Merge branch 'master' into dd/hotfix

desc/compute/_curve.py

@@ -1061,9 +1061,7 @@ def _torsion(params, transforms, profiles, data, **kwargs):
     coordinates="",
     data=["ds", "x_s"],
     parameterization=[
-        "desc.geometry.curve.FourierRZCurve",
-        "desc.geometry.curve.FourierXYZCurve",
-        "desc.geometry.curve.FourierPlanarCurve",
+        "desc.geometry.core.Curve",
     ],
 )
 def _length(params, transforms, profiles, data, **kwargs):

desc/compute/data_index.py

@@ -148,10 +148,20 @@ def _decorator(func):
             flag = False
             for base_class, superclasses in _class_inheritance.items():
                 if p in superclasses or p == base_class:
+                    # already registered ?
                     if name in data_index[base_class]:
-                        raise ValueError(
-                            f"Already registered function with parameterization {p} and name {name}."
-                        )
+                        if p == data_index[base_class][name]["parameterization"]:
+                            raise ValueError(
+                                f"Already registered function with parameterization {p} and name {name}."
+                            )
+                        # if it was already registered from a parent class, we prefer
+                        # the child class.
+                        inheritance_order = [base_class] + superclasses
+                        if inheritance_order.index(p) > inheritance_order.index(
+                            data_index[base_class][name]["parameterization"]
+                        ):
+                            continue
+                    d["parameterization"] = p
                     data_index[base_class][name] = d.copy()
                     all_kwargs[base_class][name] = kwargs
                     for alias in aliases:
@@ -228,7 +238,6 @@ def _decorator(func):
     ],
     "desc.magnetic_fields._core.OmnigenousField": [],
 }
-
 data_index = {p: {} for p in _class_inheritance.keys()}
 all_kwargs = {p: {} for p in _class_inheritance.keys()}
 allowed_kwargs = set()

docs/adding_compute_funs.rst

@@ -97,8 +97,14 @@ metadata about the quantity. The necessary fields are detailed below:
   are specified in ``axis_limit_data``. The dependencies specified in this list are
   marked to be computed only when there is a node at the magnetic axis.
 * ``parameterization``: what sorts of DESC objects is this function for. Most functions
-  will just be for ``Equilibrium``, but some methods may also be for ``desc.geometry.Curve``,
-  or specific types eg ``desc.geometry.FourierRZCurve``.
+  will just be for ``Equilibrium``, but some methods may also be for ``desc.geometry.core.Curve``,
+  or specific types eg ``desc.geometry.curve.FourierRZCurve``. If a quantity is computed differently
+  for a subclass versus a superclass, then one may define a compute function for the superclass
+  (e.g. for ``desc.geometry.Curve``) which will be used for that class and any of its subclasses,
+  and then if a specific subclass requires a different method, one may define a second compute function for
+  the same quantity, with a parameterization for that subclass (e.g. ``desc.geometry.curve.SplineXYZCurve``).
+  See the compute definitions for the ``length`` quantity in ``compute/_curve.py`` for an example of this,
+  which is similar to the inheritance structure of Python classes.
 * ``kwargs``: If the compute function requires any additional arguments they should
   be specified like ``kwarg="description"`` where ``kwarg`` is replaced by the actual
   keyword argument, and ``"description"`` is a string describing what it is.