From 46c2737982b3fc8f8b0dbe73f37d2a916f56e4aa Mon Sep 17 00:00:00 2001
From: Daniel Sager <daniel.sager@sager-software.eu>
Date: Tue, 17 Dec 2013 12:26:44 +0100
Subject: [PATCH 1/2] added failing spec: default values for grouped parameters

---
 spec/grape/validations/default_spec.rb | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/spec/grape/validations/default_spec.rb b/spec/grape/validations/default_spec.rb
index 9a49571aa0..c0afe7d462 100644
--- a/spec/grape/validations/default_spec.rb
+++ b/spec/grape/validations/default_spec.rb
@@ -40,6 +40,15 @@ class API < Grape::API
         get '/numbers' do
           { random_number: params[:random], non_random_number: params[:non_random_number] }
         end
+
+        params do
+          group :foo do
+            optional :bar, default: 'foo-bar'
+          end
+        end
+        get '/group' do
+          { foo_bar: params[:foo][:bar] }
+        end
       end
     end
   end
@@ -83,4 +92,11 @@ def app
     before['non_random_number'].should == after['non_random_number']
     before['random_number'].should_not == after['random_number']
   end
+
+  it 'set default values for optional grouped params' do
+    get('/group')
+    last_response.status.should == 200
+    last_response.body.should == { foo_bar: 'foo-bar' }.to_json
+  end
+
 end

From f5b87725befe3c14b28d9281a9abc8378e87b73d Mon Sep 17 00:00:00 2001
From: dm1try <dmitry.dedov@tut.by>
Date: Tue, 17 Dec 2013 23:57:46 +0300
Subject: [PATCH 2/2] Fix default values for grouped params

---
 CHANGELOG.md                     | 1 +
 lib/grape/validations/default.rb | 6 ++++--
 2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index be049eb138..302144d9d3 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -22,6 +22,7 @@ Next Release
 * [#500](https://github.com/intridea/grape/pull/500): Skip entity auto-detection when explicitely passed - [@yaneq](https://github.com/yaneq).
 * [#503](https://github.com/intridea/grape/pull/503): Calling declared(params) from child namespace fails to include parent namespace defined params - [@myitcv](https://github.com/myitcv).
 * [#512](https://github.com/intridea/grape/pull/512): Don't create `Grape::Request` multiple times - [@dblock](https://github.com/dblock).
+* [#538](https://github.com/intridea/grape/pull/538): Fix default values for grouped params - [@dm1try](https://github.com/dm1try).
 * Your contribution here.
 
 
diff --git a/lib/grape/validations/default.rb b/lib/grape/validations/default.rb
index b48a0753e2..63018e3e84 100644
--- a/lib/grape/validations/default.rb
+++ b/lib/grape/validations/default.rb
@@ -11,10 +11,12 @@ def validate_param!(attr_name, params)
       end
 
       def validate!(params)
-        params = AttributesIterator.new(self, @scope, params)
-        params.each do |resource_params, attr_name|
+        attrs = AttributesIterator.new(self, @scope, params)
+        parent_element = @scope.element
+        attrs.each do |resource_params, attr_name|
           if resource_params[attr_name].nil?
             validate_param!(attr_name, resource_params)
+            params[parent_element] = resource_params if parent_element
           end
         end
       end