Refs #4586. Fix if None is passed as filename

Code/Mantid/scripts/Inelastic/DirectEnergyConversion.py

@@ -112,8 +112,11 @@ def diagnose(self, white, **kwargs):
         whiteintegrals = self.do_white(white, None, None) # No grouping yet
         if 'second_white' in kwargs:
             second_white = kwargs['second_white']
-            other_whiteintegrals = self.do_white(second_white, None, None) # No grouping yet
-            kwargs['second_white'] = other_whiteintegrals
+            if second_white is None:
+                del kwargs['second_white']
+            else:
+                other_whiteintegrals = self.do_white(second_white, None, None) # No grouping yet
+                kwargs['second_white'] = other_whiteintegrals
 
         # Get the background/total counts from the sample if present
         if 'sample' in kwargs:

Code/Mantid/scripts/Inelastic/diagnostics.py

@@ -71,17 +71,15 @@ def diagnose(white_int, **kwargs):
     # Each element is the mask workspace name then the number of failures
     test_results = [ [None, None], [None, None], [None, None], [None, None], [None, None]]
 
-    # Load the hard mask file if necessary
-    hard_mask_spectra = ''
-    if 'hard_mask' in kwargs:
+    # Hard mask
+    hardmask_file = kwargs.get('hard_mask', None)
+    if hardmask_file is not None:
         hard_mask_spectra = common.load_mask(parser.hard_mask)
         test_results[0][0] = os.path.basename(parser.hard_mask)
-
-    # Hard mask
-    masking = MaskDetectors(white_int, SpectraList=hard_mask_spectra)
-    # Find out how many detectors we hard masked
-    hard_mask_spectra = masking['SpectraList'].value
-    test_results[0][1] = len(hard_mask_spectra)
+        masking = MaskDetectors(white_int, SpectraList=hard_mask_spectra)
+        # Find out how many detectors we hard masked
+        hard_mask_spectra = masking['SpectraList'].value
+        test_results[0][1] = len(hard_mask_spectra)
 
     # White beam Test
     __white_masks, num_failed = do_white_test(white_int, parser.tiny, parser.huge,