[MM-27535] User invite limits for MM Cloud (#15197)

* Add a config for MM User Limit

* Adding graceful errors for if an administrator invites people passed their user limit

* Including changed vendor files

* Adding unit test

* Fix a bug

* Push up working tests (Thanks Joram)

* Add more cases, clean up logs in code

* One more case

* Refactoring based on PR comments

* Updating i18n

* Some changes based on PR review

* Remove a comment

* Bring back some translations that were somehow removed

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

api4/team_test.go

@@ -2721,6 +2721,69 @@ func TestImportTeam(t *testing.T) {
 	})
 }
 
+func TestInviteUsersToTeamWithUserLimit(t *testing.T) {
+	th := Setup(t).InitBasic()
+	defer th.TearDown()
+	email1 := th.GenerateTestEmail()
+	email2 := th.GenerateTestEmail()
+	email3 := th.GenerateTestEmail()
+	th.App.UpdateConfig(func(cfg *model.Config) {
+		*cfg.ServiceSettings.EnableEmailInvitations = true
+		*cfg.ExperimentalSettings.CloudUserLimit = 2
+	})
+
+	t.Run("System admin, invite when at limit should fail", func(t *testing.T) {
+		invitesWithErrors, resp := th.SystemAdminClient.InviteUsersToTeamGracefully(th.BasicTeam.Id, []string{email1, email2})
+		CheckNoError(t, resp)
+		require.Len(t, invitesWithErrors, 2)
+		require.NotNil(t, invitesWithErrors[0].Error)
+		assert.Equal(t, invitesWithErrors[0].Error.Message, "You've reached the user limit of your current tier")
+		require.NotNil(t, invitesWithErrors[1].Error)
+		assert.Equal(t, invitesWithErrors[1].Error.Message, "You've reached the user limit of your current tier")
+	})
+
+	t.Run("Regular user, invite when at limit should succeed", func(t *testing.T) {
+		invitesWithErrors, resp := th.Client.InviteUsersToTeamGracefully(th.BasicTeam.Id, []string{email3})
+		CheckNoError(t, resp)
+		require.Len(t, invitesWithErrors, 1)
+		assert.Nil(t, invitesWithErrors[0].Error)
+
+	})
+
+	th.App.UpdateConfig(func(cfg *model.Config) {
+		*cfg.ExperimentalSettings.CloudUserLimit = 5
+	})
+
+	t.Run("With one remaining user inviting more than one user as admin invites only one user", func(t *testing.T) {
+		invitesWithErrors, resp := th.SystemAdminClient.InviteUsersToTeamGracefully(th.BasicTeam.Id, []string{email1, email2})
+		CheckNoError(t, resp)
+		require.Len(t, invitesWithErrors, 2)
+		require.Nil(t, invitesWithErrors[0].Error)
+		require.NotNil(t, invitesWithErrors[1].Error)
+		assert.Equal(t, invitesWithErrors[1].Error.Message, "You've reached the user limit of your current tier")
+
+	})
+
+	t.Run("With one remaining user inviting more than one user as a regular user sends all invites", func(t *testing.T) {
+		invitesWithErrors, resp := th.Client.InviteUsersToTeamGracefully(th.BasicTeam.Id, []string{email1, email2})
+		CheckNoError(t, resp)
+		require.Len(t, invitesWithErrors, 2)
+		assert.Nil(t, invitesWithErrors[0].Error)
+		assert.Nil(t, invitesWithErrors[1].Error)
+
+	})
+
+	th.App.UpdateConfig(func(cfg *model.Config) {
+		*cfg.ExperimentalSettings.CloudUserLimit = 100
+	})
+	t.Run("Invited user count is well below limit", func(t *testing.T) {
+		invitesWithErrors, resp := th.SystemAdminClient.InviteUsersToTeamGracefully(th.BasicTeam.Id, []string{email1, email2})
+		CheckNoError(t, resp)
+		require.Len(t, invitesWithErrors, 2)
+		require.Nil(t, invitesWithErrors[0].Error)
+	})
+}
+
 func TestInviteUsersToTeam(t *testing.T) {
 	th := Setup(t).InitBasic()
 	defer th.TearDown()