pieces: show source file [broken WIP]

[igneus]

I can't find how to make loading a belongs_to association work. A call to PieceRepository#find_with_source_file results in a crash:

Boot Error

Something went wrong while loading /home/igneus/src/ruby/db.inadiutorium/config.ru
ROM::Registry::ElementNotFoundError: :source_files doesn't exist in ROM::RelationRegistry registry

/home/igneus/.rvm/gems/ruby-2.3.1/gems/rom-support-2.0.0/lib/rom/support/registry.rb:33:in `block in fetch'
/home/igneus/.rvm/gems/ruby-2.3.1/gems/rom-support-2.0.0/lib/rom/support/registry.rb:30:in `fetch'
/home/igneus/.rvm/gems/ruby-2.3.1/gems/rom-support-2.0.0/lib/rom/support/registry.rb:30:in `fetch'
/home/igneus/.rvm/gems/ruby-2.3.1/gems/rom-repository-0.3.1/lib/rom/repository/relation_proxy/combine.rb:219:in `combine_opts_for_assoc'
/home/igneus/.rvm/gems/ruby-2.3.1/gems/rom-repository-0.3.1/lib/rom/repository/relation_proxy/combine.rb:63:in `block in combine'
/home/igneus/.rvm/gems/ruby-2.3.1/gems/rom-repository-0.3.1/lib/rom/repository/relation_proxy/combine.rb:59:in `each'
/home/igneus/.rvm/gems/ruby-2.3.1/gems/rom-repository-0.3.1/lib/rom/repository/relation_proxy/combine.rb:59:in `combine'
/home/igneus/.rvm/gems/ruby-2.3.1/gems/rom-repository-0.3.1/lib/rom/repository/root.rb:76:in `aggregate'
/home/igneus/src/ruby/db.inadiutorium/lib/db.inadiutorium/repositories/piece_repository.rb:11:in `find_with_source_file'
/home/igneus/src/ruby/db.inadiutorium/apps/web/controllers/pieces/show.rb:9:in `call'
/home/igneus/.rvm/gems/ruby-2.3.1/gems/hanami-controller-0.8.1/lib/hanami/action/callbacks.rb:195:in `call'
/home/igneus/.rvm/gems/ruby-2.3.1/gems/hanami-controller-0.8.1/lib/hanami/action/callable.rb:71:in `block in call'
/home/igneus/.rvm/gems/ruby-2.3.1/gems/hanami-controller-0.8.1/lib/hanami/action/throwable.rb:143:in `block in _rescue'
/home/igneus/.rvm/gems/ruby-2.3.1/gems/hanami-controller-0.8.1/lib/hanami/action/throwable.rb:141:in `catch'
/home/igneus/.rvm/gems/ruby-2.3.1/gems/hanami-controller-0.8.1/lib/hanami/action/throwable.rb:141:in `_rescue'
/home/igneus/.rvm/gems/ruby-2.3.1/gems/hanami-controller-0.8.1/lib/hanami/action/callable.rb:67:in `call'
/home/igneus/.rvm/gems/ruby-2.3.1/gems/hanami-router-0.8.1/lib/hanami/routing/endpoint.rb:81:in `call'
/home/igneus/.rvm/gems/ruby-2.3.1/gems/http_router-0.11.2/lib/http_router.rb:193:in `process_destination_path'
(eval):211:in `call'
/home/igneus/.rvm/gems/ruby-2.3.1/gems/http_router-0.11.2/lib/http_router.rb:288:in `raw_call'
/home/igneus/.rvm/gems/ruby-2.3.1/gems/hanami-router-0.8.1/lib/hanami/routing/http_router.rb:155:in `raw_call'
/home/igneus/.rvm/gems/ruby-2.3.1/gems/http_router-0.11.2/lib/http_router.rb:142:in `call'
/home/igneus/.rvm/gems/ruby-2.3.1/gems/hanami-router-0.8.1/lib/hanami/router.rb:1007:in `call'
/home/igneus/.rvm/gems/ruby-2.3.1/gems/rack-1.6.5/lib/rack/builder.rb:153:in `call'
/home/igneus/.rvm/gems/ruby-2.3.1/gems/hanami-0.9.2/lib/hanami/middleware.rb:52:in `call'
/home/igneus/.rvm/gems/ruby-2.3.1/gems/hanami-0.9.2/lib/hanami/application.rb:180:in `call'
/home/igneus/.rvm/rubies/ruby-2.3.1/lib/ruby/2.3.0/delegate.rb:83:in `method_missing'
/home/igneus/.rvm/gems/ruby-2.3.1/gems/http_router-0.11.2/lib/http_router.rb:193:in `process_destination_path'
(eval):15:in `call'
/home/igneus/.rvm/gems/ruby-2.3.1/gems/http_router-0.11.2/lib/http_router.rb:288:in `raw_call'
/home/igneus/.rvm/gems/ruby-2.3.1/gems/hanami-router-0.8.1/lib/hanami/routing/http_router.rb:155:in `raw_call'
/home/igneus/.rvm/gems/ruby-2.3.1/gems/http_router-0.11.2/lib/http_router.rb:142:in `call'
/home/igneus/.rvm/gems/ruby-2.3.1/gems/hanami-router-0.8.1/lib/hanami/router.rb:1007:in `call'
/home/igneus/.rvm/gems/ruby-2.3.1/gems/rack-1.6.5/lib/rack/methodoverride.rb:22:in `call'
/home/igneus/.rvm/gems/ruby-2.3.1/gems/hanami-0.9.2/lib/hanami/assets/static.rb:49:in `call'
/home/igneus/.rvm/gems/ruby-2.3.1/gems/rack-1.6.5/lib/rack/builder.rb:153:in `call'
/home/igneus/.rvm/gems/ruby-2.3.1/gems/hanami-0.9.2/lib/hanami/app.rb:41:in `call'
/home/igneus/.rvm/gems/ruby-2.3.1/gems/shotgun-0.9.2/lib/shotgun/loader.rb:86:in `proceed_as_child'
/home/igneus/.rvm/gems/ruby-2.3.1/gems/shotgun-0.9.2/lib/shotgun/loader.rb:31:in `call!'
/home/igneus/.rvm/gems/ruby-2.3.1/gems/shotgun-0.9.2/lib/shotgun/loader.rb:18:in `call'
/home/igneus/.rvm/gems/ruby-2.3.1/gems/hanami-0.9.2/lib/hanami/assets/static.rb:49:in `call'
/home/igneus/.rvm/gems/ruby-2.3.1/gems/rack-1.6.5/lib/rack/lint.rb:49:in `_call'
/home/igneus/.rvm/gems/ruby-2.3.1/gems/rack-1.6.5/lib/rack/lint.rb:37:in `call'
/home/igneus/.rvm/gems/ruby-2.3.1/gems/rack-1.6.5/lib/rack/showexceptions.rb:24:in `call'
/home/igneus/.rvm/gems/ruby-2.3.1/gems/rack-1.6.5/lib/rack/commonlogger.rb:33:in `call'
/home/igneus/.rvm/gems/ruby-2.3.1/gems/rack-1.6.5/lib/rack/content_length.rb:15:in `call'
/home/igneus/.rvm/gems/ruby-2.3.1/gems/rack-1.6.5/lib/rack/handler/webrick.rb:88:in `service'
/home/igneus/.rvm/rubies/ruby-2.3.1/lib/ruby/2.3.0/webrick/httpserver.rb:140:in `service'
/home/igneus/.rvm/rubies/ruby-2.3.1/lib/ruby/2.3.0/webrick/httpserver.rb:96:in `run'
/home/igneus/.rvm/rubies/ruby-2.3.1/lib/ruby/2.3.0/webrick/server.rb:296:in `block in start_thread'