View Components for /admin

[joemasilotti]

This PR is my first deep dive into generic, styled, reusable View Components. The codebase already has a fair amount of existing ones. But they weren't built in a way that makes them easily reusable.

The ones introduced in this PR are more generic to specific use-cases: styled tables in an admin context. I'm using this as a pressure test to see how I could add more components like these to the rest of the app.

Notes and thoughts

• app/views/admin/users/index.html.erb looks real clean now!
• Using #call directly in the .rb file of a component for simple layout cleans up the code quite a bit. There's no additional .html.erb file!
• Working inside-out seemed to work better (in this example) than outside-in. Working outside-in made it a bit harder to conceptualize how the components played together.
• I'm not sold on passing "first" into components to style them differently. Ideally, that could be handled by the parent component. But I haven't figured out how to do that yet.
  • I restyled the table headers a bit so the concept of "first" no longer exists.
• I punted on anything related to Action View Form Helpers. There doesn't seem to be a good way to integrate these helpers with View Component (yet), so I opted to ignore them for now.
  • I went ahead and injected the Rails form object directly into the View Components. I understand that this tightly couples them, but it feels like an OK trade-off for now. I still get to use all the nice Rails helpers we all know and love.
• title || content is a nice shortcut to be able to pass in a string or a block to render more custom content in a component.
• render TableComponent.new do |table| over render TableComponent.new do |component| - makes it easier to understand which component you are chaining off of when nested.