Add a new test file for the SQLAlchemy transport

Add a simple test to parse URLs for SQLAlchemy.  This tests should prevent
issues that were introduced (GH-127 and the one fixed by f187ccdbcf)

kombu/tests/transport/test_sqlalchemy.py

@@ -0,0 +1,24 @@
+from __future__ import absolute_import
+
+import tempfile
+
+from kombu.connection import BrokerConnection
+from kombu.tests.utils import TestCase
+
+class test_sqlalchemy(TestCase):
+
+    def test_url_parser(self):
+        from kombu.transport import sqlalchemy
+
+        tmppath = tempfile.mkdtemp()
+
+        url = "sqlalchemy+sqlite://{path}/celerydb.sqlite".format(path=tmppath)
+        connection = BrokerConnection(url).connect()
+
+        url = "sqla+sqlite://{path}/celerydb.sqlite".format(path=tmppath)
+        connection = BrokerConnection(url).connect()
+
+        # Should prevent regression fixed by f187ccd
+        url = "sqlb+sqlite://{path}/celerydb.sqlite".format(path=tmppath)
+        with self.assertRaises(KeyError):
+            BrokerConnection(url).connect()