From f627044ce1866ace962aeace13dc8d4d578699ce Mon Sep 17 00:00:00 2001
From: fsainz <167863+fsainz@users.noreply.github.com>
Date: Tue, 19 Jan 2021 14:20:13 +0100
Subject: [PATCH 1/2] fixes configuration inside namespaced params scope

---
 lib/grape/validations/params_scope.rb |  2 +-
 spec/grape/api_remount_spec.rb        | 13 +++++++++----
 2 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/lib/grape/validations/params_scope.rb b/lib/grape/validations/params_scope.rb
index 792762b06a..a39383d5dd 100644
--- a/lib/grape/validations/params_scope.rb
+++ b/lib/grape/validations/params_scope.rb
@@ -39,7 +39,7 @@ def initialize(opts, &block)
       end
 
       def configuration
-        @api.configuration.evaluate
+        @api.configuration.respond_to?(:evaluate) ? @api.configuration.evaluate : @api.configuration
       end
 
       # @return [Boolean] whether or not this entire scope needs to be
diff --git a/spec/grape/api_remount_spec.rb b/spec/grape/api_remount_spec.rb
index 2f75017654..ff764293cd 100644
--- a/spec/grape/api_remount_spec.rb
+++ b/spec/grape/api_remount_spec.rb
@@ -340,19 +340,24 @@ def app
       context 'when the configuration is read within a namespace' do
         before do
           a_remounted_api.namespace 'api' do
+            params do
+              requires configuration[:required_param]
+            end
             get "/#{configuration[:path]}" do
               '10 votes'
             end
           end
-          root_api.mount a_remounted_api, with: { path: 'votes' }
-          root_api.mount a_remounted_api, with: { path: 'scores' }
+          root_api.mount a_remounted_api, with: { path: 'votes', required_param: 'param_key' }
+          root_api.mount a_remounted_api, with: { path: 'scores', required_param: 'param_key' }
         end
 
         it 'will use the dynamic configuration on all routes' do
-          get 'api/votes'
+          get 'api/votes', param_key: 'a'
           expect(last_response.body).to eql '10 votes'
-          get 'api/scores'
+          get 'api/scores', param_key: 'a'
           expect(last_response.body).to eql '10 votes'
+          get 'api/votes'
+          expect(last_response.status).to eq 400
         end
       end
 

From a55dee930a4b7a2979b4f01247c908130d8f70fc Mon Sep 17 00:00:00 2001
From: fsainz <167863+fsainz@users.noreply.github.com>
Date: Mon, 25 Jan 2021 08:24:26 +0100
Subject: [PATCH 2/2] adds changlog line

---
 CHANGELOG.md | 1 +
 1 file changed, 1 insertion(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index ad0462bf93..ad32abbc99 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -13,6 +13,7 @@
 * [#2137](https://github.com/ruby-grape/grape/pull/2137): Fix typos - [@johnny-miyake](https://github.com/johnny-miyake).
 * [#2131](https://github.com/ruby-grape/grape/pull/2131): Fix Ruby 2.7 keyword deprecation warning in validators/coerce - [@K0H205](https://github.com/K0H205).
 * [#2132](https://github.com/ruby-grape/grape/pull/2132): Use #ruby2_keywords for correct delegation on Ruby <= 2.6, 2.7 and 3 - [@eregon](https://github.com/eregon).
+* [#2152](https://github.com/ruby-grape/grape/pull/2152): Fix configuration method inside namespaced params - [@fsainz](https://github.com/fsainz).
 
 ### 1.5.1 (2020/11/15)