Merge pull request #2014 from ericproulx/reduced_retained_array

Reduced array allocation

Author: dblock

CHANGELOG.md

@@ -1,7 +1,8 @@
 ### 1.3.2 (Next)
 
 #### Features
-
+* Your contribution here.
+* [#2014](https://github.com/ruby-grape/grape/pull/2014): Reduce total allocated arrays - [@ericproulx](https://github.com/ericproulx).
 * [#2011](https://github.com/ruby-grape/grape/pull/2011): Reduce total retained regexes - [@ericproulx](https://github.com/ericproulx).
 
 #### Fixes

lib/grape/util/reverse_stackable_values.rb

@@ -8,8 +8,10 @@ class ReverseStackableValues < StackableValues
       protected
 
       def concat_values(inherited_value, new_value)
+        return inherited_value unless new_value
+
         [].tap do |value|
-          value.concat(new_value) if new_value
+          value.concat(new_value)
           value.concat(inherited_value)
         end
       end

lib/grape/util/stackable_values.rb

@@ -29,9 +29,11 @@ def to_hash
       protected
 
       def concat_values(inherited_value, new_value)
+        return inherited_value unless new_value
+
         [].tap do |value|
           value.concat(inherited_value)
-          value.concat(new_value) if new_value
+          value.concat(new_value)
         end
       end
     end