Add a unit test for connect_host.

Author: vivekverma-arista

test/test_redis_connect_host.py

@@ -0,0 +1,27 @@
+import os
+import sys
+
+if sys.version_info.major == 3:
+    from unittest import mock
+else:
+    import mock
+
+modules_path = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
+sys.path.insert(0, os.path.join(modules_path, 'src'))
+
+from swsssdk import SonicV2Connector
+
+def test_redis_connect_host():
+    mock_dbintf = mock.MagicMock()
+    db = SonicV2Connector()
+    db.dbintf = mock_dbintf
+    db.dbintf.redis_kwargs = {}
+
+    db_name = 'COUNTERS_DB'
+    host = '127.0.0.1'
+
+    db.connect_host(db_name, host)
+    mock_dbintf.connect.assert_called_once_with(2, db_name, True)
+
+    assert db.dbintf.redis_kwargs["host"] == host
+    assert db.dbintf.redis_kwargs["port"] == 6379