Merge pull request #38 from nim65s/devel

explicit error in case of misuse of dg.plug, fix #36

src/dynamic_graph/dynamic-graph-py.cc

@@ -40,10 +40,22 @@ PyObject* plug(PyObject* /*self*/, PyObject* args) {
 
   pObjIn = PyCapsule_GetPointer(objIn, "dynamic_graph.Signal");
   SignalBase<int>* signalIn = (SignalBase<int>*)pObjIn;
-  if (signalIn == NULL) return NULL;
+  if (signalIn == NULL) {
+      std::ostringstream oss;
+      oss << "dynamic_graph.plug(a, b): Argument 'b' must be of type 'dynamic_graph.Signal', but got "
+          << PyCapsule_GetName(objIn);
+      PyErr_SetString(PyExc_TypeError, oss.str().c_str());
+      return NULL;
+  }
   pObjOut = PyCapsule_GetPointer(objOut, "dynamic_graph.Signal");
   SignalBase<int>* signalOut = (SignalBase<int>*)pObjOut;
-  if (signalOut == NULL) return NULL;
+  if (signalOut == NULL) {
+      std::ostringstream oss;
+      oss << "dynamic_graph.plug(a, b): Argument 'a' must be of type 'dynamic_graph.Signal', but got "
+          << PyCapsule_GetName(objOut);
+      PyErr_SetString(PyExc_TypeError, oss.str().c_str());
+      return NULL;
+  }
   std::ostringstream os;
 
   try {
@@ -123,6 +135,14 @@ void initwrap(void)
     INITERROR;
   }
 
+  Py_XINCREF(st->dgpyError);
+  if (PyModule_AddObject(module, "dgpyError", st->dgpyError) < 0) {
+    Py_XDECREF(st->dgpyError);
+    Py_CLEAR(st->dgpyError);
+    Py_DECREF(module);
+    return NULL;
+  }
+
 #if PY_MAJOR_VERSION >= 3
   return module;
 #endif

unitTesting/interpreter-test-runfile.cc

@@ -62,7 +62,11 @@ int main(int argc, char** argv) {
   res = testFile("test_python-syntax_error.py",
                  std::string("  File \"test_python-syntax_error.py\", line 2\n"
                              "    hello world\n"
+#if PY_MINOR_VERSION >= 8
+                             "          ^\n"
+#else
                              "              ^\n"
+#endif
                              "SyntaxError: invalid syntax\n"),
                  numTest) &&
         res;

unitTesting/test_bindings.py

 import unittest
 
 import dynamic_graph as dg
+
 from custom_entity import CustomEntity
 
+ERR = "dynamic_graph.plug(a, b): Argument '%s' must be of type 'dynamic_graph.Signal', but got dynamic_graph.Entity"
+
 
 class BindingsTests(unittest.TestCase):
     def test_bindings(self):
@@ -15,10 +18,16 @@ class BindingsTests(unittest.TestCase):
         second = CustomEntity('second_entity')
         # Check that we can connect first.out to second.in
         dg.plug(first.signal('out_double'), second.signal('in_double'))
+
         # Check that we can't connect first.out to second
-        with self.assertRaises(ValueError) as cm:
+        with self.assertRaises(TypeError) as cm_in:
             dg.plug(first.signal('out_double'), second)
-        self.assertEqual(str(cm.exception), "PyCapsule_GetPointer called with incorrect name")
+        self.assertEqual(str(cm_in.exception), ERR % 'b')
+
+        # Check that we can't connect first to second.in
+        with self.assertRaises(TypeError) as cm_out:
+            dg.plug(first, second.signal('in_double'))
+        self.assertEqual(str(cm_out.exception), ERR % 'a')
 
 
 if __name__ == '__main__':