documenting the rule and reflection helper

vector/src/androidTest/java/im/vector/app/ClearCurrentSessionRule.kt

@@ -28,6 +28,11 @@ import org.junit.runner.Description
 import org.junit.runners.model.Statement
 import kotlin.reflect.KClass
 
+/**
+ * A TestRule to reset and clear the current Session.
+ * If a Session is active it will be signed out and cleared from the ActiveSessionHolder.
+ * The VectorPreferences and AnalyticsDatastore are also cleared in an attempt to recreate a fresh base.
+ */
 class ClearCurrentSessionRule : TestWatcher() {
     override fun apply(base: Statement, description: Description): Statement {
         val context = InstrumentationRegistry.getInstrumentation().targetContext
@@ -46,6 +51,10 @@ class ClearCurrentSessionRule : TestWatcher() {
 
 private fun KClass<*>.asTopLevel() = Class.forName("${qualifiedName}Kt")
 
+/**
+ * Fetches the top level, private [Context.dataStore] extension property from [im.vector.app.features.analytics.store.AnalyticsStore]
+ * via reflection to avoid exposing property to all callers.
+ */
 @Suppress("UNCHECKED_CAST")
 private fun reflectAnalyticDatastore(context: Context): DataStore<Preferences> {
     val klass = AnalyticsStore::class.asTopLevel()

vector/src/main/java/im/vector/app/features/analytics/store/AnalyticsStore.kt

@@ -29,6 +29,9 @@ import kotlinx.coroutines.flow.map
 import org.matrix.android.sdk.api.extensions.orFalse
 import javax.inject.Inject
 
+/**
+ * Also accessed via reflection by the instrumentation tests @see [im.vector.app.ClearCurrentSessionRule].
+ */
 private val Context.dataStore: DataStore<Preferences> by preferencesDataStore(name = "vector_analytics")
 
 /**