Issue 2440 - implement Source.get_cache_dir() to be used by custom filters/globals

cms/converters.py

 # coding: utf-8
 
 # This file is part of the Adblock Plus web scripts,
 # Copyright (C) 2006-2015 Eyeo GmbH
 #
 # Adblock Plus is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License version 3 as
 # published by the Free Software Foundation.
 #
 # Adblock Plus is distributed in the hope that it will be useful,
@@ skipping 290 matching lines @@
       "translate": self.translate,
       "linkify": self.linkify,
       "toclist": self.toclist,
     }
 
     globals = {
       "get_string": self.get_string,
       "get_page_content": self.get_page_content,
     }
 
+    source = self._params["source"]
     self._module_refs = []
     for dirname, dictionary in [("filters", filters), ("globals", globals)]:
-      for filename in self._params["source"].list_files(dirname):
+      for filename in source.list_files(dirname):
         root, ext = os.path.splitext(filename)
         if ext.lower() != ".py":
           continue
 
         path = "%s/%s" % (dirname, filename)
-        code = self._params["source"].read_file(path)
+        code = source.read_file(path)
         module = imp.new_module(root.replace("/", "."))
+        if hasattr(source, "get_cache_dir"):
+          module.CMS_CACHE_DIR = source.get_cache_dir()
         exec code in module.__dict__
 
         name = os.path.basename(root)
         if not hasattr(module, name):
           raise Exception("Expected symbol %s not found in %s file %s" % (name, dirname, filename))
         dictionary[name] = getattr(module, name)
 
         # HACK: The module we created here can be garbage collected because it
         # isn't added to sys.modules. If a function is called and its module is
         # gone it might cause weird errors (imports and module variables
@@ skipping 62 matching lines @@
         stack.pop()
       stack[-1]["subitems"].append(item)
       stack.append(item)
     return structured
 
 converters = {
   "html": RawConverter,
   "md": MarkdownConverter,
   "tmpl": TemplateConverter,
 }