Awesome, thank you! The logic hasn’t gotten quite complex. I can probably simplify it a bit but I’m trying to cover some different known styles I’ve seen. One thing that can’t be supported (and doesn’t appear to be supported in regular html formatting) is self-closing tags without the />. I’m also not bothering with extra weird stuff that I never see that is still valid HTML (like having whitespace between between the opening brace and the tag name (< p>, for example).

I’m trying to support both these styles for eex and Surface:

| represents the cursor after a new line.

<%= live_component @socket,
   Component,
   id: "id",
   foo: "foo" %>
|

<%= live_component @socket,
   Component,
   id: "id",
   foo: "foo"
%>
|

<%= live_component @socket,
   Component,
   id: "id",
   foo: "foo" do %>
  |
<% end %>

<%= live_component @socket,
   Component,
   id: "id",
   foo: "foo" do
%>
  |
<% end %>

<Component
  foo="foo" />
|

<Component
  foo="foo"
/>
|

I’m not sure if anyone does anything else but I’d be interested to know.