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Patching Rails - Rendering form partials

by damian on January 16, 2008

Yesterday we got a patch committed to Rails. This new enhancement provides a nicer and more conventional way of rendering form fields as a partial.

Instead of writing this not-so-DRY call to

   1  render

  <% form_for(@client) do |f| %>
    <%= render :partial => 'form', :locals => {:f => f} %>
    <%= submit_tag 'Create' %>
  <% end %>

... we can do something cleaner, like this:

  <% form_for(@client) do |f| %>
    <%= render :partial => f %>
    <%= submit_tag 'Create' %>
  <% end %>

Here, the rendered partial is

   1  clients/_form

   1  form

If we used a different form builder,

  <% form_for(@client, :builder => LabellingFormBuilder) do |f| %>
    <%= render :partial => f %>
    <%= submit_tag 'Create' %>
  <% end %>

... the partial that gets rendered is

   1  clients/_labelling_form

   1  labelling_form

There have been other proposals, but in the end we agreed that the

   1  render

   1  render :partial => @clients

The patch also changes the docs and provides unit tests for the new behavior.