Add type guard in FieldSet.__init__

Author: VeckoTheGecko

parcels/fieldset.py

@@ -42,7 +42,10 @@ class FieldSet:
     """
 
     def __init__(self, fields: list[Field | VectorField]):
-        # TODO Nick : Enforce fields to be list of Field or VectorField objects
+        for field in fields:
+            if not isinstance(field, (Field, VectorField)):
+                raise ValueError(f"Expected `field` to be a Field or VectorField object. Got {field}")
+
         self.fields = {f.name: f for f in fields}
         self.constants = {}
 

tests/v4/test_fieldset.py

@@ -21,6 +21,11 @@ def fieldset() -> FieldSet:
     )
 
 
+def test_fieldset_init_wrong_types():
+    with pytest.raises(ValueError, match="Expected `field` to be a Field or VectorField object. Got .*"):
+        FieldSet([1.0, 2.0, 3.0])
+
+
 def test_fieldset_add_constant(fieldset):
     fieldset.add_constant("test_constant", 1.0)
     assert fieldset.test_constant == 1.0