From d9ff5bac32ac4e03d38876e04f96ba826b68d0ba Mon Sep 17 00:00:00 2001
From: Magnun Leno <magnun@codecommunity.org>
Date: Tue, 14 Jan 2014 00:41:48 -0200
Subject: [PATCH] Adds support for themes functions

With this changes the themes can have (not obligatory) a functions.py
file bundled with the templates. The purpose of this file is to hold
helper functions to be injected into the jinja2 templates. To control
which functions will be injected is specified the __export__ list. A
sample was inserted in pelican/themes/simple/templates/functions.py.
---
 pelican/generators.py                        | 9 +++++++++
 pelican/themes/simple/templates/functions.py | 9 +++++++++
 2 files changed, 18 insertions(+)
 create mode 100644 pelican/themes/simple/templates/functions.py

diff --git a/pelican/generators.py b/pelican/generators.py
index b7612fa2..f8be3827 100644
--- a/pelican/generators.py
+++ b/pelican/generators.py
@@ -2,6 +2,7 @@
 from __future__ import unicode_literals, print_function
 
 import os
+import imp
 import math
 import random
 import logging
@@ -62,6 +63,14 @@ class Generator(object):
             ]),
             extensions=self.settings['JINJA_EXTENSIONS'],
         )
+        try:
+            theme_functions = imp.load_source('theme_functions', self._templates_path[0]+'/functions.py')
+        except IOError:
+            theme_functions = None
+
+        if theme_functions and '__export__' in vars(theme_functions):
+            for func_name in theme_functions.__export__:
+                self.env.globals[func_name] = getattr(theme_functions, func_name)
 
         logger.debug('template list: {0}'.format(self.env.list_templates()))
 
diff --git a/pelican/themes/simple/templates/functions.py b/pelican/themes/simple/templates/functions.py
new file mode 100644
index 00000000..de40bd78
--- /dev/null
+++ b/pelican/themes/simple/templates/functions.py
@@ -0,0 +1,9 @@
+# encoding: utf-8
+
+__export__ = ["helperFunction"]
+
+def helperFunction():
+    return "<p>I'm from a helper function!</p>"
+
+def anotherHelper():
+    return "I'm not being exported!"