Fix values, value? and key returning a superclass' overridden value

CHANGELOG.md

@@ -1,5 +1,6 @@
 ### 1.2.1 (Next)
 
+* [#62](https://github.com/dblock/ruby-enum/issues/62): Fixed `values`, `value?` and `key` to not return a superclass' overridden value when a subclass redefines a key, matching the behavior of `to_h` and other methods - [@dblock](https://github.com/dblock).
 * Your contribution here.
 
 ### 1.2.0 (2026/8/14)

lib/ruby-enum/enum.rb

@@ -124,15 +124,9 @@ def keys
         _enum_hash.values.map(&:key)
       end
 
-      # Returns all enum values.
+      # Returns all enum values, including those defined in a superclass.
       def values
-        result = _own_enum_hash.values.map(&:value)
-
-        if superclass < Ruby::Enum
-          superclass.values + result
-        else
-          result
-        end
+        _enum_hash.values.map(&:value)
       end
 
       # Iterate over all enumerated values, including those defined in a superclass.
@@ -186,12 +180,16 @@ def _enum_hash
       # Returns the enums-by-value hash for this class merged with all of its
       # superclasses, with values defined in this class taking precedence over
       # those inherited from a superclass.
+      #
+      # Derived from _enum_hash (keyed by key) rather than merged directly by
+      # value, so that a superclass' stale value for a key overridden in this
+      # class doesn't linger, e.g. when a subclass redefines a key with a new
+      # value, the superclass' old value should no longer be found via value?
+      # or key.
       def _enums_by_value
-        @_enums_by_value ||= if superclass < Ruby::Enum
-                               superclass.send(:_enums_by_value).merge(_own_enums_by_value)
-                             else
-                               _own_enums_by_value
-                             end
+        @_enums_by_value ||= _enum_hash.each_with_object({}) do |(_key, enum), hash|
+          hash[enum.value] = enum
+        end
       end
 
       def upper?(s)

spec/ruby-enum/enum_spec.rb

@@ -432,8 +432,15 @@ class EmptyEnums
         expect(SubclassRedefiningParentKey.to_h).to eq(RED: 'crimson', GREEN: 'green')
       end
 
-      it 'includes both the parent and its own redefined value in values' do
-        expect(SubclassRedefiningParentKey.values).to eq(%w[red green crimson])
+      it "does not include the parent's overridden value, only its own redefined value, in values" do
+        expect(SubclassRedefiningParentKey.values).to eq(%w[crimson green])
+      end
+
+      it "does not recognize the parent's overridden value via value? or key" do
+        expect(SubclassRedefiningParentKey.value?('red')).to be false
+        expect(SubclassRedefiningParentKey.key('red')).to be_nil
+        expect(SubclassRedefiningParentKey.value?('crimson')).to be true
+        expect(SubclassRedefiningParentKey.key('crimson')).to eq :RED
       end
 
       it "the parent class' own value is unaffected" do