Update types for incomparable fix

CHANGELOG.md

@@ -1,5 +1,10 @@
 # Releases
 
+UNRELEASED
+
+* Fixed `T::Struct`'s of different classes returning `-1`; now returning `nil` as is expected of incomparable objects
+* Fixed incomparable attributes of different returning `-1` instead of `nil`
+
 1.0.0
 
 * Initial release: Extracted from [https://bellroy.com/](Bellroy) projects.

lib/t/struct/acts_as_comparable.rb

@@ -7,16 +7,19 @@ module ActsAsComparable
       extend T::Sig
       include ::Comparable
 
+      EQUAL = 0
       NOT_COMPARABLE = nil
 
-      sig { params(other: Object).returns(Integer) }
+      sig { params(other: Object).returns(T.nilable(Integer)) }
       def <=>(other)
         return NOT_COMPARABLE if other.class != T.unsafe(self).class
 
         T.unsafe(self).class.decorator.props.keys.each do |attribute_key|
           compare_result = T.unsafe(self).send(attribute_key) <=> other.send(attribute_key)
-          return T.cast(compare_result, Integer) if compare_result != EQUAL
+          return T.cast(compare_result, T.nilable(Integer)) if compare_result != EQUAL
         end
+
+        return EQUAL
       end
     end
   end