Upgrading from 2.0.0.rc1 to latest (2.3.1) breaks Lookbook previews when rendering partials inside a component

[bryanadvisory]

With the new render(partial...)) syntax, we get a undefined method 'render' for nil

I tracked down the issue and it seems to come from phlex-rails-2.3.1/lib/phlex/rails/sgml.rb:94 that does not resolve a capture_context, so it breaks when calling render.

This is how the partial is being rendered inside the component itself with the new syntax:

render(partial("shared/form_errors", object: @form.object))

Any support would be appreciated!

[joeldrapper]

Interesting. I wonder how Lookbook is calling Phlex. It may need to be updated to use the render_in interface, passing a view context.

[bryanadvisory]

Ok, so it seems like there are some hard constraints on Lookbook side for the view_component gem, since after trying many things, extending these previews from ViewComponent::Preview instead of Lookbook::Preview seems to solved the issue. Just in case anybody stumbles upon this issue in the future. This should only apply for rendering partials inside the components and some other weirdness that makes raw html output show up on previews.