diff --git a/spec/mosaik/syntax/tree_spec.rb b/spec/mosaik/syntax/tree_spec.rb
index 0717383..f3df62f 100644
--- a/spec/mosaik/syntax/tree_spec.rb
+++ b/spec/mosaik/syntax/tree_spec.rb
@@ -53,8 +53,7 @@
       tree["Foo::Bar"]
       tree["Foo::Baz::Bat"]
 
-      constants = []
-      tree.each { |constant| constants << constant.name }
+      constants = tree.map(&:name)
 
       expect(constants).to eq ["Foo", "Foo::Bar", "Foo::Baz", "Foo::Baz::Bat"]
     end