check for bad read_* and write_* methods

raise a ProgrammingError when a read_<param> or write_<param>
method is defined, but <param> is no parameter.

Change-Id: Iae4e617d078229182a90b202a6f81ebc49050118
Reviewed-on: https://forge.frm2.tum.de/review/c/sine2020/secop/playground/+/27386
Tested-by: Jenkins Automated Tests <pedersen+jenkins@frm2.tum.de>
Reviewed-by: Enrico Faulhaber <enrico.faulhaber@frm2.tum.de>
Reviewed-by: Markus Zolliker <markus.zolliker@psi.ch>

secop/modules.py

@@ -176,11 +176,17 @@ class HasAccessibles(HasProperties):
                     setattr(cls, 'write_' + pname, wrapped_wfunc)
                     wrapped_wfunc.__wrapped__ = True
 
-        # check information about Command's
+        # check for programming errors
         for attrname in cls.__dict__:
-            if attrname.startswith('do_'):
+            prefix, _, pname = attrname.partition('_')
+            if not pname:
+                continue
+            if prefix == 'do':
                 raise ProgrammingError('%r: old style command %r not supported anymore'
                                        % (cls.__name__, attrname))
+            if prefix in ('read', 'write') and not isinstance(accessibles.get(pname), Parameter):
+                raise ProgrammingError('%s.%s defined, but %r is no parameter'
+                                       % (cls.__name__, attrname, pname))
 
         res = {}
         # collect info about properties

test/test_modules.py

@@ -458,3 +458,23 @@ def test_command_none():
 
     assert 'stop' in Mod('o', logger, {'description': ''}, srv).accessibles
     assert 'stop' not in Mod2('o', logger, {'description': ''}, srv).accessibles
+
+
+def test_bad_method():
+    class Mod0(Drivable):  # pylint: disable=unused-variable
+        def write_target(self, value):
+            pass
+
+    with pytest.raises(ProgrammingError):
+        class Mod1(Drivable):  # pylint: disable=unused-variable
+            def write_taget(self, value):
+                pass
+
+    class Mod2(Drivable):  # pylint: disable=unused-variable
+        def read_value(self, value):
+            pass
+
+    with pytest.raises(ProgrammingError):
+        class Mod3(Drivable):  # pylint: disable=unused-variable
+            def read_valu(self, value):
+                pass