Fix false warnings during layer ops (#174)

* fix 173

* update changelog

CHANGELOG.md

@@ -1,7 +1,13 @@
 # v3.0.5 - Changes staged
 
+## Features
+
 - Added functionality to `MitreAttackData` to retrieve a list of Procedure Examples by technique. [#172](https://github.com/mitre-attack/mitreattack-python/pull/172)
 
+## Fixes
+
+- Fixed a layer comparison issue causing false warnings to appear during layer operations. [#173](https://github.com/mitre-attack/mitreattack-python/issues/173).
+
 # v3.0.4 - 4/23/2024
 
 ## Features

mitreattack/navlayers/manipulators/layerops.py

@@ -181,9 +181,11 @@ def _merge_to_template(self, data, key=0):
         for entry in key_space:
             if entry != "techniques":
                 standard = _raw[entry]
-                if any(y != standard for y in [getattr(x.layer, entry) for x in collide]):
+                layer_entries = [getattr(x.layer, entry) for x in collide]
+                layer_entries = [y.get_dict() if hasattr(y, 'get_dict') else y for y in layer_entries]
+                if any(y != standard for y in layer_entries):
                     if entry == "domain":
-                        print("FATAL ERROR! Layer mis-match on domain. " "Exiting.")
+                        print("FATAL ERROR! Layer mis-match on domain. Exiting.")
                         raise MismatchedDomain
                     print(f"Warning! Layer mis-match detected for {entry}. Defaulting to {key}'s value")
                 out[entry] = standard