[rubygems/rubygems] util/rubocop -A --only Style/SelfAssignment

https://github.com/rubygems/rubygems/commit/7c1168c623

lib/rubygems/package.rb

@@ -58,7 +58,7 @@ class Gem::Package
       if source
         @path = source.path
 
-        message = message + " in #{path}" if path
+        message += " in #{path}" if path
       end
 
       super message

lib/rubygems/resolver/best_set.rb

@@ -60,7 +60,7 @@ class Gem::Resolver::BestSet < Gem::Resolver::ComposedSet
   def replace_failed_api_set(error) # :nodoc:
     uri = error.original_uri
     uri = URI uri unless URI === uri
-    uri = uri + "."
+    uri += "."
 
     raise error unless api_set = @sets.find do |set|
       Gem::Resolver::APISet === set && set.dep_uri == uri