Add 'sample' Liquid filter

Equivalent to Array#sample functionality

lib/jekyll/filters.rb

@@ -281,6 +281,11 @@ module Jekyll
       new_ary
     end
 
+    def sample(input)
+      return input unless input.respond_to?(:sample)
+      input.sample(1)
+    end
+
     # Convert an object into its String representation for debugging
     #
     # input - The Object to be converted

site/_docs/templates.md

@@ -246,6 +246,17 @@ common tasks easier.
         </p>
       </td>
     </tr>
+    <tr>
+      <td>
+        <p class="name"><strong>Sample</strong></p>
+        <p>Pick a random value from an array.</p>
+      </td>
+      <td class="align-center">
+        <p>
+         <code class="filter">{% raw %}{{ site.pages | sample }}{% endraw %}</code>
+        </p>
+      </td>
+    </tr>
   </tbody>
 </table>
 </div>

test/test_filters.rb

@@ -388,5 +388,12 @@ class TestFilters < JekyllUnitTest
       end
     end
 
+    context "sample filter" do
+      should "return a random item from the array" do
+        input = %w(hey there bernie)
+        assert_includes input, @filter.sample(input)
+      end
+    end
+
   end
 end