Keep protobuf's parseFrom so the GroupUpdated serialization fix survives the shrinker

app/proguard-rules.pro

@@ -133,6 +133,13 @@
 # Preserve class names for Kryo
 -keepnames class org.session.libsession.messaging.messages.Destination$**
 
+# Protobuf messages are persisted as their own wire format and rebuilt through parseFrom,
+# which is reached reflectively -- invisible to the shrinker, which otherwise removes it and
+# leaves every queued message carrying a protobuf unreadable after a restart.
+-keepclassmembers class * extends com.google.protobuf.GeneratedMessage {
+    public static *** parseFrom(byte[]);
+}
+
 ########## OPEN GROUP API (MESSAGES) ##########
 -keep class org.session.libsession.messaging.open_groups.OpenGroupApi$Message { *; }
 -keepclassmembers class org.session.libsession.messaging.open_groups.OpenGroupApi$Message { <init>(); }

app/src/test/java/org/session/libsession/messaging/jobs/JobKryoTest.kt

@@ -2,10 +2,17 @@ package org.session.libsession.messaging.jobs
 
 import com.esotericsoftware.kryo.io.Input
 import com.esotericsoftware.kryo.io.Output
+import io.mockk.every
+import io.mockk.mockk
+import io.mockk.slot
 import org.junit.Assert.assertEquals
+import org.junit.Assert.assertNotNull
 import org.junit.Assert.assertTrue
 import org.junit.Test
+import org.session.libsession.messaging.messages.Destination
+import org.session.libsession.messaging.messages.Message
 import org.session.libsession.messaging.messages.control.GroupUpdated
+import org.session.libsession.messaging.utilities.Data
 import org.session.protos.SessionProtos
 
 class JobKryoTest {
@@ -26,6 +33,40 @@ class JobKryoTest {
         assertEquals(message.sentTimestamp, restored.sentTimestamp)
     }
 
+    /**
+     * The round trip above proves the serializer; this proves the job is wired to it, in both
+     * directions — a `serialize()` and a `create()` that disagree lose the message silently.
+     */
+    @Test
+    fun `a GroupUpdated send job survives serialize and deserialize`() {
+        val message = GroupUpdated(
+            SessionProtos.GroupUpdateMessage.newBuilder()
+                .setMemberLeftMessage(SessionProtos.GroupUpdateMemberLeftMessage.getDefaultInstance())
+                .build()
+        )
+
+        val restored = slot<Message>()
+        val factory = mockk<MessageSendJob.Factory> {
+            every { create(any<Data>()) } answers { callOriginal() }
+            every { create(capture(restored), any(), any()) } returns mockk(relaxed = true)
+        }
+
+        assertNotNull(factory.create(sendJob(message).serialize()))
+        assertEquals(message.inner, (restored.captured as GroupUpdated).inner)
+    }
+
+    private fun sendJob(message: Message) = MessageSendJob(
+        message = message,
+        destination = Destination.ClosedGroup("03${"11".repeat(32)}"),
+        statusCallback = null,
+        attachmentUploadJobFactory = mockk(relaxed = true),
+        messageDataProvider = mockk(relaxed = true),
+        storage = mockk(relaxed = true),
+        configFactory = mockk(relaxed = true),
+        messageSender = mockk(relaxed = true),
+        jobQueue = mockk(relaxed = true),
+    )
+
     private fun roundTrip(value: Any): Any {
         val output = Output(ByteArray(4096), Job.MAX_BUFFER_SIZE_BYTES)
         jobKryo().writeClassAndObject(output, value)