1 files changed, 20 insertions, 0 deletions
diff --git a/lib/api/helpers/common_helpers.rb b/lib/api/helpers/common_helpers.rb
index 32a15381f27..a44fd4b0a5b 100644
--- a/lib/api/helpers/common_helpers.rb
+++ b/lib/api/helpers/common_helpers.rb
@@ -12,6 +12,26 @@ module API
           end
         end
       end
+
+      # Grape v1.3.3 no longer automatically coerces an Array
+      # type to an empty array if the value is nil.
+      def coerce_nil_params_to_array!
+        keys_to_coerce = params_with_array_types
+
+        params.each do |key, val|
+          params[key] = Array(val) if val.nil? && keys_to_coerce.include?(key)
+        end
+      end
+
+      def params_with_array_types
+        options[:route_options][:params].map do |key, val|
+          param_type = val[:type]
+          # Search for parameters with Array types (e.g. "[String]", "[Integer]", etc.)
+          if param_type =~ %r(\[\w*\])
+            key
+          end
+        end.compact.to_set
+      end
     end
   end
 end