postgresql: connect using keyword arguments in preference to a dsn

As well as being cleaner, this resolves a bug I've seen in the test suite,
where connections are incorrectly made to the default postgres database.

2 files changed, 8 insertions, 9 deletions

diff --git a/yoyo/backends.py b/yoyo/backends.py
index 6af931d..e1a32ee 100644
--- a/yoyo/backends.py
+++ b/yoyo/backends.py
@@ -446,17 +446,16 @@ class PostgresqlBackend(DatabaseBackend):
     driver_module = 'psycopg2'
 
     def connect(self, dburi):
-        connargs = []
+        connect_args = {'dbname': dburi.database}
         if dburi.username is not None:
-            connargs.append('user=%s' % dburi.username)
+            connect_args['user'] = dburi.username
         if dburi.password is not None:
-            connargs.append('password=%s' % dburi.password)
+            connect_args['password'] = dburi.password
         if dburi.port is not None:
-            connargs.append('port=%d' % dburi.port)
+            connect_args['port'] = dburi.port
         if dburi.hostname is not None:
-            connargs.append('host=%s' % dburi.hostname)
-        connargs.append('dbname=%s' % dburi.database)
-        return self.driver.connect(' '.join(connargs))
+            connect_args['host'] = dburi.hostname
+        return self.driver.connect(**connect_args)
 
     @contextmanager
     def disable_transactions(self):
diff --git a/yoyo/tests/test_connections.py b/yoyo/tests/test_connections.py
index f3b7440..9e5808c 100644
--- a/yoyo/tests/test_connections.py
+++ b/yoyo/tests/test_connections.py
@@ -77,8 +77,8 @@ def test_connections(import_module):
               db='northwind', foo='bar')),
         (backends.SQLiteBackend, 'sqlite3', call('northwind')),
         (backends.PostgresqlBackend, 'psycopg2',
-         call('user=scott password=tiger port=42 '
-              'host=db.example.org dbname=northwind')),
+         call(user='scott', password='tiger', port=42,
+              host='db.example.org', dbname='northwind')),
 
     ]