poder ocultar campos por defecto

app/models/post.rb

@@ -22,7 +22,7 @@ class Post
   # datos que no tienen que terminar en el front matter
   REJECT_FROM_FRONT_MATTER = %w[date slug draft ext].freeze
   # datos que no traemos del template
-  REJECT_FROM_TEMPLATE = %w[has_content date draft categories layout title ext tags date slug].freeze
+  REJECT_FROM_TEMPLATE = %w[draft categories layout title ext tags date slug].freeze
   DEFAULT_PARAMS = [:title, :date, :content, :slug, :cover,
       :layout, :permalink, :dir,
       { lang: {} }, { tags: [] }, { categories: [] }]
@@ -187,7 +187,11 @@ class Post
 
   # Determina si el post lleva contenido o es solo front_matter
   def content?
-    template && template.fetch_front_matter('has_content', true)
+    has_field? :content
+  end
+
+  def has_field?(field)
+    template && template.fetch_front_matter("has_#{field.to_s}", true)
   end
 
   # imita Model.update_attributes de ActiveRecord
@@ -300,6 +304,7 @@ class Post
     return [] unless template
     @template_fields ||= template.front_matter.map do |key, contents|
       next if REJECT_FROM_TEMPLATE.include? key
+      next if key.start_with? 'has_'
 
       Post::TemplateField.new(self, key, contents)
     end.compact

app/views/posts/_form.haml

@@ -35,44 +35,50 @@
         t('help.preview_html') ]
       = text_area_tag 'post[content]', @post.content, autofocus: true,
         class: 'post-content'
-  .form-group
-    = label_tag 'post_date', t('posts.date')
-    = date_field 'post', 'date', value: @post.date.try(:strftime, '%F'),
-      class: 'form-control'
-    %small.text-muted.form-text= t('posts.date_help')
-  .form-group
-    = render 'layouts/help', help: t('help.autocomplete_html')
-    = label_tag 'post_categories', t('posts.categories')
-    = select_tag 'post[categories][]',
-      options_for_select(@site.categories(lang: @lang), @post.categories),
-      { class: 'form-control select2', multiple: 'multiple',
-        data: { tags: true,
-        placeholder: t('posts.select.placeholder'),
-        'allow-clear': true } }
-  .form-group
-    = label_tag 'post_tags', t('posts.tags')
-    = select_tag 'post[tags][]',
-      options_for_select(@site.tags(lang: @lang), @post.tags),
-      { class: 'form-control select2', multiple: 'multiple',
-        data: { tags: true,
-        placeholder: t('posts.select.placeholder'),
-        'allow-clear': true } }
-  .form-group
-    = label_tag 'post_slug', t('posts.slug')
-    = text_field 'post', 'slug', value: @post.slug,
-      class: 'form-control'
-    %small.text-muted.form-text= t('posts.slug_help')
-  .form-group
-    = label_tag 'post_permalink', t('posts.permalink')
-    = text_field 'post', 'permalink', value: @post.get_front_matter('permalink'),
-      class: 'form-control'
-    %small.text-muted.form-text= t('posts.permalink_help')
-  .form-group
-    = label_tag 'post_layout', t('posts.layout')
-    = select_tag 'post[layout]',
-      options_for_select(@site.layouts, @post.get_front_matter('layout')),
-      { class: 'form-control select2' }
-    %small.text-muted.form-text= t('posts.layout_help')
+  - if @post.has_field? :date
+    .form-group
+      = label_tag 'post_date', t('posts.date')
+      = date_field 'post', 'date', value: @post.date.try(:strftime, '%F'),
+        class: 'form-control'
+      %small.text-muted.form-text= t('posts.date_help')
+  = render 'layouts/help', help: t('help.autocomplete_html')
+  - if @post.has_field? :categories
+    .form-group
+      = label_tag 'post_categories', t('posts.categories')
+      = select_tag 'post[categories][]',
+        options_for_select(@site.categories(lang: @lang), @post.categories),
+        { class: 'form-control select2', multiple: 'multiple',
+          data: { tags: true,
+          placeholder: t('posts.select.placeholder'),
+          'allow-clear': true } }
+  - if @post.has_field? :tags
+    .form-group
+      = label_tag 'post_tags', t('posts.tags')
+      = select_tag 'post[tags][]',
+        options_for_select(@site.tags(lang: @lang), @post.tags),
+        { class: 'form-control select2', multiple: 'multiple',
+          data: { tags: true,
+          placeholder: t('posts.select.placeholder'),
+          'allow-clear': true } }
+  - if @post.has_field? :slug
+    .form-group
+      = label_tag 'post_slug', t('posts.slug')
+      = text_field 'post', 'slug', value: @post.slug,
+        class: 'form-control'
+      %small.text-muted.form-text= t('posts.slug_help')
+  - if @post.has_field? :permalink
+    .form-group
+      = label_tag 'post_permalink', t('posts.permalink')
+      = text_field 'post', 'permalink', value: @post.get_front_matter('permalink'),
+        class: 'form-control'
+      %small.text-muted.form-text= t('posts.permalink_help')
+  - if @post.has_field? :layout
+    .form-group
+      = label_tag 'post_layout', t('posts.layout')
+      = select_tag 'post[layout]',
+        options_for_select(@site.layouts, @post.get_front_matter('layout')),
+        { class: 'form-control select2' }
+      %small.text-muted.form-text= t('posts.layout_help')
   - if @site.i18n?
     - @site.translations.each do |lang|
       - next if lang == @lang