# HG changeset patch
# User Franz Glasner <f.glasner@feldmann-mg.com>
# Date 1457623485 -3600
# Node ID baf862cb48604d08e5fbedd54f3516dec5bb5f7b
# Parent  fa65adab0b717af56ecdda3fd99d91b5ecde3ced
Handle "None" variable values when substituting

diff -r fa65adab0b71 -r baf862cb4860 configmix/config.py
--- a/configmix/config.py	Thu Mar 10 16:18:41 2016 +0100
+++ b/configmix/config.py	Thu Mar 10 16:24:45 2016 +0100
@@ -154,6 +154,8 @@
                 return s
             varname, filters = self._split_filters(s[start+2:end])
             varvalue = self._apply_filters(filters, self.getvar_s(varname))
+            if varvalue is None:
+                varvalue = u("")
             replaced = u(b"{0}{1}").format(s[:start], varvalue)
             s = u(b"{0}{1}").format(replaced, s[end+2:])
             # don't re-evaluate because `self.getvar_s()` expands already