MetadataDrop: update mutations reference to use helper method

parkr · parkr · commit 6b4073d4b67d · 2019-10-02T11:53:56.000-04:00
diff --git a/lib/jekyll-github-metadata/metadata_drop.rb b/lib/jekyll-github-metadata/metadata_drop.rb
@@ -14,7 +14,7 @@ class MetadataDrop < Jekyll::Drops::Drop
       alias_method :invoke_drop, :[]
       def key?(key)
         return false if key.nil?
-        return true if self.class.mutable? && @mutations.key?(key)
+        return true if self.class.mutable? && mutations.key?(key)
 
         respond_to?(key) || fallback_data.key?(key)
       end
@@ -95,6 +95,10 @@ def build_revision
       def fallback_data
         @fallback_data ||= {}
       end
+
+      def mutations
+        @mutations ||= {}
+      end
     end
   end
 end
