Attempt 2 Make class variables immutable

CHANGES.rst

@@ -3,6 +3,7 @@
 
 - Drop support for Python 3.8 in accordance with NEP 29. [#180]
 - Update ``RepresentationConverter`` for new class paths in astropy [#181]
+- Update Converters so that all Class Variables are immutable [#188]
 
 0.4.0 (2023-03-20)
 ------------------

asdf_astropy/converters/coordinates/angle.py

@@ -2,9 +2,8 @@
 
 
 class AngleConverter(QuantityConverter):
-    tags = ["tag:astropy.org:astropy/coordinates/angle-*"]
-
-    types = ["astropy.coordinates.angles.Angle"]
+    tags = ("tag:astropy.org:astropy/coordinates/angle-*",)
+    types = ("astropy.coordinates.angles.Angle",)
 
     def from_yaml_tree(self, node, tag, ctx):
         from astropy.coordinates.angles import Angle
@@ -13,9 +12,8 @@ def from_yaml_tree(self, node, tag, ctx):
 
 
 class LatitudeConverter(QuantityConverter):
-    tags = ["tag:astropy.org:astropy/coordinates/latitude-*"]
-
-    types = ["astropy.coordinates.angles.Latitude"]
+    tags = ("tag:astropy.org:astropy/coordinates/latitude-*",)
+    types = ("astropy.coordinates.angles.Latitude",)
 
     def from_yaml_tree(self, node, tag, ctx):
         from astropy.coordinates.angles import Latitude
@@ -24,9 +22,8 @@ def from_yaml_tree(self, node, tag, ctx):
 
 
 class LongitudeConverter(QuantityConverter):
-    tags = ["tag:astropy.org:astropy/coordinates/longitude-*"]
-
-    types = ["astropy.coordinates.angles.Longitude"]
+    tags = ("tag:astropy.org:astropy/coordinates/longitude-*",)
+    types = ("astropy.coordinates.angles.Longitude",)
 
     def to_yaml_tree(self, obj, tag, ctx):
         tree = super().to_yaml_tree(obj, tag, ctx)

asdf_astropy/converters/coordinates/earth_location.py

@@ -2,9 +2,8 @@
 
 
 class EarthLocationConverter(Converter):
-    tags = ["tag:astropy.org:astropy/coordinates/earthlocation-*"]
-
-    types = ["astropy.coordinates.earth.EarthLocation"]
+    tags = ("tag:astropy.org:astropy/coordinates/earthlocation-*",)
+    types = ("astropy.coordinates.earth.EarthLocation",)
 
     def to_yaml_tree(self, obj, tag, ctx):
         return obj.info._represent_as_dict()

asdf_astropy/converters/coordinates/frame.py

@@ -54,11 +54,10 @@ def from_yaml_tree(self, node, tag, ctx):
 
 
 class LegacyICRSConverter(Converter):
-    tags = ["tag:astropy.org:astropy/coordinates/frames/icrs-1.0.0"]
-
+    tags = ("tag:astropy.org:astropy/coordinates/frames/icrs-1.0.0",)
     # Leave the types list empty so that the 1.1.0 ICRS converter
     # is used on write.
-    types = []
+    types = ()
 
     def to_yaml_tree(self, obj, tag, ctx):
         from astropy.units import Quantity

asdf_astropy/converters/coordinates/representation.py

@@ -2,9 +2,8 @@
 
 
 class RepresentationConverter(Converter):
-    tags = ["tag:astropy.org:astropy/coordinates/representation-*"]
-
-    types = [
+    tags = ("tag:astropy.org:astropy/coordinates/representation-*",)
+    types = (
         "astropy.coordinates.representation.CartesianDifferential",
         "astropy.coordinates.representation.CartesianRepresentation",
         "astropy.coordinates.representation.CylindricalDifferential",
@@ -34,7 +33,7 @@ class RepresentationConverter(Converter):
         "astropy.coordinates.representation.spherical.UnitSphericalRepresentation",
         "astropy.coordinates.representation.spherical.UnitSphericalDifferential",
         "astropy.coordinates.representation.spherical.UnitSphericalCosLatDifferential",
-    ]
+    )
 
     def to_yaml_tree(self, obj, tag, ctx):
         components = {}

asdf_astropy/converters/coordinates/sky_coord.py

@@ -2,9 +2,8 @@
 
 
 class SkyCoordConverter(Converter):
-    tags = ["tag:astropy.org:astropy/coordinates/skycoord-*"]
-
-    types = ["astropy.coordinates.sky_coordinate.SkyCoord"]
+    tags = ("tag:astropy.org:astropy/coordinates/skycoord-*",)
+    types = ("astropy.coordinates.sky_coordinate.SkyCoord",)
 
     def to_yaml_tree(self, obj, tag, ctx):
         return obj.info._represent_as_dict()

asdf_astropy/converters/coordinates/spectral_coord.py

@@ -3,9 +3,8 @@
 
 
 class SpectralCoordConverter(Converter):
-    tags = ["tag:astropy.org:astropy/coordinates/spectralcoord-*"]
-
-    types = ["astropy.coordinates.spectral_coordinate.SpectralCoord"]
+    tags = ("tag:astropy.org:astropy/coordinates/spectralcoord-*",)
+    types = ("astropy.coordinates.spectral_coordinate.SpectralCoord",)
 
     def to_yaml_tree(self, obj, tag, ctx):
         node = {

asdf_astropy/converters/fits/fits.py

@@ -66,10 +66,10 @@ def from_yaml_tree(self, node, tag, ctx):
 
 
 class AsdfFitsConverter(FitsConverter):
-    tags = ["tag:stsci.edu:asdf/fits/fits-*"]
-    types = []
+    tags = ("tag:stsci.edu:asdf/fits/fits-*",)
+    types = ()
 
 
 class AstropyFitsConverter(FitsConverter):
-    tags = ["tag:astropy.org:astropy/fits/fits-*"]
-    types = ["astropy.io.fits.hdu.hdulist.HDUList"]
+    tags = ("tag:astropy.org:astropy/fits/fits-*",)
+    types = ("astropy.io.fits.hdu.hdulist.HDUList",)

asdf_astropy/converters/table/table.py

@@ -3,12 +3,11 @@
 
 
 class ColumnConverter(Converter):
-    tags = ["tag:stsci.edu:asdf/core/column-*"]
-
-    types = [
+    tags = ("tag:stsci.edu:asdf/core/column-*",)
+    types = (
         "astropy.table.column.Column",
         "astropy.table.column.MaskedColumn",
-    ]
+    )
 
     def to_yaml_tree(self, obj, tag, ctx):
         node = {"data": obj.data, "name": obj.name}
@@ -46,9 +45,8 @@ def from_yaml_tree(self, node, tag, ctx):
 
 
 class AsdfTableConverter(Converter):
-    tags = ["tag:stsci.edu:asdf/core/table-*"]
-
-    types = []
+    tags = ("tag:stsci.edu:asdf/core/table-*",)
+    types = ()
 
     def to_yaml_tree(self, obj, tag, ctx):
         msg = "astropy does not support writing astropy.table.Table with the ASDF table-1.0.0 tag"
@@ -61,12 +59,11 @@ def from_yaml_tree(self, node, tag, ctx):
 
 
 class AstropyTableConverter(Converter):
-    tags = ["tag:astropy.org:astropy/table/table-*"]
-
-    types = [
+    tags = ("tag:astropy.org:astropy/table/table-*",)
+    types = (
         "astropy.table.table.Table",
         "astropy.table.table.QTable",
-    ]
+    )
 
     def to_yaml_tree(self, obj, tag, ctx):
         from astropy.table import QTable

asdf_astropy/converters/time/time.py

@@ -12,9 +12,8 @@
 
 
 class TimeConverter(Converter):
-    tags = ["tag:stsci.edu:asdf/time/time-*"]
-
-    types = ["astropy.time.core.Time"]
+    tags = ("tag:stsci.edu:asdf/time/time-*",)
+    types = ("astropy.time.core.Time",)
 
     def to_yaml_tree(self, obj, tag, ctx):
         from astropy.time import Time

asdf_astropy/converters/time/time_delta.py

@@ -2,9 +2,8 @@
 
 
 class TimeDeltaConverter(Converter):
-    tags = ["tag:astropy.org:astropy/time/timedelta-*"]
-
-    types = ["astropy.time.core.TimeDelta"]
+    tags = ("tag:astropy.org:astropy/time/timedelta-*",)
+    types = ("astropy.time.core.TimeDelta",)
 
     def to_yaml_tree(self, obj, tag, ctx):
         return obj.info._represent_as_dict()

asdf_astropy/converters/transform/compound.py

@@ -34,7 +34,7 @@ class CompoundConverter(TransformConverterBase):
     ASDF serialization support for CompoundModel.
     """
 
-    tags = [
+    tags = (
         "tag:stsci.edu:asdf/transform/add-*",
         "tag:stsci.edu:asdf/transform/subtract-*",
         "tag:stsci.edu:asdf/transform/multiply-*",
@@ -43,9 +43,8 @@ class CompoundConverter(TransformConverterBase):
         "tag:stsci.edu:asdf/transform/compose-*",
         "tag:stsci.edu:asdf/transform/concatenate-*",
         "tag:stsci.edu:asdf/transform/fix_inputs-*",
-    ]
-
-    types = ["astropy.modeling.core.CompoundModel"]
+    )
+    types = ("astropy.modeling.core.CompoundModel",)
 
     def select_tag(self, model, tags, ctx):
         tag_name = _OPERATOR_TO_TAG_NAME[model.op]

asdf_astropy/converters/transform/functional_models.py

@@ -14,12 +14,11 @@ class ConstantConverter(TransformConverterBase):
     # previously all values were 1D.
     _2D_MIN_VERSION = parse_version("1.4.0")
 
-    tags = ["tag:stsci.edu:asdf/transform/constant-*"]
-
-    types = [
+    tags = ("tag:stsci.edu:asdf/transform/constant-*",)
+    types = (
         "astropy.modeling.functional_models.Const1D",
         "astropy.modeling.functional_models.Const2D",
-    ]
+    )
 
     def to_yaml_tree_transform(self, model, tag, ctx):
         from astropy.modeling.functional_models import Const1D, Const2D

asdf_astropy/converters/transform/mappings.py

@@ -8,9 +8,8 @@ class IdentityConverter(TransformConverterBase):
     ASDF support for serializing the Identity model.
     """
 
-    tags = ["tag:stsci.edu:asdf/transform/identity-*"]
-
-    types = ["astropy.modeling.mappings.Identity"]
+    tags = ("tag:stsci.edu:asdf/transform/identity-*",)
+    types = ("astropy.modeling.mappings.Identity",)
 
     def to_yaml_tree_transform(self, model, tag, ctx):
         node = {}
@@ -29,9 +28,8 @@ class RemapAxesConverter(TransformConverterBase):
     ASDF support for serializing the Mapping model
     """
 
-    tags = ["tag:stsci.edu:asdf/transform/remap_axes-*"]
-
-    types = ["astropy.modeling.mappings.Mapping"]
+    tags = ("tag:stsci.edu:asdf/transform/remap_axes-*",)
+    types = ("astropy.modeling.mappings.Mapping",)
 
     def to_yaml_tree_transform(self, model, tag, ctx):
         node = {"mapping": list(model.mapping)}
@@ -53,9 +51,8 @@ class UnitsMappingConverter(Converter):
     from other models.
     """
 
-    tags = ["tag:astropy.org:astropy/transform/units_mapping-*"]
-
-    types = ["astropy.modeling.mappings.UnitsMapping"]
+    tags = ("tag:astropy.org:astropy/transform/units_mapping-*",)
+    types = ("astropy.modeling.mappings.UnitsMapping",)
 
     def to_yaml_tree(self, model, tag, ctx):
         node = {}

asdf_astropy/converters/transform/math_functions.py

@@ -55,9 +55,8 @@ class MathFunctionsConverter(TransformConverterBase):
     each of which corresponds to a numpy ufunc.
     """
 
-    tags = ["tag:stsci.edu:asdf/transform/math_functions-*"]
-
-    types = ["astropy.modeling.math_functions." + m for m in _MODEL_NAMES]
+    tags = ("tag:stsci.edu:asdf/transform/math_functions-*",)
+    types = tuple("astropy.modeling.math_functions." + m for m in _MODEL_NAMES)
 
     def to_yaml_tree_transform(self, model, tag, ctx):
         return {"func_name": model.func.__name__}

asdf_astropy/converters/transform/polynomial.py

@@ -16,12 +16,11 @@ class PolynomialConverter(TransformConverterBase):
     # versions because they don't validate.
     _DOMAIN_WINDOW_MIN_VERSION = parse_version("1.2.0")
 
-    tags = ["tag:stsci.edu:asdf/transform/polynomial-*"]
-
-    types = [
+    tags = ("tag:stsci.edu:asdf/transform/polynomial-*",)
+    types = (
         "astropy.modeling.polynomial.Polynomial1D",
         "astropy.modeling.polynomial.Polynomial2D",
-    ]
+    )
 
     def to_yaml_tree_transform(self, model, tag, ctx):
         from astropy.modeling.polynomial import Polynomial1D, Polynomial2D
@@ -95,37 +94,38 @@ def from_yaml_tree_transform(self, node, tag, ctx):
         return model
 
 
+_CLASS_NAME_TO_POLY_INFO = {
+    "Legendre1D": ("legendre", 1),
+    "Legendre2D": ("legendre", 2),
+    "Chebyshev1D": ("chebyshev", 1),
+    "Chebyshev2D": ("chebyshev", 2),
+    "Hermite1D": ("hermite", 1),
+    "Hermite2D": ("hermite", 2),
+}
+
+_POLY_INFO_TO_CLASS_NAME = {v: k for k, v in _CLASS_NAME_TO_POLY_INFO.items()}
+
+
 class OrthoPolynomialConverter(TransformConverterBase):
     """
     ASDF support for serializing models that inherit
     OrthoPolyomialBase.
     """
 
     # Map of model class name to (polynomial type, number of dimensions) tuple:
-    _CLASS_NAME_TO_POLY_INFO = {
-        "Legendre1D": ("legendre", 1),
-        "Legendre2D": ("legendre", 2),
-        "Chebyshev1D": ("chebyshev", 1),
-        "Chebyshev2D": ("chebyshev", 2),
-        "Hermite1D": ("hermite", 1),
-        "Hermite2D": ("hermite", 2),
-    }
-
-    _POLY_INFO_TO_CLASS_NAME = {v: k for k, v in _CLASS_NAME_TO_POLY_INFO.items()}
-
-    tags = ["tag:stsci.edu:asdf/transform/ortho_polynomial-*"]
 
-    types = [
+    tags = ("tag:stsci.edu:asdf/transform/ortho_polynomial-*",)
+    types = (
         "astropy.modeling.polynomial.Legendre1D",
         "astropy.modeling.polynomial.Legendre2D",
         "astropy.modeling.polynomial.Chebyshev1D",
         "astropy.modeling.polynomial.Chebyshev2D",
         "astropy.modeling.polynomial.Hermite1D",
         "astropy.modeling.polynomial.Hermite2D",
-    ]
+    )
 
     def to_yaml_tree_transform(self, model, tag, ctx):
-        poly_type = self._CLASS_NAME_TO_POLY_INFO[model.__class__.__name__][0]
+        poly_type = _CLASS_NAME_TO_POLY_INFO[model.__class__.__name__][0]
         if model.n_inputs == 1:
             coefficients = np.array(model.parameters)
         else:
@@ -157,7 +157,7 @@ def from_yaml_tree_transform(self, node, tag, ctx):
         poly_type = node["polynomial_type"]
         n_dim = coefficients.ndim
 
-        class_name = self._POLY_INFO_TO_CLASS_NAME[(poly_type, n_dim)]
+        class_name = _POLY_INFO_TO_CLASS_NAME[(poly_type, n_dim)]
         model_type = getattr(polynomial, class_name)
 
         coefficients = np.asarray(node["coefficients"])

asdf_astropy/converters/transform/properties.py

@@ -3,8 +3,8 @@
 
 
 class ModelBoundingBoxConverter(Converter):
-    tags = ["tag:stsci.edu:asdf/transform/property/bounding_box-1.0.0"]
-    types = ["astropy.modeling.bounding_box.ModelBoundingBox"]
+    tags = ("tag:stsci.edu:asdf/transform/property/bounding_box-1.0.0",)
+    types = ("astropy.modeling.bounding_box.ModelBoundingBox",)
 
     def to_yaml_tree(self, bbox, tag, ctx):
         return {
@@ -40,8 +40,8 @@ def create_bounding_box(model, cbbox=None):
 
 
 class CompoundBoundingBoxConverter(Converter):
-    tags = ["tag:stsci.edu:asdf/transform/property/compound_bounding_box-1.0.0"]
-    types = ["astropy.modeling.bounding_box.CompoundBoundingBox"]
+    tags = ("tag:stsci.edu:asdf/transform/property/compound_bounding_box-1.0.0",)
+    types = ("astropy.modeling.bounding_box.CompoundBoundingBox",)
 
     def to_yaml_tree(self, cbbox, tag, ctx):
         node = {