asdf validation error

asdf/tags/transform/__init__.py

@@ -8,5 +8,6 @@
 from .projections import *
 from .polynomial import *
 from .tabular import *
+from .test_fail import *
 
 

asdf/tags/transform/test_fail-1.1.0.yaml

@@ -0,0 +1,13 @@
+%YAML 1.1
+---
+$schema: "http://stsci.edu/schemas/yaml-schema/draft-01"
+id: "http://stsci.edu/schemas/jwst_pipeline/test_fail-1.1.0"
+tag: "tag:stsci.edu:jwst_pipeline/test_fail-1.1.0"
+title: >
+ Test NRSZCoords
+
+type: object
+properties:
+  model: 
+    $ref: ../asdf/transform/shift-1.1.0
+required: [model]

asdf/tags/transform/test_fail.py

@@ -0,0 +1,42 @@
+from __future__ import absolute_import, division, unicode_literals, print_function
+
+from ... import yamlutil
+from .basic import TransformType
+from astropy.modeling.core import Model
+
+__all__ = ['TestFailType', 'TestFail']
+
+
+class TestFail(Model):
+    """
+    Class to compute the z coordinate through the NIRSPEC grating wheel.
+
+    """
+    separable = False
+
+    inputs = ("x",)
+    outputs = ("z",)
+
+    def __init__(self, tab, **kwargs):
+        self.tab = tab
+        super(TestFail, self).__init__(**kwargs)
+
+    def evaluate(self, x):
+        return self.tab(x)
+
+
+class TestFailType(TransformType):
+    name = "transform/test_fail"
+    types = [TestFail]
+    version = "1.1.0"
+
+
+    @classmethod
+    def from_tree_transform(cls, node, ctx):
+        tab = node['model']
+        return TestFail(tab)
+
+    @classmethod
+    def to_tree_transform(cls, model, ctx):
+        node = {'model': model.tab}
+        return yamlutil.custom_tree_to_tagged_tree(node, ctx)