Add Ctrls integration tests

tests/test_integration_FG_Ctrls.py

@@ -0,0 +1,36 @@
+import pytest
+
+from flightgear_python.fg_if import CtrlsConnection
+
+
+pytestmark = pytest.mark.fg_integration
+ctrls_version = 27  # FlightGear-2020.3.19-x86_64.AppImage
+
+
+def test_ctrls_rx_and_tx_integration():
+    def rx_cb(ctrls_data, event_pipe):
+        (run_idx,) = event_pipe.child_recv()
+        child_callback_version = ctrls_data['version']
+        event_pipe.child_send(
+            (
+                run_idx,
+                child_callback_version,
+            )
+        )
+        return ctrls_data
+
+    ctrls_c = CtrlsConnection(ctrls_version)
+    ctrls_c.connect_rx('localhost', 5503, rx_cb)
+    ctrls_c.connect_tx('localhost', 5504)
+
+    for i in range(10):
+        ctrls_c.event_pipe.parent_send((i,))
+        # manually call the process instead of having the process spawn
+        ctrls_c._fg_packet_roundtrip()
+        run_idx, parent_callback_version = ctrls_c.event_pipe.parent_recv()
+        assert run_idx == i
+        assert parent_callback_version == ctrls_version
+
+    # Prevent 'ResourceWarning: unclosed' warning
+    ctrls_c.fg_rx_sock.close()
+    ctrls_c.fg_tx_sock.close()