python: Ensure that we pass utf-8 encoded string to libnotmuch

If we use unicode objects, libnotmuch would not cope with null bytes in
the byte array, so we need to make sure they are nicely formatted as
utf-8.

Introduce a helper function _str which does this throughout the code.

Patch slightly modified by Sebastian Spaeth.

Signed-off-by: Sebastian Spaeth <Sebastian@SSpaeth.de>

1 files changed, 12 insertions, 0 deletions

diff --git a/bindings/python/notmuch/globals.py b/bindings/python/notmuch/globals.py
index 77f2905b..05b9962a 100644
--- a/bindings/python/notmuch/globals.py
+++ b/bindings/python/notmuch/globals.py
@@ -98,3 +98,15 @@ class NotmuchError(Exception):
             return self.args[0]
         else:
             return STATUS.status2str(self.args[1])
+
+def _str(value):
+    """Ensure a nicely utf-8 encoded string to pass to libnotmuch
+
+    C++ code expects strings to be well formatted and
+    unicode strings to have no null bytes."""
+    if not isinstance(value, basestring):
+        raise TypeError("Expected str or unicode, got %s" % str(type(value)))
+    if isinstance(value, unicode):
+        return value.encode('UTF-8')
+    return value
+