test for graceful closing of socket

test/test_printer_network.py

@@ -0,0 +1,23 @@
+#!/usr/bin/python
+
+import escpos.printer as printer
+import pytest
+import mock
+import socket
+
+
+@pytest.fixture
+def instance():
+    socket.socket.connect = mock.Mock()
+    return printer.Network("localhost")
+
+def test_close_without_open(instance):
+    """try to close without opening (should fail gracefully)
+
+    Currently we never open from our fixture, so calling close once
+    should be enough. In the future this might not be enough,
+    therefore we have to close twice in order to provoke an error
+    (if possible, this should not raise)
+    """
+    instance.close()
+    instance.close()