add jrnl interface test for overriden configurations

tests/test_config.py

@@ -0,0 +1,25 @@
+import pytest 
+import pytest_mock 
+import mock
+
+import yaml
+from jrnl.args import parse_args
+from jrnl.jrnl import run 
+from jrnl import install 
+
+@pytest.fixture()
+def minimal_config():
+    with open('features/data/configs/editor.yaml','r') as cfg_file:
+        yield yaml.load(cfg_file.read())
+
+from jrnl import jrnl
+@mock.patch.object(jrnl,'write_mode')
+@mock.patch.object(install,'load_or_install_jrnl')
+def test_override_configured_editor(mock_load_or_install, mock_write_mode, minimal_config): 
+    mock_load_or_install.return_value = minimal_config
+    cli_args = ['--override','{\"editor\": \"nano\"}' ]
+    parser = parse_args(cli_args)
+    assert parser.config_override.__len__() == 1
+    with mock.patch('subprocess.call'):
+        res = run(parser)
+    assert res==None