MM-11700 Clean up handling of user display names for notifications (#9343)

* MM-11700 Clean up handling of user display names for notifications

7 files changed, 269 insertions, 72 deletions

diff --git a/app/import_functions.go b/app/import_functions.go
index 98306d3a7..cd047ba71 100644
--- a/app/import_functions.go
+++ b/app/import_functions.go
@@ -514,7 +514,7 @@ func (a *App) ImportUser(data *UserImportData, dryRun bool) *model.AppError {
 		preferences = append(preferences, model.Preference{
 			UserId:   savedUser.Id,
 			Category: model.PREFERENCE_CATEGORY_DISPLAY_SETTINGS,
-			Name:     "use_military_time",
+			Name:     model.PREFERENCE_NAME_USE_MILITARY_TIME,
 			Value:    *data.UseMilitaryTime,
 		})
 	}
@@ -523,7 +523,7 @@ func (a *App) ImportUser(data *UserImportData, dryRun bool) *model.AppError {
 		preferences = append(preferences, model.Preference{
 			UserId:   savedUser.Id,
 			Category: model.PREFERENCE_CATEGORY_DISPLAY_SETTINGS,
-			Name:     "collapse_previews",
+			Name:     model.PREFERENCE_NAME_COLLAPSE_SETTING,
 			Value:    *data.CollapsePreviews,
 		})
 	}
@@ -532,7 +532,7 @@ func (a *App) ImportUser(data *UserImportData, dryRun bool) *model.AppError {
 		preferences = append(preferences, model.Preference{
 			UserId:   savedUser.Id,
 			Category: model.PREFERENCE_CATEGORY_DISPLAY_SETTINGS,
-			Name:     "message_display",
+			Name:     model.PREFERENCE_NAME_MESSAGE_DISPLAY,
 			Value:    *data.MessageDisplay,
 		})
 	}
diff --git a/app/import_functions_test.go b/app/import_functions_test.go
index c76915ac6..2e710a3df 100644
--- a/app/import_functions_test.go
+++ b/app/import_functions_test.go
@@ -1091,10 +1091,10 @@ func TestImportImportUser(t *testing.T) {
 	}
 
 	checkPreference(t, th.App, user.Id, model.PREFERENCE_CATEGORY_THEME, "", *data.Theme)
-	checkPreference(t, th.App, user.Id, model.PREFERENCE_CATEGORY_DISPLAY_SETTINGS, "use_military_time", *data.UseMilitaryTime)
-	checkPreference(t, th.App, user.Id, model.PREFERENCE_CATEGORY_DISPLAY_SETTINGS, "collapse_previews", *data.CollapsePreviews)
-	checkPreference(t, th.App, user.Id, model.PREFERENCE_CATEGORY_DISPLAY_SETTINGS, "message_display", *data.MessageDisplay)
-	checkPreference(t, th.App, user.Id, model.PREFERENCE_CATEGORY_DISPLAY_SETTINGS, "channel_display_mode", *data.ChannelDisplayMode)
+	checkPreference(t, th.App, user.Id, model.PREFERENCE_CATEGORY_DISPLAY_SETTINGS, model.PREFERENCE_NAME_USE_MILITARY_TIME, *data.UseMilitaryTime)
+	checkPreference(t, th.App, user.Id, model.PREFERENCE_CATEGORY_DISPLAY_SETTINGS, model.PREFERENCE_NAME_COLLAPSE_SETTING, *data.CollapsePreviews)
+	checkPreference(t, th.App, user.Id, model.PREFERENCE_CATEGORY_DISPLAY_SETTINGS, model.PREFERENCE_NAME_MESSAGE_DISPLAY, *data.MessageDisplay)
+	checkPreference(t, th.App, user.Id, model.PREFERENCE_CATEGORY_DISPLAY_SETTINGS, model.PREFERENCE_NAME_CHANNEL_DISPLAY_MODE, *data.ChannelDisplayMode)
 	checkPreference(t, th.App, user.Id, model.PREFERENCE_CATEGORY_TUTORIAL_STEPS, user.Id, *data.TutorialStep)
 	checkPreference(t, th.App, user.Id, model.PREFERENCE_CATEGORY_ADVANCED_SETTINGS, "feature_enabled_markdown_preview", *data.UseMarkdownPreview)
 	checkPreference(t, th.App, user.Id, model.PREFERENCE_CATEGORY_ADVANCED_SETTINGS, "formatting", *data.UseFormatting)
@@ -1117,10 +1117,10 @@ func TestImportImportUser(t *testing.T) {
 
 	// Check their values again.
 	checkPreference(t, th.App, user.Id, model.PREFERENCE_CATEGORY_THEME, "", *data.Theme)
-	checkPreference(t, th.App, user.Id, model.PREFERENCE_CATEGORY_DISPLAY_SETTINGS, "use_military_time", *data.UseMilitaryTime)
-	checkPreference(t, th.App, user.Id, model.PREFERENCE_CATEGORY_DISPLAY_SETTINGS, "collapse_previews", *data.CollapsePreviews)
-	checkPreference(t, th.App, user.Id, model.PREFERENCE_CATEGORY_DISPLAY_SETTINGS, "message_display", *data.MessageDisplay)
-	checkPreference(t, th.App, user.Id, model.PREFERENCE_CATEGORY_DISPLAY_SETTINGS, "channel_display_mode", *data.ChannelDisplayMode)
+	checkPreference(t, th.App, user.Id, model.PREFERENCE_CATEGORY_DISPLAY_SETTINGS, model.PREFERENCE_NAME_USE_MILITARY_TIME, *data.UseMilitaryTime)
+	checkPreference(t, th.App, user.Id, model.PREFERENCE_CATEGORY_DISPLAY_SETTINGS, model.PREFERENCE_NAME_COLLAPSE_SETTING, *data.CollapsePreviews)
+	checkPreference(t, th.App, user.Id, model.PREFERENCE_CATEGORY_DISPLAY_SETTINGS, model.PREFERENCE_NAME_MESSAGE_DISPLAY, *data.MessageDisplay)
+	checkPreference(t, th.App, user.Id, model.PREFERENCE_CATEGORY_DISPLAY_SETTINGS, model.PREFERENCE_NAME_CHANNEL_DISPLAY_MODE, *data.ChannelDisplayMode)
 	checkPreference(t, th.App, user.Id, model.PREFERENCE_CATEGORY_TUTORIAL_STEPS, user.Id, *data.TutorialStep)
 
 	// Set Notify Props
diff --git a/app/notification.go b/app/notification.go
index 92b69039b..8092ba436 100644
--- a/app/notification.go
+++ b/app/notification.go
@@ -157,32 +157,11 @@ func (a *App) SendNotifications(post *model.Post, team *model.Team, channel *mod
 		updateMentionChans = append(updateMentionChans, a.Srv.Store.Channel().IncrementMentionCount(post.ChannelId, id))
 	}
 
-	var senderUsername string
-	senderName := ""
-	channelName := ""
-	if post.IsSystemMessage() {
-		senderName = utils.T("system.message.name")
-	} else {
-		if value, ok := post.Props["override_username"]; ok && post.Props["from_webhook"] == "true" && channel.Type != model.CHANNEL_DIRECT {
-			senderName = value.(string)
-			senderUsername = value.(string)
-		} else {
-			senderName = sender.Username
-			senderUsername = sender.Username
-		}
-	}
-
-	if channel.Type == model.CHANNEL_GROUP {
-		userList := []*model.User{}
-		for _, u := range profileMap {
-			if u.Id != sender.Id {
-				userList = append(userList, u)
-			}
-		}
-		userList = append(userList, sender)
-		channelName = model.GetGroupDisplayNameFromUsers(userList, false)
-	} else {
-		channelName = channel.DisplayName
+	notification := &postNotification{
+		post:       post,
+		channel:    channel,
+		profileMap: profileMap,
+		sender:     sender,
 	}
 
 	if a.Config().EmailSettings.SendEmailNotifications {
@@ -227,7 +206,7 @@ func (a *App) SendNotifications(post *model.Post, team *model.Team, channel *mod
 			autoResponderRelated := status.Status == model.STATUS_OUT_OF_OFFICE || post.Type == model.POST_AUTO_RESPONDER
 
 			if userAllowsEmails && status.Status != model.STATUS_ONLINE && profileMap[id].DeleteAt == 0 && !autoResponderRelated {
-				a.sendNotificationEmail(post, profileMap[id], channel, team, channelName, senderName, sender)
+				a.sendNotificationEmail(notification, profileMap[id], team)
 			}
 		}
 	}
@@ -310,12 +289,8 @@ func (a *App) SendNotifications(post *model.Post, team *model.Team, channel *mod
 				}
 
 				a.sendPushNotification(
-					post,
+					notification,
 					profileMap[id],
-					channel,
-					channelName,
-					sender,
-					senderName,
 					mentionedUserIds[id],
 					(channelNotification || hereNotification || allNotification),
 					replyToThreadType,
@@ -337,12 +312,8 @@ func (a *App) SendNotifications(post *model.Post, team *model.Team, channel *mod
 
 				if ShouldSendPushNotification(profileMap[id], channelMemberNotifyPropsMap[id], false, status, post) {
 					a.sendPushNotification(
-						post,
+						notification,
 						profileMap[id],
-						channel,
-						channelName,
-						sender,
-						senderName,
 						false,
 						false,
 						"",
@@ -355,9 +326,9 @@ func (a *App) SendNotifications(post *model.Post, team *model.Team, channel *mod
 	message := model.NewWebSocketEvent(model.WEBSOCKET_EVENT_POSTED, "", post.ChannelId, "", nil)
 	message.Add("post", a.PostWithProxyAddedToImageURLs(post).ToJson())
 	message.Add("channel_type", channel.Type)
-	message.Add("channel_display_name", channelName)
+	message.Add("channel_display_name", notification.GetChannelName(model.SHOW_USERNAME, ""))
 	message.Add("channel_name", channel.Name)
-	message.Add("sender_name", senderUsername)
+	message.Add("sender_name", notification.GetSenderName(model.SHOW_USERNAME, a.Config().ServiceSettings.EnablePostUsernameOverride))
 	message.Add("team_id", team.Id)
 
 	if len(post.FileIds) != 0 && fchan != nil {
@@ -628,3 +599,50 @@ func (a *App) GetMentionKeywordsInChannel(profiles map[string]*model.User, lookF
 
 	return keywords
 }
+
+// Represents either an email or push notification and contains the fields required to send it to any user.
+type postNotification struct {
+	channel    *model.Channel
+	post       *model.Post
+	profileMap map[string]*model.User
+	sender     *model.User
+}
+
+// Returns the name of the channel for this notification. For direct messages, this is the sender's name
+// preceeded by an at sign. For group messages, this is a comma-separated list of the members of the
+// channel, with an option to exclude the recipient of the message from that list.
+func (n *postNotification) GetChannelName(userNameFormat string, excludeId string) string {
+	switch n.channel.Type {
+	case model.CHANNEL_DIRECT:
+		return fmt.Sprintf("@%s", n.sender.GetDisplayName(userNameFormat))
+	case model.CHANNEL_GROUP:
+		names := []string{}
+		for _, user := range n.profileMap {
+			if user.Id != excludeId {
+				names = append(names, user.GetDisplayName(userNameFormat))
+			}
+		}
+
+		sort.Strings(names)
+
+		return strings.Join(names, ", ")
+	default:
+		return n.channel.DisplayName
+	}
+}
+
+// Returns the name of the sender of this notification, accounting for things like system messages
+// and whether or not the username has been overridden by an integration.
+func (n *postNotification) GetSenderName(userNameFormat string, overridesAllowed bool) string {
+	if n.post.IsSystemMessage() {
+		return utils.T("system.message.name")
+	}
+
+	if overridesAllowed && n.channel.Type != model.CHANNEL_DIRECT {
+		if value, ok := n.post.Props["override_username"]; ok && n.post.Props["from_webhook"] == "true" {
+			return value.(string)
+		}
+	}
+
+	return n.sender.GetDisplayName(userNameFormat)
+}
diff --git a/app/notification_email.go b/app/notification_email.go
index b3835a4ee..cfc1bb4fd 100644
--- a/app/notification_email.go
+++ b/app/notification_email.go
@@ -17,7 +17,10 @@ import (
 	"github.com/nicksnyder/go-i18n/i18n"
 )
 
-func (a *App) sendNotificationEmail(post *model.Post, user *model.User, channel *model.Channel, team *model.Team, channelName string, senderName string, sender *model.User) *model.AppError {
+func (a *App) sendNotificationEmail(notification *postNotification, user *model.User, team *model.Team) *model.AppError {
+	channel := notification.channel
+	post := notification.post
+
 	if channel.IsGroupOrDirect() {
 		if result := <-a.Srv.Store.Team().GetTeamsByUserId(user.Id); result.Err != nil {
 			return result.Err
@@ -41,6 +44,7 @@ func (a *App) sendNotificationEmail(post *model.Post, user *model.User, channel
 			}
 		}
 	}
+
 	if *a.Config().EmailSettings.EnableEmailBatching {
 		var sendBatched bool
 		if result := <-a.Srv.Store.Preference().Get(user.Id, model.PREFERENCE_CATEGORY_NOTIFICATIONS, model.PREFERENCE_NAME_EMAIL_INTERVAL); result.Err != nil {
@@ -60,14 +64,25 @@ func (a *App) sendNotificationEmail(post *model.Post, user *model.User, channel
 		// fall back to sending a single email if we can't batch it for some reason
 	}
 
-	var useMilitaryTime bool
 	translateFunc := utils.GetUserTranslations(user.Locale)
-	if result := <-a.Srv.Store.Preference().Get(user.Id, model.PREFERENCE_CATEGORY_DISPLAY_SETTINGS, "use_military_time"); result.Err != nil {
+
+	var useMilitaryTime bool
+	if result := <-a.Srv.Store.Preference().Get(user.Id, model.PREFERENCE_CATEGORY_DISPLAY_SETTINGS, model.PREFERENCE_NAME_USE_MILITARY_TIME); result.Err != nil {
 		useMilitaryTime = true
 	} else {
 		useMilitaryTime = result.Data.(model.Preference).Value == "true"
 	}
 
+	var nameFormat string
+	if result := <-a.Srv.Store.Preference().Get(user.Id, model.PREFERENCE_CATEGORY_DISPLAY_SETTINGS, model.PREFERENCE_NAME_NAME_FORMAT); result.Err != nil {
+		nameFormat = *a.Config().TeamSettings.TeammateNameDisplay
+	} else {
+		nameFormat = result.Data.(model.Preference).Value
+	}
+
+	channelName := notification.GetChannelName(nameFormat, "")
+	senderName := notification.GetSenderName(nameFormat, a.Config().ServiceSettings.EnablePostUsernameOverride)
+
 	emailNotificationContentsType := model.EMAIL_NOTIFICATION_CONTENTS_FULL
 	if license := a.License(); license != nil && *license.Features.EmailNotificationContents {
 		emailNotificationContentsType = *a.Config().EmailSettings.EmailNotificationContentsType
@@ -79,7 +94,7 @@ func (a *App) sendNotificationEmail(post *model.Post, user *model.User, channel
 	} else if channel.Type == model.CHANNEL_GROUP {
 		subjectText = getGroupMessageNotificationEmailSubject(user, post, translateFunc, a.Config().TeamSettings.SiteName, channelName, emailNotificationContentsType, useMilitaryTime)
 	} else if *a.Config().EmailSettings.UseChannelInEmailNotifications {
-		subjectText = getNotificationEmailSubject(user, post, translateFunc, a.Config().TeamSettings.SiteName, team.DisplayName+" ("+channel.DisplayName+")", useMilitaryTime)
+		subjectText = getNotificationEmailSubject(user, post, translateFunc, a.Config().TeamSettings.SiteName, team.DisplayName+" ("+channelName+")", useMilitaryTime)
 	} else {
 		subjectText = getNotificationEmailSubject(user, post, translateFunc, a.Config().TeamSettings.SiteName, team.DisplayName, useMilitaryTime)
 	}
diff --git a/app/notification_push.go b/app/notification_push.go
index 517988a97..5c7df0da7 100644
--- a/app/notification_push.go
+++ b/app/notification_push.go
@@ -15,13 +15,23 @@ import (
 	"github.com/nicksnyder/go-i18n/i18n"
 )
 
-func (a *App) sendPushNotification(post *model.Post, user *model.User, channel *model.Channel, channelName string, sender *model.User, senderName string,
-	explicitMention, channelWideMention bool, replyToThreadType string) *model.AppError {
+func (a *App) sendPushNotification(notification *postNotification, user *model.User, explicitMention, channelWideMention bool, replyToThreadType string) *model.AppError {
+	channel := notification.channel
+	post := notification.post
+
 	cfg := a.Config()
-	contentsConfig := *cfg.EmailSettings.PushNotificationContents
-	teammateNameConfig := *cfg.TeamSettings.TeammateNameDisplay
+
+	var nameFormat string
+	if result := <-a.Srv.Store.Preference().Get(user.Id, model.PREFERENCE_CATEGORY_DISPLAY_SETTINGS, model.PREFERENCE_NAME_NAME_FORMAT); result.Err != nil {
+		nameFormat = *a.Config().TeamSettings.TeammateNameDisplay
+	} else {
+		nameFormat = result.Data.(model.Preference).Value
+	}
+
+	channelName := notification.GetChannelName(nameFormat, user.Id)
+	senderName := notification.GetSenderName(nameFormat, cfg.ServiceSettings.EnablePostUsernameOverride)
+
 	sessions, err := a.getMobileAppSessions(user.Id)
-	sentBySystem := senderName == utils.T("system.message.name")
 	if err != nil {
 		return err
 	}
@@ -43,25 +53,13 @@ func (a *App) sendPushNotification(post *model.Post, user *model.User, channel *
 	msg.RootId = post.RootId
 	msg.SenderId = post.UserId
 
-	if !sentBySystem {
-		senderName = sender.GetDisplayName(teammateNameConfig)
-		preference, prefError := a.GetPreferenceByCategoryAndNameForUser(user.Id, model.PREFERENCE_CATEGORY_DISPLAY_SETTINGS, "name_format")
-		if prefError == nil && preference.Value != teammateNameConfig {
-			senderName = sender.GetDisplayName(preference.Value)
-		}
-	}
-
-	if channel.Type == model.CHANNEL_DIRECT {
-		channelName = fmt.Sprintf("@%v", senderName)
-	}
-
+	contentsConfig := *cfg.EmailSettings.PushNotificationContents
 	if contentsConfig != model.GENERIC_NO_CHANNEL_NOTIFICATION || channel.Type == model.CHANNEL_DIRECT {
 		msg.ChannelName = channelName
 	}
 
 	if ou, ok := post.Props["override_username"].(string); ok && cfg.ServiceSettings.EnablePostUsernameOverride {
 		msg.OverrideUsername = ou
-		senderName = ou
 	}
 
 	if oi, ok := post.Props["override_icon_url"].(string); ok && cfg.ServiceSettings.EnablePostIconOverride {
diff --git a/app/notification_test.go b/app/notification_test.go
index bdc38e455..fa7bf7209 100644
--- a/app/notification_test.go
+++ b/app/notification_test.go
@@ -817,3 +817,165 @@ func TestGetMentionsEnabledFields(t *testing.T) {
 	assert.EqualValues(t, 4, len(mentionEnabledFields))
 	assert.EqualValues(t, expectedFields, mentionEnabledFields)
 }
+
+func TestPostNotificationGetChannelName(t *testing.T) {
+	sender := &model.User{Id: model.NewId(), Username: "sender", FirstName: "Sender", LastName: "Sender", Nickname: "Sender"}
+	recipient := &model.User{Id: model.NewId(), Username: "recipient", FirstName: "Recipient", LastName: "Recipient", Nickname: "Recipient"}
+	otherUser := &model.User{Id: model.NewId(), Username: "other", FirstName: "Other", LastName: "Other", Nickname: "Other"}
+	profileMap := map[string]*model.User{
+		sender.Id:    sender,
+		recipient.Id: recipient,
+		otherUser.Id: otherUser,
+	}
+
+	for name, testCase := range map[string]struct {
+		channel     *model.Channel
+		nameFormat  string
+		recipientId string
+		expected    string
+	}{
+		"regular channel": {
+			channel:  &model.Channel{Type: model.CHANNEL_OPEN, Name: "channel", DisplayName: "My Channel"},
+			expected: "My Channel",
+		},
+		"direct channel, unspecified": {
+			channel:  &model.Channel{Type: model.CHANNEL_DIRECT},
+			expected: "@sender",
+		},
+		"direct channel, username": {
+			channel:    &model.Channel{Type: model.CHANNEL_DIRECT},
+			nameFormat: model.SHOW_USERNAME,
+			expected:   "@sender",
+		},
+		"direct channel, full name": {
+			channel:    &model.Channel{Type: model.CHANNEL_DIRECT},
+			nameFormat: model.SHOW_FULLNAME,
+			expected:   "@Sender Sender",
+		},
+		"direct channel, nickname": {
+			channel:    &model.Channel{Type: model.CHANNEL_DIRECT},
+			nameFormat: model.SHOW_NICKNAME_FULLNAME,
+			expected:   "@Sender",
+		},
+		"group channel, unspecified": {
+			channel:  &model.Channel{Type: model.CHANNEL_GROUP},
+			expected: "other, sender",
+		},
+		"group channel, username": {
+			channel:    &model.Channel{Type: model.CHANNEL_GROUP},
+			nameFormat: model.SHOW_USERNAME,
+			expected:   "other, sender",
+		},
+		"group channel, full name": {
+			channel:    &model.Channel{Type: model.CHANNEL_GROUP},
+			nameFormat: model.SHOW_FULLNAME,
+			expected:   "Other Other, Sender Sender",
+		},
+		"group channel, nickname": {
+			channel:    &model.Channel{Type: model.CHANNEL_GROUP},
+			nameFormat: model.SHOW_NICKNAME_FULLNAME,
+			expected:   "Other, Sender",
+		},
+		"group channel, not excluding current user": {
+			channel:     &model.Channel{Type: model.CHANNEL_GROUP},
+			nameFormat:  model.SHOW_NICKNAME_FULLNAME,
+			expected:    "Other, Sender",
+			recipientId: "",
+		},
+	} {
+		t.Run(name, func(t *testing.T) {
+			notification := &postNotification{
+				channel:    testCase.channel,
+				sender:     sender,
+				profileMap: profileMap,
+			}
+
+			recipientId := recipient.Id
+			if testCase.recipientId != "" {
+				recipientId = testCase.recipientId
+			}
+
+			assert.Equal(t, testCase.expected, notification.GetChannelName(testCase.nameFormat, recipientId))
+		})
+	}
+}
+
+func TestPostNotificationGetSenderName(t *testing.T) {
+	th := Setup()
+	defer th.TearDown()
+
+	defaultChannel := &model.Channel{Type: model.CHANNEL_OPEN}
+	defaultPost := &model.Post{Props: model.StringInterface{}}
+	sender := &model.User{Id: model.NewId(), Username: "sender", FirstName: "Sender", LastName: "Sender", Nickname: "Sender"}
+
+	overriddenPost := &model.Post{
+		Props: model.StringInterface{
+			"override_username": "Overridden",
+			"from_webhook":      "true",
+		},
+	}
+
+	for name, testCase := range map[string]struct {
+		channel        *model.Channel
+		post           *model.Post
+		nameFormat     string
+		allowOverrides bool
+		expected       string
+	}{
+		"name format unspecified": {
+			expected: sender.Username,
+		},
+		"name format username": {
+			nameFormat: model.SHOW_USERNAME,
+			expected:   sender.Username,
+		},
+		"name format full name": {
+			nameFormat: model.SHOW_FULLNAME,
+			expected:   sender.FirstName + " " + sender.LastName,
+		},
+		"name format nickname": {
+			nameFormat: model.SHOW_NICKNAME_FULLNAME,
+			expected:   sender.Nickname,
+		},
+		"system message": {
+			post:     &model.Post{Type: model.POST_SYSTEM_MESSAGE_PREFIX + "custom"},
+			expected: utils.T("system.message.name"),
+		},
+		"overridden username": {
+			post:           overriddenPost,
+			allowOverrides: true,
+			expected:       overriddenPost.Props["override_username"].(string),
+		},
+		"overridden username, direct channel": {
+			channel:        &model.Channel{Type: model.CHANNEL_DIRECT},
+			post:           overriddenPost,
+			allowOverrides: true,
+			expected:       sender.Username,
+		},
+		"overridden username, overrides disabled": {
+			post:           overriddenPost,
+			allowOverrides: false,
+			expected:       sender.Username,
+		},
+	} {
+		t.Run(name, func(t *testing.T) {
+			channel := defaultChannel
+			if testCase.channel != nil {
+				channel = testCase.channel
+			}
+
+			post := defaultPost
+			if testCase.post != nil {
+				post = testCase.post
+			}
+
+			notification := &postNotification{
+				channel: channel,
+				post:    post,
+				sender:  sender,
+			}
+
+			assert.Equal(t, testCase.expected, notification.GetSenderName(testCase.nameFormat, testCase.allowOverrides))
+		})
+	}
+}
diff --git a/model/preference.go b/model/preference.go
index c7639db96..6f13c38e5 100644
--- a/model/preference.go
+++ b/model/preference.go
@@ -21,7 +21,11 @@ const (
 	PREFERENCE_CATEGORY_SIDEBAR_SETTINGS    = "sidebar_settings"
 
 	PREFERENCE_CATEGORY_DISPLAY_SETTINGS = "display_settings"
+	PREFERENCE_NAME_CHANNEL_DISPLAY_MODE = "channel_display_mode"
 	PREFERENCE_NAME_COLLAPSE_SETTING     = "collapse_previews"
+	PREFERENCE_NAME_MESSAGE_DISPLAY      = "message_display"
+	PREFERENCE_NAME_NAME_FORMAT          = "name_format"
+	PREFERENCE_NAME_USE_MILITARY_TIME    = "use_military_time"
 
 	PREFERENCE_CATEGORY_THEME = "theme"
 	// the name for theme props is the team id