More merging adjustments.

Looks like this should be in pretty good shape and has passed some
of the basic backwards compat. merging tests that I added.

1 files changed, 44 insertions, 0 deletions

diff --git a/cloudinit/mergers/m_str.py b/cloudinit/mergers/m_str.py
new file mode 100644
index 00000000..e22ce28a
--- /dev/null
+++ b/cloudinit/mergers/m_str.py
@@ -0,0 +1,44 @@
+# -*- coding: utf-8 -*-
+# vi: ts=4 expandtab
+#
+# Copyright (C) 2012 Yahoo! Inc.
+#
+# Author: Joshua Harlow <harlowja@yahoo-inc.com>
+#
+# This program 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.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program. If not, see <http://www.gnu.org/licenses/>.
+
+
+class Merger(object):
+    def __init__(self, _merger, opts):
+        self._append = 'append' in opts
+
+    def __str__(self):
+        return 'StringMerger: (append=%s)' % (self._append)
+
+    # On encountering a unicode object to merge value with
+    # we will for now just proxy into the string method to let it handle it.
+    def _on_unicode(self, value, merge_with):
+        return self._on_str(value, merge_with)
+
+    # On encountering a string object to merge with we will
+    # perform the following action, if appending we will
+    # merge them together, otherwise we will just return value.
+    def _on_str(self, value, merge_with):
+        if not isinstance(value, (basestring)):
+            return merge_with
+        if not self._append:
+            return merge_with
+        if isinstance(value, unicode):
+            return value + unicode(merge_with)
+        else:
+            return value + str(merge_with)