Fixed instance checker in voidMat (#264)

* Fixed instance checker in voidMat

Fixed the void mat instance checker to  check for the first entry being an int, second entry being a float or int, and the third entry being a str.

* Update config_cadtocsg_non_defaults.json

Updated config_cadtocsg_non_defaults.json to test voidMat with a material defined

* Update tests/config_cadtocsg_non_defaults.json

* Update src/geouned/GEOUNED/utils/data_classes.py

black format

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Co-authored-by: Patrick Sauvan <psauvan@ind.uned.es>

src/geouned/GEOUNED/utils/data_classes.py

@@ -769,10 +769,17 @@ def voidMat(self):
     def voidMat(self, voidMat: list):
         if not isinstance(voidMat, list):
             raise TypeError(f"geouned.Settings.voidMat should be a list, not a {type(voidMat)}")
-        for entry in voidMat:
-            if not isinstance(entry, int):
-                raise TypeError(f"geouned.Settings.voidMat should be a list of ints, not a {type(entry)}")
-        self._voidMat = voidMat
+        if len(voidMat) == 0:
+            self._voidMat = voidMat
+        else:
+            if not isinstance(voidMat[0], int):
+                raise TypeError(f"first entry of geouned.Settings.voidMat should be an int, not a {type(entry)}")
+            if not isinstance(voidMat[1], int):
+                if not isinstance(voidMat[1], float):
+                    raise TypeError(f"second entry of geouned.Settings.voidMat should be an int or float, not a {type(entry)}")
+            if not isinstance(voidMat[2], str):
+                raise TypeError(f"third entry of geouned.Settings.voidMat should be a str, not a {type(entry)}")
+            self._voidMat = voidMat
 
     @property
     def voidExclude(self):

tests/config_cadtocsg_non_defaults.json

@@ -12,6 +12,7 @@
         "P_abc": "15.7e"
     },
     "Settings": {
-        "matFile": "non default"
+        "matFile": "non default",
+        "voidMat": [1, -1.29E-3, "Dry air"]
     }
-}
+}