[MM-41815] Fix custom status not handling update user errors (#19588)

Co-authored-by: Mattermod <mattermod@users.noreply.github.com>

app/status.go

@@ -418,7 +418,7 @@ func (a *App) SetCustomStatus(userID string, cs *model.CustomStatus) *model.AppE
 	user.SetCustomStatus(cs)
 	_, updateErr := a.UpdateUser(user, true)
 	if updateErr != nil {
-		return err
+		return updateErr
 	}
 
 	if err := a.addRecentCustomStatus(userID, cs); err != nil {
@@ -437,7 +437,7 @@ func (a *App) RemoveCustomStatus(userID string) *model.AppError {
 	user.ClearCustomStatus()
 	_, updateErr := a.UpdateUser(user, true)
 	if updateErr != nil {
-		return err
+		return updateErr
 	}
 
 	return nil

app/status_test.go

@@ -6,9 +6,13 @@ package app
 import (
 	"testing"
 
+	"github.com/stretchr/testify/mock"
 	"github.com/stretchr/testify/require"
 
+	"github.com/mattermost/mattermost-server/v6/app/users"
 	"github.com/mattermost/mattermost-server/v6/model"
+	"github.com/mattermost/mattermost-server/v6/store"
+	"github.com/mattermost/mattermost-server/v6/store/storetest/mocks"
 )
 
 func TestSaveStatus(t *testing.T) {
@@ -64,3 +68,62 @@ func TestCustomStatus(t *testing.T) {
 	require.Nil(t, err, "failed to get custom status after clear %v", err)
 	require.Equal(t, csClear, csSaved)
 }
+
+func TestCustomStatusErrors(t *testing.T) {
+
+	fakeUserID := "foobar"
+	mockErr := store.NewErrNotFound("User", fakeUserID)
+	mockUser := &model.User{Id: fakeUserID}
+
+	tests := map[string]struct {
+		customStatus string
+		successFn    string
+		failFn       string
+		expectedErr  string
+	}{
+		"set custom status fails on get user":       {customStatus: "set", successFn: "Update", failFn: "Get", expectedErr: MissingAccountError},
+		"set custom status fails on update user":    {customStatus: "set", successFn: "Get", failFn: "Update", expectedErr: "app.user.update.finding.app_error"},
+		"remove custom status fails on get user":    {customStatus: "remove", successFn: "Update", failFn: "Get", expectedErr: MissingAccountError},
+		"remove custom status fails on update user": {customStatus: "remove", successFn: "Get", failFn: "Update", expectedErr: "app.user.update.finding.app_error"},
+	}
+
+	for name, tc := range tests {
+		t.Run(name, func(t *testing.T) {
+			th := SetupWithStoreMock(t)
+			defer th.TearDown()
+
+			mockUserStore := mocks.UserStore{}
+
+			mockUserStore.On(tc.successFn, mock.Anything, mock.Anything).Return(mockUser, nil)
+			mockUserStore.On(tc.failFn, mock.Anything, mock.Anything).Return(nil, mockErr)
+
+			var err error
+			mockSessionStore := mocks.SessionStore{}
+			mockOAuthStore := mocks.OAuthStore{}
+			th.App.ch.srv.userService, err = users.New(users.ServiceConfig{
+				UserStore:    &mockUserStore,
+				SessionStore: &mockSessionStore,
+				OAuthStore:   &mockOAuthStore,
+				ConfigFn:     th.App.ch.srv.Config,
+				LicenseFn:    th.App.ch.srv.License,
+			})
+			require.NoError(t, err)
+
+			cs := &model.CustomStatus{
+				Emoji: ":smile:",
+				Text:  "honk!",
+			}
+
+			var appErr *model.AppError
+			switch tc.customStatus {
+			case "set":
+				appErr = th.App.SetCustomStatus(fakeUserID, cs)
+			case "remove":
+				appErr = th.App.RemoveCustomStatus(fakeUserID)
+			}
+
+			require.NotNil(t, appErr)
+			require.Equal(t, tc.expectedErr, appErr.Id)
+		})
+	}
+}