Do not show update messages for profile key updates.

app/src/main/java/org/thoughtcrime/securesms/groups/v2/processing/GroupsV2StateProcessor.java

@@ -272,9 +272,13 @@ public final class GroupsV2StateProcessor {
 
     private void insertUpdateMessages(long timestamp, Collection<GroupLogEntry> processedLogEntries) {
       for (GroupLogEntry entry : processedLogEntries) {
+        if (entry.getChange() != null && DecryptedGroupUtil.changeIsEmptyExceptForProfileKeyChanges(entry.getChange())) {
+          Log.d(TAG, "Skipping profile key changes only update message");
+        } else {
           storeMessage(GroupProtoUtil.createDecryptedGroupV2Context(masterKey, entry.getGroup(), entry.getChange(), null), timestamp);
         }
       }
+    }
 
     private void persistLearnedProfileKeys(@NonNull GlobalGroupState globalGroupState) {
       final ProfileKeySet profileKeys = new ProfileKeySet();

libsignal/service/src/main/java/org/whispersystems/signalservice/api/groupsv2/DecryptedGroupUtil.java

@@ -23,6 +23,8 @@ import java.util.UUID;
 
 public final class DecryptedGroupUtil {
 
+  static final int MAX_CHANGE_FIELD = 14;
+
   public static Set<UUID> toUuidSet(Collection<DecryptedMember> membersList) {
     HashSet<UUID> uuids = new HashSet<>(membersList.size());
 
@@ -282,6 +284,29 @@ public final class DecryptedGroupUtil {
                                                                             .orNull());
   }
 
+  public static boolean changeIsEmpty(DecryptedGroupChange change) {
+    return change.getModifiedProfileKeysCount()   == 0 && // field 6
+           changeIsEmptyExceptForProfileKeyChanges(change);
+  }
+
+  public static boolean changeIsEmptyExceptForProfileKeyChanges(DecryptedGroupChange change) {
+    return change.getNewMembersCount()            == 0 && // field 3
+           change.getDeleteMembersCount()         == 0 && // field 4
+           change.getModifyMemberRolesCount()     == 0 && // field 5
+           change.getNewPendingMembersCount()     == 0 && // field 7
+           change.getDeletePendingMembersCount()  == 0 && // field 8
+           change.getPromotePendingMembersCount() == 0 && // field 9
+           !change.hasNewTitle()                       && // field 10
+           !change.hasNewAvatar()                      && // field 11
+           !change.hasNewTimer()                       && // field 12
+           isSet(change.getNewAttributeAccess())       && // field 13
+           isSet(change.getNewMemberAccess());            // field 14
+  }
+
+  static boolean isSet(AccessControl.AccessRequired newAttributeAccess) {
+    return newAttributeAccess == AccessControl.AccessRequired.UNKNOWN;
+  }
+
   public static class NotAbleToApplyChangeException extends Throwable {
   }
 }

libsignal/service/src/test/java/org/whispersystems/signalservice/api/groupsv2/DecryptedGroupUtil_empty_Test.java

@@ -0,0 +1,161 @@
+package org.whispersystems.signalservice.api.groupsv2;
+
+import org.junit.Test;
+import org.signal.storageservice.protos.groups.AccessControl;
+import org.signal.storageservice.protos.groups.local.DecryptedGroupChange;
+import org.signal.storageservice.protos.groups.local.DecryptedString;
+import org.signal.storageservice.protos.groups.local.DecryptedTimer;
+import org.whispersystems.signalservice.api.util.UuidUtil;
+
+import java.util.UUID;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
+import static org.whispersystems.signalservice.api.groupsv2.ProtoTestUtils.member;
+import static org.whispersystems.signalservice.api.groupsv2.ProtoTestUtils.pendingMember;
+import static org.whispersystems.signalservice.api.groupsv2.ProtoTestUtils.pendingMemberRemoval;
+import static org.whispersystems.signalservice.api.groupsv2.ProtoTestUtils.promoteAdmin;
+import static org.whispersystems.signalservice.api.groupsv2.ProtoTestUtils.randomProfileKey;
+import static org.whispersystems.signalservice.api.groupsv2.ProtobufTestUtils.getMaxDeclaredFieldNumber;
+
+public final class DecryptedGroupUtil_empty_Test {
+
+  /**
+   * Reflects over the generated protobuf class and ensures that no new fields have been added since we wrote this.
+   * <p>
+   * If we didn't, newly added fields would easily affect {@link DecryptedGroupUtil}'s ability to detect non-empty change states.
+   */
+  @Test
+  public void ensure_DecryptedGroupUtil_knows_about_all_fields_of_DecryptedGroupChange() {
+    int maxFieldFound = getMaxDeclaredFieldNumber(DecryptedGroupChange.class);
+
+    assertEquals("DecryptedGroupUtil and its tests need updating to account for new fields on " + DecryptedGroupChange.class.getName(),
+                 DecryptedGroupUtil.MAX_CHANGE_FIELD, maxFieldFound);
+  }
+
+  @Test
+  public void empty_change_set() {
+    assertTrue(DecryptedGroupUtil.changeIsEmpty(DecryptedGroupChange.newBuilder().build()));
+  }
+
+  @Test
+  public void not_empty_with_add_member_field_3() {
+    DecryptedGroupChange change = DecryptedGroupChange.newBuilder()
+                                                      .addNewMembers(member(UUID.randomUUID()))
+                                                      .build();
+
+    assertFalse(DecryptedGroupUtil.changeIsEmpty(change));
+    assertFalse(DecryptedGroupUtil.changeIsEmptyExceptForProfileKeyChanges(change));
+  }
+
+  @Test
+  public void not_empty_with_delete_member_field_4() {
+    DecryptedGroupChange change = DecryptedGroupChange.newBuilder()
+                                                      .addDeleteMembers(UuidUtil.toByteString(UUID.randomUUID()))
+                                                      .build();
+
+    assertFalse(DecryptedGroupUtil.changeIsEmpty(change));
+    assertFalse(DecryptedGroupUtil.changeIsEmptyExceptForProfileKeyChanges(change));
+  }
+
+  @Test
+  public void not_empty_with_modify_member_roles_field_5() {
+    DecryptedGroupChange change = DecryptedGroupChange.newBuilder()
+                                                      .addModifyMemberRoles(promoteAdmin(UUID.randomUUID()))
+                                                      .build();
+
+    assertFalse(DecryptedGroupUtil.changeIsEmpty(change));
+    assertFalse(DecryptedGroupUtil.changeIsEmptyExceptForProfileKeyChanges(change));
+  }
+
+  @Test
+  public void not_empty_with_modify_profile_keys_field_6() {
+    DecryptedGroupChange change = DecryptedGroupChange.newBuilder()
+                                                      .addModifiedProfileKeys(member(UUID.randomUUID(), randomProfileKey()))
+                                                      .build();
+
+    assertFalse(DecryptedGroupUtil.changeIsEmpty(change));
+    assertTrue(DecryptedGroupUtil.changeIsEmptyExceptForProfileKeyChanges(change));
+  }
+
+  @Test
+  public void not_empty_with_add_pending_members_field_7() {
+    DecryptedGroupChange change = DecryptedGroupChange.newBuilder()
+                                                      .addNewPendingMembers(pendingMember(UUID.randomUUID()))
+                                                      .build();
+
+    assertFalse(DecryptedGroupUtil.changeIsEmpty(change));
+    assertFalse(DecryptedGroupUtil.changeIsEmptyExceptForProfileKeyChanges(change));
+  }
+
+  @Test
+  public void not_empty_with_delete_pending_members_field_8() {
+    DecryptedGroupChange change = DecryptedGroupChange.newBuilder()
+                                                      .addDeletePendingMembers(pendingMemberRemoval(UUID.randomUUID()))
+                                                      .build();
+
+    assertFalse(DecryptedGroupUtil.changeIsEmpty(change));
+    assertFalse(DecryptedGroupUtil.changeIsEmptyExceptForProfileKeyChanges(change));
+  }
+
+  @Test
+  public void not_empty_with_promote_delete_pending_members_field_9() {
+    DecryptedGroupChange change = DecryptedGroupChange.newBuilder()
+                                                      .addPromotePendingMembers(member(UUID.randomUUID()))
+                                                      .build();
+
+    assertFalse(DecryptedGroupUtil.changeIsEmpty(change));
+    assertFalse(DecryptedGroupUtil.changeIsEmptyExceptForProfileKeyChanges(change));
+  }
+
+  @Test
+  public void not_empty_with_modify_title_field_10() {
+    DecryptedGroupChange change = DecryptedGroupChange.newBuilder()
+                                                      .setNewTitle(DecryptedString.newBuilder().setValue("New title"))
+                                                      .build();
+
+    assertFalse(DecryptedGroupUtil.changeIsEmpty(change));
+    assertFalse(DecryptedGroupUtil.changeIsEmptyExceptForProfileKeyChanges(change));
+  }
+
+  @Test
+  public void not_empty_with_modify_avatar_field_11() {
+    DecryptedGroupChange change = DecryptedGroupChange.newBuilder()
+                                                      .setNewAvatar(DecryptedString.newBuilder().setValue("New Avatar"))
+                                                      .build();
+
+    assertFalse(DecryptedGroupUtil.changeIsEmpty(change));
+    assertFalse(DecryptedGroupUtil.changeIsEmptyExceptForProfileKeyChanges(change));
+  }
+
+  @Test
+  public void not_empty_with_modify_disappearing_message_timer_field_12() {
+    DecryptedGroupChange change = DecryptedGroupChange.newBuilder()
+                                                      .setNewTimer(DecryptedTimer.newBuilder().setDuration(60))
+                                                      .build();
+
+    assertFalse(DecryptedGroupUtil.changeIsEmpty(change));
+    assertFalse(DecryptedGroupUtil.changeIsEmptyExceptForProfileKeyChanges(change));
+  }
+
+  @Test
+  public void not_empty_with_modify_attributes_field_13() {
+    DecryptedGroupChange change = DecryptedGroupChange.newBuilder()
+                                                      .setNewAttributeAccess(AccessControl.AccessRequired.ADMINISTRATOR)
+                                                      .build();
+
+    assertFalse(DecryptedGroupUtil.changeIsEmpty(change));
+    assertFalse(DecryptedGroupUtil.changeIsEmptyExceptForProfileKeyChanges(change));
+  }
+
+  @Test
+  public void not_empty_with_modify_member_access_field_14() {
+    DecryptedGroupChange change = DecryptedGroupChange.newBuilder()
+                                                      .setNewMemberAccess(AccessControl.AccessRequired.MEMBER)
+                                                      .build();
+
+    assertFalse(DecryptedGroupUtil.changeIsEmpty(change));
+    assertFalse(DecryptedGroupUtil.changeIsEmptyExceptForProfileKeyChanges(change));
+  }
+}

libsignal/service/src/test/java/org/whispersystems/signalservice/api/groupsv2/GroupChangeUtilTest.java

@@ -3,11 +3,10 @@ package org.whispersystems.signalservice.api.groupsv2;
 import org.junit.Test;
 import org.signal.storageservice.protos.groups.GroupChange;
 
-import java.util.stream.Stream;
-
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertTrue;
+import static org.whispersystems.signalservice.api.groupsv2.ProtobufTestUtils.getMaxDeclaredFieldNumber;
 
 public final class GroupChangeUtilTest {
 
@@ -18,17 +17,7 @@ public final class GroupChangeUtilTest {
    */
   @Test
   public void ensure_GroupChangeUtil_knows_about_all_fields_of_GroupChange_Actions() {
-    int maxFieldFound = Stream.of(GroupChange.Actions.class.getFields())
+    int maxFieldFound = getMaxDeclaredFieldNumber(GroupChange.Actions.class);
-                          .filter(f -> f.getType() == int.class)
-                          .mapToInt(f -> {
-                            try {
-                              return (int) f.get(null);
-                            } catch (IllegalAccessException e) {
-                              throw new AssertionError(e);
-                            }
-                          })
-                          .max()
-                          .orElse(0);
 
     assertEquals("GroupChangeUtil and its tests need updating to account for new fields on " + GroupChange.Actions.class.getName(),
                  GroupChangeUtil.CHANGE_ACTION_MAX_FIELD, maxFieldFound);

libsignal/service/src/test/java/org/whispersystems/signalservice/api/groupsv2/ProtobufTestUtils.java

@@ -0,0 +1,25 @@
+package org.whispersystems.signalservice.api.groupsv2;
+
+import com.google.protobuf.MessageLite;
+
+import java.util.stream.Stream;
+
+final class ProtobufTestUtils {
+
+  /**
+   * Finds the largest declared field number in the supplied protobuf class.
+   */
+  static int getMaxDeclaredFieldNumber(Class<? extends MessageLite> protobufClass) {
+    return Stream.of(protobufClass.getFields())
+                 .filter(f -> f.getType() == int.class)
+                 .mapToInt(f -> {
+                   try {
+                     return (int) f.get(null);
+                   } catch (IllegalAccessException e) {
+                     throw new AssertionError(e);
+                   }
+                 })
+                 .max()
+                 .orElse(0);
+  }
+}