add unit test for masked array roundtripping

asdf/_tests/test_masked.py

@@ -0,0 +1,26 @@
+import numpy.ma
+import pytest
+
+import asdf
+from asdf._tests._helpers import assert_tree_match
+
+
+@pytest.mark.parametrize(
+    "mask",
+    [
+        [[False, False, True], [False, True, False], [False, False, False]],
+        True,
+        False,
+    ],
+)
+def test_masked(mask, tmp_path):
+    tree = {
+        "a": 1,
+        "b": numpy.ma.array([[1, 0, 0], [0, 1, 0], [0, 0, 0]], mask=mask),
+    }
+    af = asdf.AsdfFile(tree)
+    fn = tmp_path / "masked.asdf"
+    af.write_to(fn)
+
+    with asdf.open(fn) as af:
+        assert_tree_match(tree, af.tree)