Nested with support

lib/grape/dsl/parameters.rb

@@ -170,7 +170,8 @@ def optional(*attrs, &block)
       # @param (see #requires)
       # @option (see #requires)
       def with(*attrs, &block)
-        new_group_scope(attrs.clone, &block)
+        new_group_attrs = [@group, attrs.clone.first].compact.reduce(&:deep_merge)
+        new_group_scope([new_group_attrs], &block)
       end
 
       # Disallow the given parameters to be present in the same request.

spec/grape/dsl/parameters_spec.rb

@@ -35,6 +35,12 @@ def validates_reader
           @validates
         end
 
+        def new_scope(args, _, &block)
+          nested_scope = self.class.new
+          nested_scope.new_group_scope(args, &block)
+          nested_scope
+        end
+
         def new_group_scope(args)
           @group = args.clone.first
           yield
@@ -169,6 +175,37 @@ def extract_message_option(attrs)
             ]
           )
         end
+
+        it "supports nested 'with' calls" do
+          subject.with(type: Integer, documentation: { in: 'body' }) do
+            subject.optional :pipboy_id
+            subject.with(documentation: { default: 33 }) do
+              subject.optional :vault
+            end
+          end
+
+          expect(subject.validate_attributes_reader).to eq(
+            [
+              [:pipboy_id], { type: Integer, documentation: { in: 'body' } },
+              [:vault], { type: Integer, documentation: { in: 'body', default: 33 } }
+            ]
+          )
+        end
+
+        it "supports Hash parameter inside the 'with' calls" do
+          subject.with(documentation: { in: 'body' }) do
+            subject.optional :info, type: Hash, documentation: { x: { nullable: true }, desc: 'The info' } do
+              subject.optional :vault, type: Integer, documentation: { default: 33, desc: 'The vault number' }
+            end
+          end
+
+          expect(subject.validate_attributes_reader).to eq(
+            [
+              [:info], { type: Hash, documentation: { in: 'body', desc: 'The info', x: { nullable: true } } },
+              [:vault], { type: Integer, documentation: { in: 'body', default: 33, desc: 'The vault number' } }
+            ]
+          )
+        end
       end
 
       describe '#mutually_exclusive' do