From b02904ee750a30f8e2246a326376b40358543101 Mon Sep 17 00:00:00 2001
From: Stefan Wojcik <wojcikstefan@gmail.com>
Date: Thu, 8 Dec 2016 15:18:17 -0500
Subject: [PATCH] BREAKING CHANGE rename ConnectionError to
 MongoEngineConnectionError to avoid conflicts with PY3's built-in
 ConnectionError

---
 mongoengine/connection.py           | 13 +++++++------
 tests/test_connection.py            | 15 ++++++++++-----
 tests/test_replicaset_connection.py |  4 ++--
 3 files changed, 19 insertions(+), 13 deletions(-)

diff --git a/mongoengine/connection.py b/mongoengine/connection.py
index 2db0d485..396ca61b 100644
--- a/mongoengine/connection.py
+++ b/mongoengine/connection.py
@@ -3,7 +3,7 @@ import six
 
 from mongoengine.python_support import IS_PYMONGO_3
 
-__all__ = ['ConnectionError', 'connect', 'register_connection',
+__all__ = ['MongoEngineConnectionError', 'connect', 'register_connection',
            'DEFAULT_CONNECTION_NAME']
 
 
@@ -16,7 +16,7 @@ else:
     READ_PREFERENCE = False
 
 
-class ConnectionError(Exception):
+class MongoEngineConnectionError(Exception):
     """Error raised when the database connection can't be established or
     when a connection with a requested alias can't be retrieved.
     """
@@ -139,12 +139,12 @@ def get_connection(alias=DEFAULT_CONNECTION_NAME, reconnect=False):
         return _connections[alias]
 
     # Validate that the requested alias exists in the _connection_settings.
-    # Raise ConnectionError if it doesn't.
+    # Raise MongoEngineConnectionError if it doesn't.
     if alias not in _connection_settings:
         msg = 'Connection with alias "%s" has not been defined' % alias
         if alias == DEFAULT_CONNECTION_NAME:
             msg = 'You have not defined a default connection'
-        raise ConnectionError(msg)
+        raise MongoEngineConnectionError(msg)
 
     def _clean_settings(settings_dict):
         irrelevant_fields = (
@@ -204,11 +204,12 @@ def get_connection(alias=DEFAULT_CONNECTION_NAME, reconnect=False):
         _connections[alias] = existing_connection
     else:
         # Otherwise, create the new connection for this alias. Raise
-        # ConnectionError if it can't be established.
+        # MongoEngineConnectionError if it can't be established.
         try:
             _connections[alias] = connection_class(**conn_settings)
         except Exception as e:
-            raise ConnectionError('Cannot connect to database %s :\n%s' % (alias, e))
+            raise MongoEngineConnectionError(
+                'Cannot connect to database %s :\n%s' % (alias, e))
 
     return _connections[alias]
 
diff --git a/tests/test_connection.py b/tests/test_connection.py
index fc032200..d8f1a79e 100644
--- a/tests/test_connection.py
+++ b/tests/test_connection.py
@@ -16,7 +16,8 @@ from mongoengine import (
 )
 from mongoengine.python_support import IS_PYMONGO_3
 import mongoengine.connection
-from mongoengine.connection import get_db, get_connection, ConnectionError
+from mongoengine.connection import (MongoEngineConnectionError, get_db,
+                                    get_connection)
 
 
 def get_tz_awareness(connection):
@@ -156,7 +157,10 @@ class ConnectionTest(unittest.TestCase):
         c.mongoenginetest.add_user("username", "password")
 
         if not IS_PYMONGO_3:
-            self.assertRaises(ConnectionError, connect, "testdb_uri_bad", host='mongodb://test:password@localhost')
+            self.assertRaises(
+                MongoEngineConnectionError, connect, 'testdb_uri_bad',
+                host='mongodb://test:password@localhost'
+            )
 
         connect("testdb_uri", host='mongodb://username:password@localhost/mongoenginetest')
 
@@ -226,10 +230,11 @@ class ConnectionTest(unittest.TestCase):
             self.assertRaises(OperationFailure, test_conn.server_info)
         else:
             self.assertRaises(
-                ConnectionError, connect, 'mongoenginetest', alias='test1',
+                MongoEngineConnectionError, connect, 'mongoenginetest',
+                alias='test1',
                 host='mongodb://username2:password@localhost/mongoenginetest'
             )
-            self.assertRaises(ConnectionError, get_db, 'test1')
+            self.assertRaises(MongoEngineConnectionError, get_db, 'test1')
 
         # Authentication succeeds with "authSource"
         connect(
@@ -250,7 +255,7 @@ class ConnectionTest(unittest.TestCase):
         """
         register_connection('testdb', 'mongoenginetest2')
 
-        self.assertRaises(ConnectionError, get_connection)
+        self.assertRaises(MongoEngineConnectionError, get_connection)
         conn = get_connection('testdb')
         self.assertTrue(isinstance(conn, pymongo.mongo_client.MongoClient))
 
diff --git a/tests/test_replicaset_connection.py b/tests/test_replicaset_connection.py
index 1eceebfd..a53f5903 100644
--- a/tests/test_replicaset_connection.py
+++ b/tests/test_replicaset_connection.py
@@ -15,7 +15,7 @@ else:
 
 import mongoengine
 from mongoengine import *
-from mongoengine.connection import ConnectionError
+from mongoengine.connection import MongoEngineConnectionError
 
 
 class ConnectionTest(unittest.TestCase):
@@ -38,7 +38,7 @@ class ConnectionTest(unittest.TestCase):
             conn = connect(db='mongoenginetest',
                            host="mongodb://localhost/mongoenginetest?replicaSet=rs",
                            read_preference=READ_PREF)
-        except ConnectionError as e:
+        except MongoEngineConnectionError as e:
             return
 
         if not isinstance(conn, CONN_CLASS):