add an explicit test that embedded and trailing nulls are stored properly

Author: ngoldbaum

stringdtype/tests/test_stringdtype.py

@@ -717,3 +717,10 @@ def test_datetime_cast(dtype):
         a = np.delete(a, 3)
 
     np.testing.assert_array_equal(sa, a.astype("U"))
+
+
+def test_null_roundtripping(dtype):
+    data = ["hello\0world", "ABC\0DEF\0\0"]
+    arr = np.array(data, dtype=dtype)
+    assert data[0] == arr[0]
+    assert data[1] == arr[1]