R
+import org.odk.collect.android.support.CollectHelpers
+import org.odk.collect.android.support.pages.FormEntryPage
+import org.odk.collect.android.support.pages.FormHierarchyPage
+import org.odk.collect.android.support.pages.Page
+import org.odk.collect.android.support.rules.FormEntryActivityTestRule
+import org.odk.collect.android.support.rules.TestRuleChain
+
+@RunWith(AndroidJUnit4::class)
+class ProcessRestoreTest {
+
+    private val rule = FormEntryActivityTestRule()
+
+    @get:Rule
+    val ruleChain: RuleChain = TestRuleChain.chain().around(rule)
+
+    @Test
+    fun whenProcessIsKilledAndRestoredDuringFormEntry_returnsToHierarchy() {
+        rule.setUpProjectAndCopyForm("one-question.xml")
+            .fillNewForm("one-question.xml", "One Question")
+            .answerQuestion("what is your age", "123")
+            .let { simulateProcessRestore(FormHierarchyPage("One Question")) }
+
+            .assertText("123")
+            .pressBack(FormEntryPage("One Question"))
+            .assertQuestion("what is your age")
+    }
+
+    @Test
+    fun whenProcessIsKilledAndRestoredDuringFormEntry_andThereADialogFragmentOpen_returnsToHierarchy() {
+        rule.setUpProjectAndCopyForm("all-widgets.xml")
+            .fillNewForm("all-widgets.xml", "All widgets")
+            .clickGoToArrow()
+            .clickOnGroup("Select one widgets")
+            .clickOnQuestion("Select one from map widget")
+            .clickOnString(R.string.select_place)
+            .let { simulateProcessRestore(FormHierarchyPage("All widgets")) }
+
+            .pressBack(FormEntryPage("All widgets"))
+            .assertQuestion("Welcome to ODK Collect! This form showcases the different available question types (widgets).")
+    }
+
+    /**
+     * Simulate a "process restore" case where an app in the background is killed by Android
+     * to reclaim memory, change permissions etc and then the process is recreated (backstack etc)
+     * when navigated back to
+     */
+    private fun <T : Page<T>> simulateProcessRestore(destination: Page<T>): Page<T> {
+        rule.navigateAwayFromActivity()
+        rule.destroyActivity()
+
+        CollectHelpers.simulateProcessRestart()
+        rule.restoreActivity()
+
+        return destination.assertOnPage()
+    }
+}

collect_app/src/androidTest/java/org/odk/collect/android/feature/formentry/SavePointTest.kt

@@ -109,7 +109,7 @@ class SavePointTest {
         rule.setUpProjectAndCopyForm("two-question-audit.xml")
             .fillNewForm("two-question-audit.xml", "Two Question")
             .answerQuestion("What is your name?", "Alexei")
-            .let { simulateProcessRestore() }
+            .let { simulateProcessDeath() }
 
         // Start blank form and check save point is loaded
         rule.fillNewForm("two-question-audit.xml", FormHierarchyPage("Two Question"))
@@ -148,7 +148,7 @@ class SavePointTest {
         rule.editForm("two-question-audit.xml", "Two Question")
             .clickGoToStart()
             .answerQuestion("What is your name?", "Alexei")
-            .let { simulateProcessRestore() }
+            .let { simulateProcessDeath() }
 
         // Edit instance and check save point is loaded
         rule.editForm("two-question-audit.xml", "Two Question")
@@ -188,7 +188,7 @@ class SavePointTest {
         // Create save point for blank form
         rule.fillNewForm("two-question-audit.xml", "Two Question")
             .answerQuestion("What is your name?", "Alexei")
-            .let { simulateProcessRestore() }
+            .let { simulateProcessDeath() }
 
         // Check editing instance doesn't load save point
         rule.editForm("two-question-audit.xml", "Two Question")
@@ -212,7 +212,7 @@ class SavePointTest {
         rule.editForm("two-question-audit.xml", "Two Question")
             .clickGoToStart()
             .answerQuestion("What is your name?", "Alexei")
-            .let { simulateProcessRestore() }
+            .let { simulateProcessDeath() }
 
         // Check starting blank form does not load save point
         rule.fillNewForm("two-question-audit.xml", "Two Question")
@@ -228,11 +228,10 @@ class SavePointTest {
     }
 
     /**
-     * Simulate a "process restore" case where an app in the background is killed by Android
-     * to reclaim memory, change permissions etc
+     * Simulate a "process death" case where an app in the background is killed
      */
-    private fun simulateProcessRestore(): FormEntryActivityTestRule {
-        rule.saveInstanceStateForActivity()
+    private fun simulateProcessDeath(): FormEntryActivityTestRule {
+        rule.navigateAwayFromActivity()
             .destroyActivity()
 
         CollectHelpers.simulateProcessRestart()

collect_app/src/androidTest/java/org/odk/collect/android/support/ActivityHelpers.java

@@ -1,18 +1,19 @@
 package org.odk.collect.android.support;
 
+import static androidx.test.espresso.Espresso.onView;
+import static androidx.test.espresso.matcher.ViewMatchers.isAssignableFrom;
+import static androidx.test.espresso.matcher.ViewMatchers.isDisplayed;
+import static androidx.test.espresso.matcher.ViewMatchers.withId;
+import static org.hamcrest.core.AllOf.allOf;
+
 import android.app.Activity;
+import android.view.ContextThemeWrapper;
 import android.view.View;
 
-import androidx.test.espresso.Espresso;
 import androidx.test.espresso.UiController;
 import androidx.test.espresso.ViewAction;
-import androidx.test.espresso.matcher.ViewMatchers;
 
 import org.hamcrest.Matcher;
-import org.hamcrest.core.AllOf;
-
-import static androidx.test.espresso.matcher.ViewMatchers.isAssignableFrom;
-import static androidx.test.espresso.matcher.ViewMatchers.isDisplayed;
 
 public final class ActivityHelpers {
 
@@ -21,7 +22,7 @@ private ActivityHelpers() {
 
     public static Activity getActivity() {
         final Activity[] currentActivity = new Activity[1];
-        Espresso.onView(AllOf.allOf(ViewMatchers.withId(android.R.id.content), isDisplayed())).perform(new ViewAction() {
+        ViewAction getActivityViewAction = new ViewAction() {
             @Override
             public Matcher<View> getConstraints() {
                 return isAssignableFrom(View.class);
@@ -35,11 +36,16 @@ public String getDescription() {
             @Override
             public void perform(UiController uiController, View view) {
                 if (view.getContext() instanceof Activity) {
-                    Activity activity1 = (Activity) view.getContext();
-                    currentActivity[0] = activity1;
+                    Activity activity = (Activity) view.getContext();
+                    currentActivity[0] = activity;
+                } else if (view.getContext() instanceof ContextThemeWrapper) {
+                    Activity activity = (Activity) ((ContextThemeWrapper) view.getContext()).getBaseContext();
+                    currentActivity[0] = activity;
                 }
             }
-        });
+        };
+
+        onView(allOf(withId(android.R.id.content), isDisplayed())).perform(getActivityViewAction);
         return currentActivity[0];
     }
 }

collect_app/src/androidTest/java/org/odk/collect/android/support/CollectHelpers.kt

@@ -22,6 +22,8 @@ object CollectHelpers {
     }
 
     fun simulateProcessRestart(appDependencyModule: AppDependencyModule? = null) {
+        ApplicationProvider.getApplicationContext<Collect>().getState().clear()
+
         val newComponent =
             overrideAppDependencyModule(appDependencyModule ?: AppDependencyModule())
 

collect_app/src/androidTest/java/org/odk/collect/android/support/rules/FormEntryActivityTestRule.kt

@@ -4,7 +4,6 @@ import android.app.Activity
 import android.app.Application
 import android.content.Intent
 import android.os.Bundle
-import android.os.PersistableBundle
 import androidx.lifecycle.Lifecycle
 import androidx.test.core.app.ActivityScenario
 import androidx.test.core.app.ApplicationProvider
@@ -13,12 +12,15 @@ import org.odk.collect.android.activities.FormFillingActivity
 import org.odk.collect.android.external.FormsContract
 import org.odk.collect.android.formmanagement.FormFillingIntentFactory
 import org.odk.collect.android.injection.DaggerUtils
+import org.odk.collect.android.injection.config.AppDependencyModule
 import org.odk.collect.android.storage.StorageSubdirectory
-import org.odk.collect.android.support.ActivityHelpers
+import org.odk.collect.android.support.CollectHelpers
 import org.odk.collect.android.support.StorageUtils
 import org.odk.collect.android.support.pages.FormEntryPage
 import org.odk.collect.android.support.pages.FormHierarchyPage
 import org.odk.collect.android.support.pages.Page
+import org.odk.collect.androidshared.system.SavedInstanceStateProvider
+import org.odk.collect.androidtest.ActivityScenarioExtensions.saveInstanceState
 import org.odk.collect.projects.Project
 import timber.log.Timber
 import java.io.IOException
@@ -28,6 +30,20 @@ class FormEntryActivityTestRule : ExternalResource() {
     private lateinit var intent: Intent
     private lateinit var scenario: ActivityScenario<Activity>
 
+    private var outState: Bundle? = null
+
+    private val savedInstanceStateProvider = InMemSavedInstanceStateProvider()
+
+    override fun before() {
+        super.before()
+
+        CollectHelpers.overrideAppDependencyModule(object : AppDependencyModule() {
+            override fun providesSavedInstanceStateProvider(): SavedInstanceStateProvider {
+                return savedInstanceStateProvider
+            }
+        })
+    }
+
     override fun after() {
         try {
             scenario.close()
@@ -67,28 +83,22 @@ class FormEntryActivityTestRule : ExternalResource() {
         return FormHierarchyPage(instanceName).assertOnPage()
     }
 
-    fun saveInstanceStateForActivity(): FormEntryActivityTestRule {
-        scenario.onActivity {
-            it.onSaveInstanceState(Bundle(), PersistableBundle())
-        }
-
+    fun navigateAwayFromActivity(): FormEntryActivityTestRule {
+        scenario.moveToState(Lifecycle.State.STARTED)
+        outState = scenario.saveInstanceState()
         return this
     }
 
     fun destroyActivity(): FormEntryActivityTestRule {
-        lateinit var scenarioActivity: Activity
-        scenario.onActivity {
-            scenarioActivity = it
-        }
-
-        if (ActivityHelpers.getActivity() != scenarioActivity) {
-            throw IllegalStateException("Can't destroy backstack!")
-        }
-
         scenario.moveToState(Lifecycle.State.DESTROYED)
         return this
     }
 
+    fun restoreActivity() {
+        savedInstanceStateProvider.setState(outState)
+        scenario = ActivityScenario.launch(intent)
+    }
+
     private fun createNewFormIntent(formFilename: String): Intent {
         val application = ApplicationProvider.getApplicationContext<Application>()
         val formPath = DaggerUtils.getComponent(application).storagePathProvider()
@@ -98,7 +108,11 @@ class FormEntryActivityTestRule : ExternalResource() {
         val projectId = DaggerUtils.getComponent(application).currentProjectProvider()
             .getCurrentProject().uuid
 
-        return FormFillingIntentFactory.newInstanceIntent(application, FormsContract.getUri(projectId, form!!.dbId), FormFillingActivity::class)
+        return FormFillingIntentFactory.newInstanceIntent(
+            application,
+            FormsContract.getUri(projectId, form!!.dbId),
+            FormFillingActivity::class
+        )
     }
 
     private fun createEditFormIntent(formFilename: String): Intent {
@@ -120,3 +134,22 @@ class FormEntryActivityTestRule : ExternalResource() {
         )
     }
 }
+
+private class InMemSavedInstanceStateProvider : SavedInstanceStateProvider {
+
+    private var bundle: Bundle? = null
+
+    fun setState(savedInstanceState: Bundle?) {
+        bundle = savedInstanceState
+    }
+
+    override fun getState(savedInstanceState: Bundle?): Bundle? {
+        return if (bundle != null) {
+            bundle.also {
+                bundle = null
+            }
+        } else {
+            savedInstanceState
+        }
+    }
+}

collect_app/src/androidTest/java/org/odk/collect/android/support/rules/ResetStateRule.kt

@@ -30,7 +30,6 @@ private class ResetStateStatement(
 
         clearPrefs(oldComponent)
         clearDisk(oldComponent)
-        clearAppState(application)
         setTestState()
         CollectHelpers.simulateProcessRestart(appDependencyModule)
         base.evaluate()