Explicitly check python types for setting properties

Previously we were allowing the type checking to be done implicitly
which would mark int as bool etc.

Framework/PythonInterface/mantid/api/src/Exports/Algorithm.cpp

@@ -97,15 +97,6 @@ template <typename T> void extractKwargs(const dict &kwargs, const std::string &
   }
 }
 
-template <typename T> boost::optional<T> extractObject(const object &obj) {
-  boost::python::extract<T> extractor(obj);
-
-  if (extractor.check())
-    return boost::optional<T>(extractor);
-  else
-    return boost::none;
-}
-
 // Signature createChildWithProps(self, name, startProgress, endProgress, enableLogging, version, **kwargs)
 object createChildWithProps(tuple args, dict kwargs) {
   std::shared_ptr<Algorithm> parentAlg = extract<std::shared_ptr<Algorithm>>(args[0]);
@@ -141,16 +132,21 @@ object createChildWithProps(tuple args, dict kwargs) {
     if (!curArg)
       continue;
 
-    if (auto val = extractObject<bool>(curArg))
+    const PyObject *rawptr = curArg.ptr();
+
+    // This currently  doesn't handle lists, but this could be retrofitted in future work
+    if (PyBool_Check(rawptr) == 1) {
+      bool val = extract<bool>(curArg);
       childAlg->setProperty(propName, val);
-    if (auto val = extractObject<float>(curArg))
+    } else if (PyFloat_Check(rawptr) == 1) {
+      double val = extract<double>(curArg);
       childAlg->setProperty(propName, val);
-    if (auto val = extractObject<int>(curArg))
+    } else if (PyLong_Check(rawptr) == 1) {
+      int val = extract<int>(curArg);
       childAlg->setProperty(propName, val);
-
-    // This currently  doesn't handle lists, but this could be retrofitted in future work
-    std::string propValue = extract<std::string>(curArg);
-    childAlg->setPropertyValue(propName, propValue);
+    } else {
+      childAlg->setPropertyValue(propName, extract<std::string>(curArg));
+    }
   }
   return object(childAlg);
 }

Framework/PythonInterface/test/python/mantid/api/AlgorithmTest.py

@@ -203,15 +203,28 @@ class AlgorithmTest(unittest.TestCase):
 
         self.assertIsNotNone(ws)
 
-    def xtest_createChildAlgorithm_with_int_arg(self):
+    def test_createChildAlgorithm_with_int_arg(self):
         parent_alg = AlgorithmManager.createUnmanaged('Load')
+        num_banks = 4
         child_alg = parent_alg.createChildAlgorithm("CreateSampleWorkspace", 0.0, 1.0, version=1,
-                                                    enableLogging=False, NumEvents=1000)
+                                                    enableLogging=False, NumBanks=num_banks)
+
         self.assertTrue(child_alg.isChild())
         child_alg.execute()
         ws = child_alg.getProperty("OutputWorkspace").value
 
-        self.assertIsNotNone(ws)
+        default_num_histos = 100  # From createSampleWorkspace
+        self.assertEquals((default_num_histos * num_banks), ws.getNumberHistograms())
+
+    def test_createChildAlgorithm_with_float_arg(self):
+        parent_alg = AlgorithmManager.createUnmanaged('Load')
+        child_alg = parent_alg.createChildAlgorithm("CreateSampleWorkspace", 0.0, 1.0, version=1,
+                                                    enableLogging=False, XMin=2.0)
+        self.assertTrue(child_alg.isChild())
+        child_alg.execute()
+        ws = child_alg.getProperty("OutputWorkspace").value
+
+        self.assertEquals(2.0, ws.readX(0)[0])
 
 
 if __name__ == '__main__':