Module: Kaseifu::ActionView::Helpers::RenderingHelper

Included in:
Kaseifu::ActionView::Helpers
Defined in:
lib/kaseifu/action_view/helpers/rendering_helper.rb

Instance Method Summary collapse

Instance Method Details

#render_if_present(method, in: nil, as: nil, **options) ⇒ Object

Render partial if the given method is present as the receiver’s method.

For example, something like

<%= render_if_present :shop_image_path, in: @shop %>

same as

<% if @shop.shop_image_path.present? %>
  <%= render 'shop_image_path', locals: { shop_image_path: @shop.shop_image_path } %>
<% end %>

You can pass different path of partial

<%= render_if_present :shop_image_path, in: @shop, partial: 'image' %>

same as

<% if @shop.shop_image_path.present? %>
  <%= render 'image', locals: { shop_image_path: @shop.shop_image_path } %>
<% end %>

You can use different name as a local variable name in the partial

<%= render_if_present :shop_image_path, in: @shop, as: :shop_image %>

same as

<% if @shop.shop_image_path.present? %>
  <%= render 'shop_image', locals: { shop_image: @shop.shop_image_path } %>
<% end %>

You can pass more locals

<%= render_if_present :shop_image_path, in: @shop, locals: { shop_name: @shop.name } %>

same as

<% if @shop.shop_image_path.present? %>
  <%= render 'shop_image_path', locals: { shop_image_path: @shop.shop_image_path, shop_name: @shop.name } %>
<% end %>



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# File 'lib/kaseifu/action_view/helpers/rendering_helper.rb', line 32

def render_if_present(method, in: nil, as: nil, **options)
  # "in" is special keyword so need to use local_variable_get to get value
  receiver = binding.local_variable_get(:in)

  fail ArgumentError, 'missing keyword: in' if receiver.nil?

  # If receiver doesn't respond to the given method, render nothing
  return '' unless receiver.respond_to?(method)

  key = (as || method).to_sym
  value = receiver.send(method)

  # If given method return blank, render nothing
  return '' if value.blank?

  # If partial file name is already exist use it else use key.
  options[:partial] ||= key.to_s

  options[:locals] ||= {}
  options[:locals].merge!(key => value)

  render options
end