Users: fix UserMenu.cshtml for anonymous visitors and without the Avatar feature

[DavidHolmlabs]

OrchardCoreContrib.Users' UserMenu.cshtml override breaks every page that renders the user menu (e.g. TheTheme's navbar, including the login page) in two cases. Both reproduce on 1.7.0 and on current main.

1. Anonymous visitors (Avatar enabled)

The view has no User.Identity.IsAuthenticated check. For a logged-out visitor it builds an avatar from a null User.Identity.Name:

ArgumentNullException: Value cannot be null. (Parameter 'DisplayName')

Fix: for anonymous visitors, render the same markup as the stock OrchardCore.Users UserMenu.cshtml (its anonymous dropdown, or a login link).

2. Any Users feature enabled without Avatar (e.g. only Impersonation)

Orchard Core binds a module's shape templates to every enabled feature of that module (ShapeTemplateBindingStrategy), so this view is active whenever any OrchardCoreContrib.Users feature is. The @attribute [Feature("OrchardCoreContrib.Users.Avatar")] doesn't prevent that. Without the Avatar feature, and with a host that doesn't call AddOrchardCoreContrib(), nothing registers IAvatarService:

InvalidOperationException: No service for type 'OrchardCoreContrib.Avatars.IAvatarService' has been registered.

Fix: resolve IAvatarService optionally. If there is none, or it returns an empty avatar (NullAvatarService), show a user icon in place of the <img>. Otherwise the dropdown is unchanged.

Verification

I booted OrchardCoreContrib.Modules.Web from the SaaS recipe (TheTheme) with WebApplicationFactory and requested /. I removed the host-level NullAvatarService registration in Program.cs, so the host behaves like a consumer app that doesn't call AddOrchardCoreContrib().

Features enabled	Visitor	Before	After
Avatar	anonymous	throws ArgumentNullException	200, login link
Avatar	logged in	200, avatar dropdown	200, avatar dropdown
Impersonation	anonymous	throws No service for type 'IAvatarService'	200, login link
Impersonation	logged in	throws (the login page itself fails)	200, dropdown with user icon
Impersonation + Avatar	anonymous	—	200, login link
Impersonation + Avatar	logged in	—	200, avatar dropdown

The Profile / Change password links resolve the same before and after.

Downstream we currently work around both bugs with a view override in our own module, which we'd like to delete once this is released.

🤖 Generated with Claude Code

[hishamco]

Thanks @DavidHolmlabs I will check your changes and hope to merge ASAP

One more thing: please provide the steps to reproduce for the first case, coz I presume it should show the menu after you're logged in