[SOLVED] Why does this simple_fields

Why does this simple_fields_for not execute?

I have two models:

class PortStock < ApplicationRecord
  has_many :closed_positions
  accepts_nested_attributes_for :closed_positions
end

class ClosedPosition < ApplicationRecord
  belongs_to :closer, class_name: "PortStock", foreign_key: "closer_id"
  belongs_to :closed, class_name: "PortStock", foreign_key: "port_stock_id" 
end

I know this association works, because I have tested it otherwise.

I then have a form partial at views/port_stocks/sell/_form.html.erb that looks like this:

<%= simple_form_for @port_stock, url: port_stocks_sell_order_path, method: :post do |f| %>
   <% @port_stocks.each do |port_stock| %>
       <%= f.simple_fields_for :closed_positions, html: { class: "form-inline" } do |c| %>
          <%= c.input_field :num_units, id: "sell-ps-#{port_stock.id}", class: "form-control mx-sm-3" %>
       <% end %>
   <% end %>
  <%= f.button :submit, "Sell Stock", class:"btn btn-primary" %>
<% end %>

But, when the HTML is rendered, it doesn't render any of the text fields within the simple_fields_for.

If I put a binding.pry right before the f.simple_fields_for line, it halts execution. If I put it right after, it doesn't. That tells me that the simple_fields_for isn't being executed.

But per the docs that's how I should do it.

What am I missing? Why does this not render the form fields within the simple_fields_for?

Solution

I figured it out.

I didn't actually build the closed_positions in my controller.

So once I added this code to my controller:

@port_stock.closed_positions.build

That worked like a charm.