Allow to execute some tests with a simulator or with a real amplifier

To execute the tests with the installed Hamlib use the same long arguments
as ampctl, eg:
 bindings/python/test_amp.py --model {MODEL_NUMBER} --amp-file /dev/ttyUSB0 --serial-speed {BAUD}

To execute the tests from the build tree, add the path to the libraries
that you built, eg. from the root of the build tree:
 PYTHONPATH=bindings/:bindings/.libs/ ...your command...

bindings/python/conftest.py

@@ -5,6 +5,11 @@ import sys
 
 def pytest_addoption(parser):
     # using long options only because short options conflict with pytest's
+    if sys.argv[1].endswith("amp.py"):
+        parser.addoption('--model', type=int, default=1,
+                        metavar='ID', help='select amplifier model number')
+        parser.addoption('--amp-file', default=None,
+                        metavar='DEVICE', help='set device of the amplifier to operate on')
     if sys.argv[1].endswith("rig.py"):
         parser.addoption('--model', type=int, default=1,
                         metavar='ID', help='select radio model number')

bindings/python/test_amp.py

@@ -9,14 +9,12 @@ import Hamlib
 
 Hamlib.rig_set_debug(Hamlib.RIG_DEBUG_NONE)
 
-AMP_MODEL = Hamlib.AMP_MODEL_DUMMY
-
 class TestClass:
     """Container class for tests"""
 
-    def test_without_open(self):
+    def test_without_open(self, model):
         """Call all the methods that do not depend on open()"""
-        amp = Hamlib.Amp(AMP_MODEL)
+        amp = Hamlib.Amp(model)
         assert amp is not None
         assert amp.do_exception == 0
         assert amp.error_status == Hamlib.RIG_OK
@@ -38,9 +36,9 @@ class TestClass:
         assert amp.token_lookup("") is None
 
 
-    def test_with_open(self):
+    def test_with_open(self, model):
         """Call all the methods that depend on open()"""
-        amp = Hamlib.Amp(AMP_MODEL)
+        amp = Hamlib.Amp(model)
         assert amp is not None
 
         assert amp.state.comm_state == 0
@@ -70,9 +68,9 @@ class TestClass:
         assert info is None
 
 
-    def test_object_creation(self):
+    def test_object_creation(self, model):
         """Create all objects available"""
-        amp = Hamlib.Rig(AMP_MODEL)
+        amp = Hamlib.Rig(model)
         assert amp is not None
 
         assert isinstance(amp.caps, Hamlib.rig_caps)