add symlink failing test

Signed-off-by: Parker Moore <parkrmoore@gmail.com>

test/source/_includes/about.html

@@ -0,0 +1 @@
+../about.html

test/source/about.html

@@ -1,6 +0,0 @@
----
-title: About
-permalink: /about/
----
-
-About the site

test/source/about.html

@@ -0,0 +1 @@
+/tmp/pages-test

test/test_tags.rb

@@ -363,6 +363,27 @@ CONTENT
   end
 
   context "include tag with parameters" do
+
+    context "with symlink'd include" do
+
+      setup do
+        content = <<CONTENT
+---
+title: Include symlink
+---
+
+{% include about.html %}
+
+CONTENT
+        create_post(content, {'permalink' => 'pretty', 'source' => source_dir, 'destination' => dest_dir, 'read_posts' => true})
+      end
+
+      should "not allow symlink includes" do
+        File.open("/tmp/pages-test", 'w') { |file| file.write("SYMLINK TEST") }
+        assert_no_match /SYMLINK TEST/, @result
+      end
+    end
+
     context "with one parameter" do
       setup do
         content = <<CONTENT