Exception with routes with dynamic :section

[florrain]

@LeFnord An issue for you.

This API:

class ObjectApi < Grape::API
  delete '/object/:id' do
    {}
  end
end

raises the following trace (custom API response but you get the idea):

{
  "error": "no implicit conversion of String into Hash",
  "backtrace": [
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/bundler/gems/grape-swagger-fdd70502b29d/lib/grape-swagger/endpoint.rb:199:in `merge'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/bundler/gems/grape-swagger-fdd70502b29d/lib/grape-swagger/endpoint.rb:199:in `block in params_object'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/bundler/gems/grape-swagger-fdd70502b29d/lib/grape-swagger/endpoint.rb:198:in `each'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/bundler/gems/grape-swagger-fdd70502b29d/lib/grape-swagger/endpoint.rb:198:in `map'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/bundler/gems/grape-swagger-fdd70502b29d/lib/grape-swagger/endpoint.rb:198:in `params_object'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/bundler/gems/grape-swagger-fdd70502b29d/lib/grape-swagger/endpoint.rb:135:in `method_object'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/bundler/gems/grape-swagger-fdd70502b29d/lib/grape-swagger/endpoint.rb:118:in `block in path_item'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/bundler/gems/grape-swagger-fdd70502b29d/lib/grape-swagger/endpoint.rb:96:in `each'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/bundler/gems/grape-swagger-fdd70502b29d/lib/grape-swagger/endpoint.rb:96:in `path_item'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/bundler/gems/grape-swagger-fdd70502b29d/lib/grape-swagger/endpoint.rb:80:in `block in path_and_definition_objects'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/bundler/gems/grape-swagger-fdd70502b29d/lib/grape-swagger/endpoint.rb:78:in `each'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/bundler/gems/grape-swagger-fdd70502b29d/lib/grape-swagger/endpoint.rb:78:in `path_and_definition_objects'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/bundler/gems/grape-swagger-fdd70502b29d/lib/grape-swagger/doc_methods.rb:45:in `block in setup'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/grape-0.15.0/lib/grape/endpoint.rb:66:in `call'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/grape-0.15.0/lib/grape/endpoint.rb:66:in `block (2 levels) in generate_api_method'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/activesupport-4.2.5.1/lib/active_support/notifications.rb:166:in `instrument'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/grape-0.15.0/lib/grape/endpoint.rb:65:in `block in generate_api_method'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/grape-0.15.0/lib/grape/endpoint.rb:249:in `block in run'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/activesupport-4.2.5.1/lib/active_support/notifications.rb:166:in `instrument'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/grape-0.15.0/lib/grape/endpoint.rb:230:in `run'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/grape-0.15.0/lib/grape/endpoint.rb:300:in `block in build_stack'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/grape-0.15.0/lib/grape/middleware/base.rb:30:in `call!'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/grape-0.15.0/lib/grape/middleware/base.rb:23:in `call'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/grape-0.15.0/lib/grape/middleware/base.rb:30:in `call!'",
    "/Users/flo/Dev/tup-shopping-cart-backend/app/api/middleware/jwt_parser.rb:9:in `call!'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/grape-0.15.0/lib/grape/middleware/base.rb:23:in `call'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/grape-middleware-logger-1.5.1/lib/grape/middleware/logger.rb:47:in `block in call!'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/grape-middleware-logger-1.5.1/lib/grape/middleware/logger.rb:45:in `catch'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/grape-middleware-logger-1.5.1/lib/grape/middleware/logger.rb:45:in `call!'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/grape-0.15.0/lib/grape/middleware/base.rb:23:in `call'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/grape-0.15.0/lib/grape/middleware/error.rb:29:in `block in call!'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/grape-0.15.0/lib/grape/middleware/error.rb:28:in `catch'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/grape-0.15.0/lib/grape/middleware/error.rb:28:in `call!'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/grape-0.15.0/lib/grape/middleware/base.rb:23:in `call'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/rack-1.6.4/lib/rack/head.rb:13:in `call'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/grape-0.15.0/lib/grape/endpoint.rb:214:in `call!'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/grape-0.15.0/lib/grape/endpoint.rb:208:in `call'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/rack-mount-0.8.3/lib/rack/mount/route_set.rb:152:in `block in call'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/rack-mount-0.8.3/lib/rack/mount/code_generation.rb:96:in `block in recognize'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/rack-mount-0.8.3/lib/rack/mount/code_generation.rb:68:in `optimized_each'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/rack-mount-0.8.3/lib/rack/mount/code_generation.rb:95:in `recognize'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/rack-mount-0.8.3/lib/rack/mount/route_set.rb:141:in `call'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/grape-0.15.0/lib/grape/api.rb:101:in `call'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/grape-0.15.0/lib/grape/api.rb:43:in `call!'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/grape-0.15.0/lib/grape/api.rb:38:in `call'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/actionpack-4.2.5.1/lib/action_dispatch/routing/mapper.rb:51:in `serve'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/actionpack-4.2.5.1/lib/action_dispatch/journey/router.rb:43:in `block in serve'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/actionpack-4.2.5.1/lib/action_dispatch/journey/router.rb:30:in `each'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/actionpack-4.2.5.1/lib/action_dispatch/journey/router.rb:30:in `serve'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/actionpack-4.2.5.1/lib/action_dispatch/routing/route_set.rb:815:in `call'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/rack-1.6.4/lib/rack/etag.rb:24:in `call'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/rack-1.6.4/lib/rack/conditionalget.rb:25:in `call'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/rack-1.6.4/lib/rack/head.rb:13:in `call'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/actionpack-4.2.5.1/lib/action_dispatch/middleware/params_parser.rb:27:in `call'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/actionpack-4.2.5.1/lib/action_dispatch/middleware/flash.rb:260:in `call'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/rack-1.6.4/lib/rack/session/abstract/id.rb:225:in `context'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/rack-1.6.4/lib/rack/session/abstract/id.rb:220:in `call'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/actionpack-4.2.5.1/lib/action_dispatch/middleware/cookies.rb:560:in `call'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/activerecord-4.2.5.1/lib/active_record/query_cache.rb:36:in `call'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/activerecord-4.2.5.1/lib/active_record/connection_adapters/abstract/connection_pool.rb:653:in `call'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/activerecord-4.2.5.1/lib/active_record/migration.rb:377:in `call'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/actionpack-4.2.5.1/lib/action_dispatch/middleware/callbacks.rb:29:in `block in call'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/activesupport-4.2.5.1/lib/active_support/callbacks.rb:88:in `__run_callbacks__'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/activesupport-4.2.5.1/lib/active_support/callbacks.rb:778:in `_run_call_callbacks'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/activesupport-4.2.5.1/lib/active_support/callbacks.rb:81:in `run_callbacks'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/actionpack-4.2.5.1/lib/action_dispatch/middleware/callbacks.rb:27:in `call'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/actionpack-4.2.5.1/lib/action_dispatch/middleware/reloader.rb:73:in `call'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/actionpack-4.2.5.1/lib/action_dispatch/middleware/remote_ip.rb:78:in `call'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/actionpack-4.2.5.1/lib/action_dispatch/middleware/debug_exceptions.rb:17:in `call'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/actionpack-4.2.5.1/lib/action_dispatch/middleware/show_exceptions.rb:30:in `call'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/railties-4.2.5.1/lib/rails/rack/logger.rb:38:in `call_app'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/railties-4.2.5.1/lib/rails/rack/logger.rb:20:in `block in call'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/activesupport-4.2.5.1/lib/active_support/tagged_logging.rb:68:in `block in tagged'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/activesupport-4.2.5.1/lib/active_support/tagged_logging.rb:26:in `tagged'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/activesupport-4.2.5.1/lib/active_support/tagged_logging.rb:68:in `tagged'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/railties-4.2.5.1/lib/rails/rack/logger.rb:20:in `call'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/actionpack-4.2.5.1/lib/action_dispatch/middleware/request_id.rb:21:in `call'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/rack-1.6.4/lib/rack/methodoverride.rb:22:in `call'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/rack-1.6.4/lib/rack/runtime.rb:18:in `call'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/activesupport-4.2.5.1/lib/active_support/cache/strategy/local_cache_middleware.rb:28:in `call'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/rack-1.6.4/lib/rack/lock.rb:17:in `call'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/actionpack-4.2.5.1/lib/action_dispatch/middleware/static.rb:116:in `call'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/rack-1.6.4/lib/rack/sendfile.rb:113:in `call'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/railties-4.2.5.1/lib/rails/engine.rb:518:in `call'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/railties-4.2.5.1/lib/rails/application.rb:165:in `call'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/rack-1.6.4/lib/rack/lock.rb:17:in `call'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/rack-1.6.4/lib/rack/content_length.rb:15:in `call'",
    "/Users/flo/.rvm/gems/ruby-2.3.0@shopping-cart/gems/rack-1.6.4/lib/rack/handler/webrick.rb:88:in `service'",
    "/Users/flo/.rvm/rubies/ruby-2.3.0/lib/ruby/2.3.0/webrick/httpserver.rb:140:in `service'",
    "/Users/flo/.rvm/rubies/ruby-2.3.0/lib/ruby/2.3.0/webrick/httpserver.rb:96:in `run'",
    "/Users/flo/.rvm/rubies/ruby-2.3.0/lib/ruby/2.3.0/webrick/server.rb:296:in `block in start_thread'"
  ]
}

No specific setup, this is the API definition:

  version "v1.0", using: :path do
    mount ObjectApi
  end

  add_swagger_documentation

Remove the :id and it works fine. I used Grape 0.14 and 0.15 and revision fdd70502b29d from the 2.0 branch.