Be explicit about the things you send from your Rails controller to the view.

app/controllers/application_controller.rb:

class ApplicationController
  include RenderWithView
end

app/controllers/home_controller.rb:

class HomeController < ApplicationController
  def index
    render_with_view posts: Post.all
  end
end

app/views/home/index.html.erb:

<ul>
  <% view.posts.each do |post| %>
    <li><%= link_to post.title, post %></li>
  <% end %>
</ul>

They feel like magic. Instead I like how this forces me to be explicit in what I send along to my templates. It's like a small step towards having a presenter/view layer (or whatever) but not going further than just adding the convention of using a single variable.

An object with reader methods for every key in the hash you gave it. A HalfOpenStruct in a way.

Add render_with_view to your Gemfile:

gem 'render_with_view'

Include it in your ApplicationController:

class ApplicationController
  include RenderWithView
end

require 'render_with_view/rspec_matcher'

describe ThingController do
  subject { get :index }
  it { should set_view_local :key, optional_value }
end

MIT