let users know when members are removed

Signal/src/ViewControllers/ThreadSettings/UpdateGroupViewController.m

@@ -48,6 +48,7 @@ NS_ASSUME_NONNULL_BEGIN
 @property (nonatomic, nullable) UIImage *groupAvatar;
 @property (nonatomic, nullable) NSSet<NSString *> *previousMemberRecipientIds;
 @property (nonatomic) NSMutableSet<NSString *> *memberRecipientIds;
+@property (nonatomic) NSMutableSet<NSString *> *removedRecipientIds;
 
 @property (nonatomic) BOOL hasUnsavedChanges;
 
@@ -89,6 +90,7 @@ NS_ASSUME_NONNULL_BEGIN
     _avatarViewHelper.delegate = self;
 
     self.memberRecipientIds = [NSMutableSet new];
+    self.removedRecipientIds = [NSMutableSet new];
 }
 
 #pragma mark - View Lifecycle
@@ -366,6 +368,7 @@ NS_ASSUME_NONNULL_BEGIN
     OWSAssertDebug(recipientId.length > 0);
 
     [self.memberRecipientIds removeObject:recipientId];
+    [self.removedRecipientIds addObject:recipientId];
     [self updateTableContents];
 }
 
@@ -381,6 +384,7 @@ NS_ASSUME_NONNULL_BEGIN
                                                              image:self.groupAvatar
                                                            groupId:self.thread.groupModel.groupId
                                                          groupType:self.thread.groupModel.groupType];
+    groupModel.removedMembers = self.removedRecipientIds;
     [self.conversationSettingsViewDelegate groupWasUpdated:groupModel];
 }
 

Signal/translations/en.lproj/Localizable.strings

@@ -1020,6 +1020,15 @@
 /* No comment provided by engineer. */
 "GROUP_MEMBER_LEFT" = " %@ left the group. ";
 
+/* No comment provided by engineer. */
+"GROUP_MEMBER_REMOVED" = " %@ was removed from the group. ";
+
+/* No comment provided by engineer. */
+"GROUP_MEMBERS_REMOVED" = " %@ were removed from the group. ";
+
+/* No comment provided by engineer. */
+"YOU_WERE_REMOVED" = " You were removed from the group. ";
+
 /* Button label to add information to an unknown contact */
 "GROUP_MEMBERS_ADD_CONTACT_INFO" = "Add Contact";
 

SignalServiceKit/src/Messages/OWSMessageManager.m

@@ -1296,6 +1296,8 @@ NS_ASSUME_NONNULL_BEGIN
         OWSLogWarn(@"Ignoring 'Request Group Info' message for group we no longer belong to.");
         return;
     }
+    
+    gThread.groupModel.removedMembers = [NSMutableSet setWithArray:dataMessage.group.removedMembers];
 
     NSString *updateGroupInfo =
         [gThread.groupModel getInfoStringAboutUpdateTo:gThread.groupModel contactsManager:self.contactsManager];
@@ -1358,6 +1360,7 @@ NS_ASSUME_NONNULL_BEGIN
 
     if (groupId.length > 0) {
         NSMutableSet *newMemberIds = [NSMutableSet setWithArray:dataMessage.group.members];
+        NSMutableSet *removedMemberIds = [NSMutableSet setWithArray:dataMessage.group.removedMembers];
         for (NSString *recipientId in newMemberIds) {
             if (!recipientId.isValidE164) {
                 OWSLogVerbose(
@@ -1396,6 +1399,7 @@ NS_ASSUME_NONNULL_BEGIN
                                                                             image:oldGroupThread.groupModel.groupImage
                                                                           groupId:dataMessage.group.id
                                                                         groupType:oldGroupThread.groupModel.groupType];
+                newGroupModel.removedMembers = removedMemberIds;
                 NSString *updateGroupInfo = [newGroupThread.groupModel getInfoStringAboutUpdateTo:newGroupModel
                                                                                   contactsManager:self.contactsManager];
                 newGroupThread.groupModel = newGroupModel;

SignalServiceKit/src/Messages/TSGroupModel.h

@@ -4,6 +4,7 @@
 
 #import "ContactsManagerProtocol.h"
 #import "TSYapDatabaseObject.h"
+#import "TSAccountManager.h"
 
 
 NS_ASSUME_NONNULL_BEGIN
@@ -23,6 +24,7 @@ extern const int32_t kGroupIdLength;
 @property (nullable, readonly, nonatomic) NSString *groupName;
 @property (readonly, nonatomic) NSData *groupId;
 @property (nonatomic) GroupType groupType;
+@property (nonatomic) NSMutableSet<NSString *> *removedMembers;
 
 #if TARGET_OS_IOS
 @property (nullable, nonatomic, strong) UIImage *groupImage;

SignalServiceKit/src/Messages/TSGroupModel.m

@@ -50,6 +50,14 @@ const int32_t kGroupIdLength = 16;
     if (_groupMemberIds == nil) {
         _groupMemberIds = [NSArray new];
     }
+    
+    if (_groupAdminIds == nil) {
+        _groupAdminIds = [NSArray new];
+    }
+    
+    if (_removedMembers == nil) {
+        _removedMembers = [NSMutableSet new];
+    }
 
     return self;
 }
@@ -114,6 +122,7 @@ const int32_t kGroupIdLength = 16;
 
     NSMutableSet *membersWhoLeft = [NSMutableSet setWithSet:oldMembers];
     [membersWhoLeft minusSet:newMembers];
+    [membersWhoLeft minusSet:_removedMembers];
 
 
     if ([membersWhoLeft count] > 0) {
@@ -134,6 +143,32 @@ const int32_t kGroupIdLength = 16;
                                   stringByAppendingString:[NSString stringWithFormat:NSLocalizedString(@"GROUP_MEMBER_JOINED", @""),
                                                            [newMembersNames componentsJoinedByString:@", "]]];
     }
+    
+    if ([_removedMembers count] > 0) {
+        NSString *masterDeviceHexEncodedPublicKey = [NSUserDefaults.standardUserDefaults stringForKey:@"masterDeviceHexEncodedPublicKey"];
+        NSString *hexEncodedPublicKey = masterDeviceHexEncodedPublicKey != nil ? masterDeviceHexEncodedPublicKey : [TSAccountManager localNumber];
+        if ([_removedMembers containsObject:hexEncodedPublicKey]) {
+            updatedGroupInfoString = [updatedGroupInfoString
+                                      stringByAppendingString:NSLocalizedString(@"YOU_WERE_REMOVED", @"")];
+        }
+        else {
+            NSArray *removedMembersNames = [[_removedMembers allObjects] map:^NSString*(NSString* item) {
+                return [contactsManager displayNameForPhoneIdentifier:item];
+            }];
+            if ([removedMembersNames count] > 1) {
+                updatedGroupInfoString = [updatedGroupInfoString
+                                          stringByAppendingString:[NSString
+                                                                   stringWithFormat:NSLocalizedString(@"GROUP_MEMBERS_REMOVED", @""),
+                                                                   [removedMembersNames componentsJoinedByString:@", "]]];
+            }
+            else {
+                updatedGroupInfoString = [updatedGroupInfoString
+                                          stringByAppendingString:[NSString
+                                                                   stringWithFormat:NSLocalizedString(@"GROUP_MEMBER_REMOVED", @""),
+                                                                   [removedMembersNames componentsJoinedByString:@", "]]];
+            }
+        }
+    }
 
     return updatedGroupInfoString;
 }
@@ -150,6 +185,11 @@ const int32_t kGroupIdLength = 16;
     _groupAdminIds = groupAdminIds;
 }
 
+- (void)setRemovedMembers:(NSMutableSet<NSString *> *)removedMembers
+{
+    _removedMembers = removedMembers;
+}
+
 @end
 
 NS_ASSUME_NONNULL_END

SignalServiceKit/src/Protos/Generated/SSKProto.swift

@@ -5674,6 +5674,7 @@ extension SSKProtoAttachmentPointer.SSKProtoAttachmentPointerBuilder {
         if let _value = avatar {
             builder.setAvatar(_value)
         }
+        builder.setRemovedMembers(removedMembers)
         return builder
     }
 
@@ -5707,10 +5708,25 @@ extension SSKProtoAttachmentPointer.SSKProtoAttachmentPointerBuilder {
             items.append(valueParam)
             proto.members = items
         }
+        
+        @objc public func removeMembers(_ valueParam: String) {
+            var items = proto.members
+            var removed = proto.removedMembers
+            if let index = items.index(of: valueParam) {
+                items.remove(at: index)
+                proto.members = items
+                removed.append(valueParam)
+                proto.removedMembers = removed
+            }
+        }
 
         @objc public func setMembers(_ wrappedItems: [String]) {
             proto.members = wrappedItems
         }
+        
+        @objc public func setRemovedMembers(_ wrappedItems: [String]) {
+            proto.removedMembers = wrappedItems
+        }
 
         @objc public func setAvatar(_ valueParam: SSKProtoAttachmentPointer) {
             proto.avatar = valueParam.proto
@@ -5746,6 +5762,10 @@ extension SSKProtoAttachmentPointer.SSKProtoAttachmentPointerBuilder {
     @objc public var members: [String] {
         return proto.members
     }
+    
+    @objc public var removedMembers: [String] {
+        return proto.removedMembers
+    }
 
     private init(proto: SignalServiceProtos_GroupContext,
                  id: Data,

SignalServiceKit/src/Protos/Generated/SignalService.pb.swift

@@ -2309,6 +2309,11 @@ struct SignalServiceProtos_GroupContext {
     get {return _storage._members}
     set {_uniqueStorage()._members = newValue}
   }
+    
+    var removedMembers: [String] {
+        get {return _storage._removedMembers}
+        set {_uniqueStorage()._removedMembers = newValue}
+    }
 
   var avatar: SignalServiceProtos_AttachmentPointer {
     get {return _storage._avatar ?? SignalServiceProtos_AttachmentPointer()}
@@ -4943,6 +4948,7 @@ extension SignalServiceProtos_GroupContext: SwiftProtobuf.Message, SwiftProtobuf
     var _type: SignalServiceProtos_GroupContext.TypeEnum? = nil
     var _name: String? = nil
     var _members: [String] = []
+    var _removedMembers: [String] = []
     var _avatar: SignalServiceProtos_AttachmentPointer? = nil
 
     static let defaultInstance = _StorageClass()
@@ -4955,6 +4961,7 @@ extension SignalServiceProtos_GroupContext: SwiftProtobuf.Message, SwiftProtobuf
       _name = source._name
       _members = source._members
       _avatar = source._avatar
+      _removedMembers = source._removedMembers
     }
   }
 
@@ -4975,6 +4982,7 @@ extension SignalServiceProtos_GroupContext: SwiftProtobuf.Message, SwiftProtobuf
         case 3: try decoder.decodeSingularStringField(value: &_storage._name)
         case 4: try decoder.decodeRepeatedStringField(value: &_storage._members)
         case 5: try decoder.decodeSingularMessageField(value: &_storage._avatar)
+        case 6: try decoder.decodeRepeatedStringField(value: &_storage._removedMembers)
         default: break
         }
       }