test for echo default behavior on getattr

attmap/attmap_echo.py

@@ -24,14 +24,12 @@ def __getattr__(self, item, default=None):
             return super(self.__class__, self).__getattr__(item, default)
         except (AttributeError, TypeError):
             # If not, triage and cope accordingly.
-            if item.startswith("_OrderedDict") or (item.startswith("__") and item.endswith("__")):
-                # Accommodate security-through-obscurity approach used by some libraries.
+            if item.startswith("_OrderedDict") or \
+                    (item.startswith("__") and item.endswith("__")):
+                # Accommodate security-through-obscurity approach of some libs.
                 error_reason = "Protected-looking attribute: {}".format(item)
                 raise AttributeError(error_reason)
-            if default is not None:
-                # For compatibility with ordinary getattr() call, allow default value.
-                return default
-            return item
+            return default if default is not None else item
 
     @property
     def _lower_type_bound(self):

tests/test_echo.py

@@ -32,3 +32,14 @@ def test_echo_is_type_dependent_and_access_dependent(
     assert key not in m
     with ExpectContext(expected, getter) as ctx:
         ctx(m, key)
+
+
+@pytest.mark.parametrize(
+    ["data", "name", "defval"],
+    [({}, "b", "arbval"), ({"a": 1}, "c", "random")])
+def test_echo_respects_default(data, name, defval):
+    assert name != defval    # Pretest so that assertions actually have meaning.
+    m = AttMapEcho(data)
+    assert name == getattr(m, name)
+    assert name == getattr(m, name, defval)
+    assert defval == m.__getattr__(name, defval)