added UsageError

ramannoodle/exceptions.py

@@ -40,6 +40,18 @@ def __init__(self, reason: str):
         pass
 
 
+class UsageError(Exception):
+    """Raised when a user does something they shouldn't.
+
+    This exception is used sparingly, as (ideally) the structure of the API should
+    dictate what the user should and shouldn't do.
+
+    """
+
+    def __init__(self, reason: str):
+        pass
+
+
 def _shape_string(shape: Sequence[int | None]) -> str:
     """Get a string representing a shape.
 

ramannoodle/polarizability/art.py

@@ -15,6 +15,7 @@
     get_shape_error,
     verify_ndarray_shape,
     InvalidDOFException,
+    UsageError,
 )
 
 
@@ -77,9 +78,13 @@ def add_dof(  # pylint: disable=too-many-arguments
     ) -> None:
         """Disable add_dof.
 
+        Raises
+        ------
+        UsageError
+
         :meta private:
         """
-        raise AttributeError("'ARTModel' object has no attribute 'add_dof'")
+        raise UsageError("add_dof should not be used; use add_art instead")
 
     def add_dof_from_files(
         self,
@@ -89,9 +94,15 @@ def add_dof_from_files(
     ) -> None:
         """Disable add_dof_from_files.
 
+        Raises
+        ------
+        UsageError
+
         :meta private:
         """
-        raise AttributeError("'ARTModel' object has no attribute 'add_dof_from_files'")
+        raise UsageError(
+            "add_dof_from_files should not be used; use add_art_from_files instead"
+        )
 
     def add_art(
         self,