add copy and json lazy_nodes tests

asdf/_lazy_nodes.py

@@ -71,7 +71,8 @@ class AsdfListNode(AsdfNode, collections.UserList, list):
     def __init__(self, data=None, af_ref=None):
         if data is None:
             data = []
-        super().__init__(data, af_ref)
+        AsdfNode.__init__(self, data, af_ref)
+        collections.UserList.__init__(self, data)
         list.__init__(self, data)
 
     def __eq__(self, other):
@@ -136,7 +137,8 @@ class AsdfDictNode(AsdfNode, collections.UserDict, dict):
     def __init__(self, data=None, af_ref=None):
         if data is None:
             data = {}
-        super().__init__(data, af_ref)
+        AsdfNode.__init__(self, data, af_ref)
+        collections.UserDict.__init__(self, data)
         dict.__init__(self, data)
 
     def __eq__(self, other):
@@ -192,4 +194,8 @@ def __getitem__(self, key):
 
 
 class AsdfOrderedDictNode(AsdfDictNode, collections.OrderedDict):
-    pass
+    def __init__(self, data=None, af_ref=None):
+        if data is None:
+            data = collections.OrderedDict()
+        AsdfDictNode.__init__(self, data, af_ref)
+        collections.OrderedDict.__init__(self, data)

asdf/_tests/test_lazy_nodes.py

@@ -1,4 +1,6 @@
 import collections
+import copy
+import json
 import weakref
 
 import numpy as np
@@ -94,6 +96,34 @@ def test_ordered_dict():
     assert isinstance(node["a"]["b"][2], _lazy_nodes.AsdfOrderedDictNode)
 
 
+@pytest.mark.parametrize(
+    "node",
+    [
+        _lazy_nodes.AsdfDictNode({"a": 1, "b": 2}),
+        _lazy_nodes.AsdfListNode([1, 2, 3]),
+        _lazy_nodes.AsdfOrderedDictNode({"a": 1, "b": 2}),
+    ],
+)
+@pytest.mark.parametrize("copy_operation", [copy.copy, copy.deepcopy])
+def test_copy(node, copy_operation):
+    copied_node = copy_operation(node)
+    assert isinstance(copied_node, type(node))
+    assert copied_node == node
+
+
+@pytest.mark.parametrize(
+    "node",
+    [
+        _lazy_nodes.AsdfDictNode({"a": 1, "b": 2}),
+        _lazy_nodes.AsdfListNode([1, 2, 3]),
+        _lazy_nodes.AsdfOrderedDictNode({"a": 1, "b": 2}),
+    ],
+)
+def test_json_serialization(node):
+    rt_node = json.loads(json.dumps(node))
+    assert rt_node == node
+
+
 def test_cache_clear_on_close(tmp_path):
     fn = tmp_path / "test.asdf"