rails / sass-rails

Ruby on Rails stylesheet engine for Sass

Geek Repo:Geek Repo

Github PK Tool:Github PK Tool

Can't modify frozen Array

bvogel opened this issue · comments

Hi,
from version 5.0.2 onwards I'm having an issue with sass:

RuntimeError - can't modify frozen Array
  (in /Users/bvogel/Development/buddy/app/assets/stylesheets/application.scss.erb):
  modular-scale (1.0.6) lib/modular-scale.rb:118:in `trim_list'
  sass (3.4.13) lib/sass/script/tree/funcall.rb:140:in `_perform'
  sass (3.4.13) lib/sass/script/tree/node.rb:50:in `perform'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:468:in `visit_variable'
  sass (3.4.13) lib/sass/tree/visitors/base.rb:36:in `visit'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:158:in `block in visit'
  sass (3.4.13) lib/sass/stack.rb:79:in `block in with_base'
  sass (3.4.13) lib/sass/stack.rb:115:in `with_frame'
  sass (3.4.13) lib/sass/stack.rb:79:in `with_base'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:158:in `visit'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:299:in `block (2 levels) in visit_if'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:299:in `block in visit_if'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:179:in `with_environment'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:298:in `visit_if'
  sass (3.4.13) lib/sass/tree/visitors/base.rb:36:in `visit'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:158:in `block in visit'
  sass (3.4.13) lib/sass/stack.rb:79:in `block in with_base'
  sass (3.4.13) lib/sass/stack.rb:115:in `with_frame'
  sass (3.4.13) lib/sass/stack.rb:79:in `with_base'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:158:in `visit'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:8:in `visit'
  sass (3.4.13) lib/sass/script/tree/funcall.rb:248:in `block (3 levels) in perform_sass_fn'
  sass (3.4.13) lib/sass/script/tree/funcall.rb:248:in `block (2 levels) in perform_sass_fn'
  sass (3.4.13) lib/sass/script/tree/funcall.rb:247:in `block in perform_sass_fn'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:84:in `perform_arguments'
  sass (3.4.13) lib/sass/script/tree/funcall.rb:244:in `perform_sass_fn'
  sass (3.4.13) lib/sass/script/tree/funcall.rb:131:in `_perform'
  sass (3.4.13) lib/sass/script/tree/node.rb:50:in `perform'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:402:in `visit_return'
  sass (3.4.13) lib/sass/tree/visitors/base.rb:36:in `visit'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:158:in `block in visit'
  sass (3.4.13) lib/sass/stack.rb:79:in `block in with_base'
  sass (3.4.13) lib/sass/stack.rb:115:in `with_frame'
  sass (3.4.13) lib/sass/stack.rb:79:in `with_base'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:158:in `visit'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:8:in `visit'
  sass (3.4.13) lib/sass/script/tree/funcall.rb:248:in `block (3 levels) in perform_sass_fn'
  sass (3.4.13) lib/sass/script/tree/funcall.rb:248:in `block (2 levels) in perform_sass_fn'
  sass (3.4.13) lib/sass/script/tree/funcall.rb:247:in `block in perform_sass_fn'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:84:in `perform_arguments'
  sass (3.4.13) lib/sass/script/tree/funcall.rb:244:in `perform_sass_fn'
  sass (3.4.13) lib/sass/script/tree/funcall.rb:131:in `_perform'
  sass (3.4.13) lib/sass/script/tree/node.rb:50:in `perform'
  sass (3.4.13) lib/sass/script/tree/funcall.rb:170:in `perform_arg'
  sass (3.4.13) lib/sass/script/tree/funcall.rb:124:in `block in _perform'
  sass (3.4.13) lib/sass/script/tree/funcall.rb:124:in `_perform'
  sass (3.4.13) lib/sass/script/tree/node.rb:50:in `perform'
  sass (3.4.13) lib/sass/script/tree/operation.rb:64:in `_perform'
  sass (3.4.13) lib/sass/script/tree/node.rb:50:in `perform'
  sass (3.4.13) lib/sass/script/tree/operation.rb:64:in `_perform'
  sass (3.4.13) lib/sass/script/tree/node.rb:50:in `perform'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:297:in `visit_if'
  sass (3.4.13) lib/sass/tree/visitors/base.rb:36:in `visit'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:158:in `block in visit'
  sass (3.4.13) lib/sass/stack.rb:79:in `block in with_base'
  sass (3.4.13) lib/sass/stack.rb:115:in `with_frame'
  sass (3.4.13) lib/sass/stack.rb:79:in `with_base'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:158:in `visit'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:299:in `block (2 levels) in visit_if'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:299:in `block in visit_if'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:179:in `with_environment'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:298:in `visit_if'
  sass (3.4.13) lib/sass/tree/visitors/base.rb:36:in `visit'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:158:in `block in visit'
  sass (3.4.13) lib/sass/stack.rb:79:in `block in with_base'
  sass (3.4.13) lib/sass/stack.rb:115:in `with_frame'
  sass (3.4.13) lib/sass/stack.rb:79:in `with_base'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:158:in `visit'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:8:in `visit'
  sass (3.4.13) lib/sass/script/tree/funcall.rb:248:in `block (3 levels) in perform_sass_fn'
  sass (3.4.13) lib/sass/script/tree/funcall.rb:248:in `block (2 levels) in perform_sass_fn'
  sass (3.4.13) lib/sass/script/tree/funcall.rb:247:in `block in perform_sass_fn'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:84:in `perform_arguments'
  sass (3.4.13) lib/sass/script/tree/funcall.rb:244:in `perform_sass_fn'
  sass (3.4.13) lib/sass/script/tree/funcall.rb:131:in `_perform'
  sass (3.4.13) lib/sass/script/tree/node.rb:50:in `perform'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:402:in `visit_return'
  sass (3.4.13) lib/sass/tree/visitors/base.rb:36:in `visit'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:158:in `block in visit'
  sass (3.4.13) lib/sass/stack.rb:79:in `block in with_base'
  sass (3.4.13) lib/sass/stack.rb:115:in `with_frame'
  sass (3.4.13) lib/sass/stack.rb:79:in `with_base'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:158:in `visit'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:8:in `visit'
  sass (3.4.13) lib/sass/script/tree/funcall.rb:248:in `block (3 levels) in perform_sass_fn'
  sass (3.4.13) lib/sass/script/tree/funcall.rb:248:in `block (2 levels) in perform_sass_fn'
  sass (3.4.13) lib/sass/script/tree/funcall.rb:247:in `block in perform_sass_fn'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:84:in `perform_arguments'
  sass (3.4.13) lib/sass/script/tree/funcall.rb:244:in `perform_sass_fn'
  sass (3.4.13) lib/sass/script/tree/funcall.rb:131:in `_perform'
  sass (3.4.13) lib/sass/script/tree/node.rb:50:in `perform'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:394:in `visit_prop'
  sass (3.4.13) lib/sass/tree/visitors/base.rb:36:in `visit'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:158:in `block in visit'
  sass (3.4.13) lib/sass/stack.rb:79:in `block in with_base'
  sass (3.4.13) lib/sass/stack.rb:115:in `with_frame'
  sass (3.4.13) lib/sass/stack.rb:79:in `with_base'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:158:in `visit'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:430:in `block (2 levels) in visit_rule'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:430:in `block in visit_rule'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:179:in `with_environment'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:428:in `visit_rule'
  sass (3.4.13) lib/sass/tree/visitors/base.rb:36:in `visit'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:158:in `block in visit'
  sass (3.4.13) lib/sass/stack.rb:79:in `block in with_base'
  sass (3.4.13) lib/sass/stack.rb:115:in `with_frame'
  sass (3.4.13) lib/sass/stack.rb:79:in `with_base'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:158:in `visit'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:325:in `block (2 levels) in visit_import'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:325:in `block in visit_import'
  sass (3.4.13) lib/sass/stack.rb:88:in `block in with_import'
  sass (3.4.13) lib/sass/stack.rb:115:in `with_frame'
  sass (3.4.13) lib/sass/stack.rb:88:in `with_import'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:322:in `visit_import'
  sass (3.4.13) lib/sass/tree/visitors/base.rb:36:in `visit'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:158:in `block in visit'
  sass (3.4.13) lib/sass/stack.rb:79:in `block in with_base'
  sass (3.4.13) lib/sass/stack.rb:115:in `with_frame'
  sass (3.4.13) lib/sass/stack.rb:79:in `with_base'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:158:in `visit'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:325:in `block (2 levels) in visit_import'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:325:in `block in visit_import'
  sass (3.4.13) lib/sass/stack.rb:88:in `block in with_import'
  sass (3.4.13) lib/sass/stack.rb:115:in `with_frame'
  sass (3.4.13) lib/sass/stack.rb:88:in `with_import'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:322:in `visit_import'
  sass (3.4.13) lib/sass/tree/visitors/base.rb:36:in `visit'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:158:in `block in visit'
  sass (3.4.13) lib/sass/stack.rb:79:in `block in with_base'
  sass (3.4.13) lib/sass/stack.rb:115:in `with_frame'
  sass (3.4.13) lib/sass/stack.rb:79:in `with_base'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:158:in `visit'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:325:in `block (2 levels) in visit_import'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:325:in `block in visit_import'
  sass (3.4.13) lib/sass/stack.rb:88:in `block in with_import'
  sass (3.4.13) lib/sass/stack.rb:115:in `with_frame'
  sass (3.4.13) lib/sass/stack.rb:88:in `with_import'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:322:in `visit_import'
  sass (3.4.13) lib/sass/tree/visitors/base.rb:36:in `visit'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:158:in `block in visit'
  sass (3.4.13) lib/sass/stack.rb:79:in `block in with_base'
  sass (3.4.13) lib/sass/stack.rb:115:in `with_frame'
  sass (3.4.13) lib/sass/stack.rb:79:in `with_base'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:158:in `visit'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:325:in `block (2 levels) in visit_import'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:325:in `block in visit_import'
  sass (3.4.13) lib/sass/stack.rb:88:in `block in with_import'
  sass (3.4.13) lib/sass/stack.rb:115:in `with_frame'
  sass (3.4.13) lib/sass/stack.rb:88:in `with_import'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:322:in `visit_import'
  sass (3.4.13) lib/sass/tree/visitors/base.rb:36:in `visit'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:158:in `block in visit'
  sass (3.4.13) lib/sass/stack.rb:79:in `block in with_base'
  sass (3.4.13) lib/sass/stack.rb:115:in `with_frame'
  sass (3.4.13) lib/sass/stack.rb:79:in `with_base'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:158:in `visit'
  sass (3.4.13) lib/sass/tree/visitors/base.rb:52:in `block in visit_children'
  sass (3.4.13) lib/sass/tree/visitors/base.rb:52:in `visit_children'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:167:in `block in visit_children'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:179:in `with_environment'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:166:in `visit_children'
  sass (3.4.13) lib/sass/tree/visitors/base.rb:36:in `block in visit'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:186:in `visit_root'
  sass (3.4.13) lib/sass/tree/visitors/base.rb:36:in `visit'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:157:in `visit'
  sass (3.4.13) lib/sass/tree/visitors/perform.rb:8:in `visit'
  sass (3.4.13) lib/sass/tree/root_node.rb:36:in `css_tree'
  sass (3.4.13) lib/sass/tree/root_node.rb:20:in `render'
  sass (3.4.13) lib/sass/engine.rb:268:in `render'
  compass-rails (2.0.4) lib/compass-rails/patches/sass_importer.rb:48:in `evaluate'
  tilt (1.4.1) lib/tilt/template.rb:103:in `render'
  sprockets (2.12.3) lib/sprockets/context.rb:197:in `block in evaluate'
  sprockets (2.12.3) lib/sprockets/context.rb:194:in `evaluate'
  sprockets (2.12.3) lib/sprockets/processed_asset.rb:12:in `initialize'
  sprockets (2.12.3) lib/sprockets/base.rb:374:in `block in build_asset'
  sprockets (2.12.3) lib/sprockets/base.rb:395:in `circular_call_protection'
  sprockets (2.12.3) lib/sprockets/base.rb:373:in `build_asset'
  sprockets (2.12.3) lib/sprockets/index.rb:94:in `block in build_asset'
  sprockets (2.12.3) lib/sprockets/caching.rb:58:in `cache_asset'
  sprockets (2.12.3) lib/sprockets/index.rb:93:in `build_asset'
  sprockets (2.12.3) lib/sprockets/base.rb:287:in `find_asset'
  sprockets (2.12.3) lib/sprockets/index.rb:61:in `find_asset'
  sprockets (2.12.3) lib/sprockets/bundled_asset.rb:16:in `initialize'
  sprockets (2.12.3) lib/sprockets/base.rb:377:in `build_asset'
  sprockets (2.12.3) lib/sprockets/index.rb:94:in `block in build_asset'
  sprockets (2.12.3) lib/sprockets/caching.rb:58:in `cache_asset'
  sprockets (2.12.3) lib/sprockets/index.rb:93:in `build_asset'
  sprockets (2.12.3) lib/sprockets/base.rb:287:in `find_asset'
  sprockets (2.12.3) lib/sprockets/index.rb:61:in `find_asset'
  sprockets (2.12.3) lib/sprockets/environment.rb:75:in `find_asset'
  sprockets (2.12.3) lib/sprockets/base.rb:295:in `[]'
  sprockets-rails (2.3.0) lib/sprockets/rails/helper.rb:243:in `lookup_asset_for_path'
  sprockets-rails (2.3.0) lib/sprockets/rails/helper.rb:173:in `block in stylesheet_link_tag'
  sprockets-rails (2.3.0) lib/sprockets/rails/helper.rb:171:in `stylesheet_link_tag'
  app/views/layouts/application.html.haml:8:in `_app_views_layouts_application_html_haml__1619704298570112141_70184241961600'
  actionview (4.2.1) lib/action_view/template.rb:145:in `block in render'
  activesupport (4.2.1) lib/active_support/notifications.rb:166:in `instrument'
  actionview (4.2.1) lib/action_view/template.rb:333:in `instrument'
  actionview (4.2.1) lib/action_view/template.rb:143:in `render'
  rack-mini-profiler (0.9.3) lib/mini_profiler/profiling_methods.rb:106:in `block in profile_method'
  actionview (4.2.1) lib/action_view/renderer/template_renderer.rb:66:in `render_with_layout'
  actionview (4.2.1) lib/action_view/renderer/template_renderer.rb:52:in `render_template'
  actionview (4.2.1) lib/action_view/renderer/template_renderer.rb:14:in `render'
  actionview (4.2.1) lib/action_view/renderer/renderer.rb:42:in `render_template'
  actionview (4.2.1) lib/action_view/renderer/renderer.rb:23:in `render'
  actionview (4.2.1) lib/action_view/rendering.rb:100:in `_render_template'
  actionpack (4.2.1) lib/action_controller/metal/streaming.rb:217:in `_render_template'
  actionview (4.2.1) lib/action_view/rendering.rb:83:in `render_to_body'
  actionpack (4.2.1) lib/action_controller/metal/rendering.rb:32:in `render_to_body'
  actionpack (4.2.1) lib/action_controller/metal/renderers.rb:37:in `render_to_body'
  actionpack (4.2.1) lib/abstract_controller/rendering.rb:25:in `render'
  actionpack (4.2.1) lib/action_controller/metal/rendering.rb:16:in `render'
  actionpack (4.2.1) lib/action_controller/metal/instrumentation.rb:44:in `block (2 levels) in render'
  activesupport (4.2.1) lib/active_support/core_ext/benchmark.rb:12:in `block in ms'
  /Users/bvogel/.rvm/rubies/ruby-2.2.1/lib/ruby/2.2.0/benchmark.rb:303:in `realtime'
  activesupport (4.2.1) lib/active_support/core_ext/benchmark.rb:12:in `ms'
  actionpack (4.2.1) lib/action_controller/metal/instrumentation.rb:44:in `block in render'
  actionpack (4.2.1) lib/action_controller/metal/instrumentation.rb:87:in `cleanup_view_runtime'
  activerecord (4.2.1) lib/active_record/railties/controller_runtime.rb:25:in `cleanup_view_runtime'
  actionpack (4.2.1) lib/action_controller/metal/instrumentation.rb:43:in `render'
  remotipart (1.2.1) lib/remotipart/render_overrides.rb:14:in `render_with_remotipart'
  app/controllers/article_tracker/articles_controller.rb:82:in `search'
  actionpack (4.2.1) lib/action_controller/metal/implicit_render.rb:4:in `send_action'
  actionpack (4.2.1) lib/abstract_controller/base.rb:198:in `process_action'
  actionpack (4.2.1) lib/action_controller/metal/rendering.rb:10:in `process_action'
  actionpack (4.2.1) lib/abstract_controller/callbacks.rb:20:in `block in process_action'
  activesupport (4.2.1) lib/active_support/callbacks.rb:117:in `call'
  activesupport (4.2.1) lib/active_support/callbacks.rb:555:in `block (2 levels) in compile'
  activesupport (4.2.1) lib/active_support/callbacks.rb:505:in `call'
  activesupport (4.2.1) lib/active_support/callbacks.rb:92:in `_run_callbacks'
  activesupport (4.2.1) lib/active_support/callbacks.rb:776:in `_run_process_action_callbacks'
  activesupport (4.2.1) lib/active_support/callbacks.rb:81:in `run_callbacks'
  actionpack (4.2.1) lib/abstract_controller/callbacks.rb:19:in `process_action'
  actionpack (4.2.1) lib/action_controller/metal/rescue.rb:29:in `process_action'
  actionpack (4.2.1) lib/action_controller/metal/instrumentation.rb:32:in `block in process_action'
  activesupport (4.2.1) lib/active_support/notifications.rb:164:in `block in instrument'
  activesupport (4.2.1) lib/active_support/notifications/instrumenter.rb:20:in `instrument'
  activesupport (4.2.1) lib/active_support/notifications.rb:164:in `instrument'
  actionpack (4.2.1) lib/action_controller/metal/instrumentation.rb:30:in `process_action'
  actionpack (4.2.1) lib/action_controller/metal/params_wrapper.rb:250:in `process_action'
  activerecord (4.2.1) lib/active_record/railties/controller_runtime.rb:18:in `process_action'
  actionpack (4.2.1) lib/abstract_controller/base.rb:137:in `process'
  actionview (4.2.1) lib/action_view/rendering.rb:30:in `process'
  rack-mini-profiler (0.9.3) lib/mini_profiler/profiling_methods.rb:106:in `block in profile_method'
  actionpack (4.2.1) lib/action_controller/metal.rb:196:in `dispatch'
  actionpack (4.2.1) lib/action_controller/metal/rack_delegation.rb:13:in `dispatch'
  actionpack (4.2.1) lib/action_controller/metal.rb:237:in `block in action'
  actionpack (4.2.1) lib/action_dispatch/routing/route_set.rb:74:in `dispatch'
  actionpack (4.2.1) lib/action_dispatch/routing/route_set.rb:43:in `serve'
  actionpack (4.2.1) lib/action_dispatch/journey/router.rb:43:in `block in serve'
  actionpack (4.2.1) lib/action_dispatch/journey/router.rb:30:in `serve'
  actionpack (4.2.1) lib/action_dispatch/routing/route_set.rb:819:in `call'
  bullet (4.14.7) lib/bullet/rack.rb:12:in `call'
  rack (1.6.1) lib/rack/etag.rb:24:in `call'
  rack (1.6.1) lib/rack/conditionalget.rb:25:in `call'
  rack (1.6.1) lib/rack/head.rb:13:in `call'
  remotipart (1.2.1) lib/remotipart/middleware.rb:27:in `call'
  actionpack (4.2.1) lib/action_dispatch/middleware/params_parser.rb:27:in `call'
  actionpack (4.2.1) lib/action_dispatch/middleware/flash.rb:260:in `call'
  rack (1.6.1) lib/rack/session/abstract/id.rb:225:in `context'
  rack (1.6.1) lib/rack/session/abstract/id.rb:220:in `call'
  actionpack (4.2.1) lib/action_dispatch/middleware/cookies.rb:560:in `call'
  activerecord (4.2.1) lib/active_record/query_cache.rb:36:in `call'
  activerecord (4.2.1) lib/active_record/connection_adapters/abstract/connection_pool.rb:649:in `call'
  actionpack (4.2.1) lib/action_dispatch/middleware/callbacks.rb:29:in `block in call'
  activesupport (4.2.1) lib/active_support/callbacks.rb:88:in `_run_callbacks'
  activesupport (4.2.1) lib/active_support/callbacks.rb:776:in `_run_call_callbacks'
  activesupport (4.2.1) lib/active_support/callbacks.rb:81:in `run_callbacks'
  actionpack (4.2.1) lib/action_dispatch/middleware/callbacks.rb:27:in `call'
  actionpack (4.2.1) lib/action_dispatch/middleware/reloader.rb:73:in `call'
  actionpack (4.2.1) lib/action_dispatch/middleware/remote_ip.rb:78:in `call'
  airbrake (4.1.0) lib/airbrake/rails/middleware.rb:13:in `call'
  better_errors (2.1.1) lib/better_errors/middleware.rb:84:in `protected_app_call'
  better_errors (2.1.1) lib/better_errors/middleware.rb:79:in `better_errors_call'
  better_errors (2.1.1) lib/better_errors/middleware.rb:57:in `call'
  actionpack (4.2.1) lib/action_dispatch/middleware/debug_exceptions.rb:17:in `call'
  actionpack (4.2.1) lib/action_dispatch/middleware/show_exceptions.rb:30:in `call'
  railties (4.2.1) lib/rails/rack/logger.rb:38:in `call_app'
  railties (4.2.1) lib/rails/rack/logger.rb:20:in `block in call'
  activesupport (4.2.1) lib/active_support/tagged_logging.rb:68:in `block in tagged'
  activesupport (4.2.1) lib/active_support/tagged_logging.rb:26:in `tagged'
  activesupport (4.2.1) lib/active_support/tagged_logging.rb:68:in `tagged'
  railties (4.2.1) lib/rails/rack/logger.rb:20:in `call'
  quiet_assets (1.1.0) lib/quiet_assets.rb:27:in `call_with_quiet_assets'
  actionpack (4.2.1) lib/action_dispatch/middleware/request_id.rb:21:in `call'
  rack (1.6.1) lib/rack/methodoverride.rb:22:in `call'
  rack (1.6.1) lib/rack/runtime.rb:18:in `call'
  activesupport (4.2.1) lib/active_support/cache/strategy/local_cache_middleware.rb:28:in `call'
  rack (1.6.1) lib/rack/lock.rb:17:in `call'
  actionpack (4.2.1) lib/action_dispatch/middleware/static.rb:113:in `call'
  rack (1.6.1) lib/rack/sendfile.rb:113:in `call'
  airbrake (4.1.0) lib/airbrake/user_informer.rb:16:in `_call'
  airbrake (4.1.0) lib/airbrake/user_informer.rb:12:in `call'
  rack-mini-profiler (0.9.3) lib/mini_profiler/profiler.rb:276:in `call'
  railties (4.2.1) lib/rails/engine.rb:518:in `call'
  railties (4.2.1) lib/rails/application.rb:164:in `call'
  rack (1.6.1) lib/rack/lock.rb:17:in `call'
  rack (1.6.1) lib/rack/content_length.rb:15:in `call'
  rack (1.6.1) lib/rack/handler/webrick.rb:89:in `service'
  webrick (1.3.1) lib/webrick/httpserver.rb:138:in `service'
  webrick (1.3.1) lib/webrick/httpserver.rb:94:in `run'
  webrick (1.3.1) lib/webrick/server.rb:191:in `block in start_thread'

any pointers where to start looking?

Hi. Thank you for the issue. For the first line of the backtrace you can see that it may be caused by modular-scale. I'd start with that

Please reopen, the same version of modular-scale is used in 4.0.5 and there it works just fine. I did some more investigation: with 5.0.1 it will work in the development environment but specs will fail with

     ActionView::Template::Error:
       can't modify frozen Array
         (in /Users/bvogel/Development/buddy/app/assets/stylesheets/application.scss.erb)
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/modular-scale-1.0.6/lib/modular-scale.rb:118:in `delete_if'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/modular-scale-1.0.6/lib/modular-scale.rb:118:in `trim_list'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/script/tree/funcall.rb:140:in `_perform'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/script/tree/node.rb:50:in `perform'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:468:in `visit_variable'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/base.rb:36:in `visit'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:158:in `block in visit'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/stack.rb:79:in `block in with_base'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/stack.rb:115:in `with_frame'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/stack.rb:79:in `with_base'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:158:in `visit'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:299:in `block (2 levels) in visit_if'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:299:in `map'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:299:in `block in visit_if'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:179:in `with_environment'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:298:in `visit_if'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/base.rb:36:in `visit'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:158:in `block in visit'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/stack.rb:79:in `block in with_base'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/stack.rb:115:in `with_frame'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/stack.rb:79:in `with_base'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:158:in `visit'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:8:in `visit'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/script/tree/funcall.rb:248:in `block (3 levels) in perform_sass_fn'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/script/tree/funcall.rb:248:in `each'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/script/tree/funcall.rb:248:in `block (2 levels) in perform_sass_fn'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/script/tree/funcall.rb:247:in `catch'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/script/tree/funcall.rb:247:in `block in perform_sass_fn'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:84:in `perform_arguments'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/script/tree/funcall.rb:244:in `perform_sass_fn'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/script/tree/funcall.rb:131:in `_perform'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/script/tree/node.rb:50:in `perform'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:402:in `visit_return'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/base.rb:36:in `visit'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:158:in `block in visit'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/stack.rb:79:in `block in with_base'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/stack.rb:115:in `with_frame'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/stack.rb:79:in `with_base'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:158:in `visit'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:8:in `visit'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/script/tree/funcall.rb:248:in `block (3 levels) in perform_sass_fn'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/script/tree/funcall.rb:248:in `each'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/script/tree/funcall.rb:248:in `block (2 levels) in perform_sass_fn'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/script/tree/funcall.rb:247:in `catch'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/script/tree/funcall.rb:247:in `block in perform_sass_fn'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:84:in `perform_arguments'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/script/tree/funcall.rb:244:in `perform_sass_fn'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/script/tree/funcall.rb:131:in `_perform'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/script/tree/node.rb:50:in `perform'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/script/tree/funcall.rb:170:in `perform_arg'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/script/tree/funcall.rb:124:in `block in _perform'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/script/tree/funcall.rb:124:in `each'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/script/tree/funcall.rb:124:in `each_with_index'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/script/tree/funcall.rb:124:in `each'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/script/tree/funcall.rb:124:in `map'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/script/tree/funcall.rb:124:in `_perform'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/script/tree/node.rb:50:in `perform'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/script/tree/operation.rb:64:in `_perform'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/script/tree/node.rb:50:in `perform'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/script/tree/operation.rb:64:in `_perform'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/script/tree/node.rb:50:in `perform'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:297:in `visit_if'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/base.rb:36:in `visit'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:158:in `block in visit'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/stack.rb:79:in `block in with_base'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/stack.rb:115:in `with_frame'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/stack.rb:79:in `with_base'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:158:in `visit'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:299:in `block (2 levels) in visit_if'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:299:in `map'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:299:in `block in visit_if'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:179:in `with_environment'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:298:in `visit_if'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/base.rb:36:in `visit'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:158:in `block in visit'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/stack.rb:79:in `block in with_base'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/stack.rb:115:in `with_frame'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/stack.rb:79:in `with_base'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:158:in `visit'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:8:in `visit'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/script/tree/funcall.rb:248:in `block (3 levels) in perform_sass_fn'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/script/tree/funcall.rb:248:in `each'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/script/tree/funcall.rb:248:in `block (2 levels) in perform_sass_fn'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/script/tree/funcall.rb:247:in `catch'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/script/tree/funcall.rb:247:in `block in perform_sass_fn'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:84:in `perform_arguments'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/script/tree/funcall.rb:244:in `perform_sass_fn'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/script/tree/funcall.rb:131:in `_perform'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/script/tree/node.rb:50:in `perform'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:402:in `visit_return'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/base.rb:36:in `visit'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:158:in `block in visit'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/stack.rb:79:in `block in with_base'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/stack.rb:115:in `with_frame'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/stack.rb:79:in `with_base'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:158:in `visit'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:8:in `visit'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/script/tree/funcall.rb:248:in `block (3 levels) in perform_sass_fn'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/script/tree/funcall.rb:248:in `each'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/script/tree/funcall.rb:248:in `block (2 levels) in perform_sass_fn'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/script/tree/funcall.rb:247:in `catch'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/script/tree/funcall.rb:247:in `block in perform_sass_fn'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:84:in `perform_arguments'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/script/tree/funcall.rb:244:in `perform_sass_fn'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/script/tree/funcall.rb:131:in `_perform'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/script/tree/node.rb:50:in `perform'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:394:in `visit_prop'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/base.rb:36:in `visit'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:158:in `block in visit'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/stack.rb:79:in `block in with_base'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/stack.rb:115:in `with_frame'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/stack.rb:79:in `with_base'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:158:in `visit'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:430:in `block (2 levels) in visit_rule'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:430:in `map'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:430:in `block in visit_rule'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:179:in `with_environment'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:428:in `visit_rule'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/base.rb:36:in `visit'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:158:in `block in visit'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/stack.rb:79:in `block in with_base'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/stack.rb:115:in `with_frame'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/stack.rb:79:in `with_base'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:158:in `visit'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:325:in `block (2 levels) in visit_import'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:325:in `map'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:325:in `block in visit_import'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/stack.rb:88:in `block in with_import'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/stack.rb:115:in `with_frame'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/stack.rb:88:in `with_import'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:322:in `visit_import'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/base.rb:36:in `visit'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:158:in `block in visit'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/stack.rb:79:in `block in with_base'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/stack.rb:115:in `with_frame'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/stack.rb:79:in `with_base'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:158:in `visit'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:325:in `block (2 levels) in visit_import'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:325:in `map'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:325:in `block in visit_import'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/stack.rb:88:in `block in with_import'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/stack.rb:115:in `with_frame'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/stack.rb:88:in `with_import'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:322:in `visit_import'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/base.rb:36:in `visit'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:158:in `block in visit'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/stack.rb:79:in `block in with_base'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/stack.rb:115:in `with_frame'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/stack.rb:79:in `with_base'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:158:in `visit'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:325:in `block (2 levels) in visit_import'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:325:in `map'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:325:in `block in visit_import'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/stack.rb:88:in `block in with_import'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/stack.rb:115:in `with_frame'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/stack.rb:88:in `with_import'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:322:in `visit_import'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/base.rb:36:in `visit'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:158:in `block in visit'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/stack.rb:79:in `block in with_base'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/stack.rb:115:in `with_frame'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/stack.rb:79:in `with_base'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:158:in `visit'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:325:in `block (2 levels) in visit_import'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:325:in `map'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:325:in `block in visit_import'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/stack.rb:88:in `block in with_import'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/stack.rb:115:in `with_frame'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/stack.rb:88:in `with_import'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:322:in `visit_import'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/base.rb:36:in `visit'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:158:in `block in visit'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/stack.rb:79:in `block in with_base'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/stack.rb:115:in `with_frame'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/stack.rb:79:in `with_base'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:158:in `visit'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/base.rb:52:in `block in visit_children'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/base.rb:52:in `map'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/base.rb:52:in `visit_children'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:167:in `block in visit_children'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:179:in `with_environment'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:166:in `visit_children'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/base.rb:36:in `block in visit'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:186:in `visit_root'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/base.rb:36:in `visit'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:157:in `visit'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/visitors/perform.rb:8:in `visit'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/root_node.rb:36:in `css_tree'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/tree/root_node.rb:20:in `render'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sass-3.4.13/lib/sass/engine.rb:268:in `render'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/compass-rails-2.0.4/lib/compass-rails/patches/sass_importer.rb:48:in `evaluate'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/tilt-1.4.1/lib/tilt/template.rb:103:in `render'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sprockets-2.12.3/lib/sprockets/context.rb:197:in `block in evaluate'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sprockets-2.12.3/lib/sprockets/context.rb:194:in `each'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sprockets-2.12.3/lib/sprockets/context.rb:194:in `evaluate'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sprockets-2.12.3/lib/sprockets/processed_asset.rb:12:in `initialize'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sprockets-2.12.3/lib/sprockets/base.rb:374:in `new'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sprockets-2.12.3/lib/sprockets/base.rb:374:in `block in build_asset'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sprockets-2.12.3/lib/sprockets/base.rb:395:in `circular_call_protection'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sprockets-2.12.3/lib/sprockets/base.rb:373:in `build_asset'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sprockets-2.12.3/lib/sprockets/index.rb:94:in `block in build_asset'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sprockets-2.12.3/lib/sprockets/caching.rb:58:in `cache_asset'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sprockets-2.12.3/lib/sprockets/index.rb:93:in `build_asset'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sprockets-2.12.3/lib/sprockets/base.rb:287:in `find_asset'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sprockets-2.12.3/lib/sprockets/index.rb:61:in `find_asset'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sprockets-2.12.3/lib/sprockets/bundled_asset.rb:37:in `init_with'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sprockets-2.12.3/lib/sprockets/asset.rb:24:in `from_hash'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sprockets-2.12.3/lib/sprockets/caching.rb:54:in `cache_asset'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sprockets-2.12.3/lib/sprockets/index.rb:93:in `build_asset'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sprockets-2.12.3/lib/sprockets/base.rb:287:in `find_asset'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sprockets-2.12.3/lib/sprockets/index.rb:61:in `find_asset'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sprockets-2.12.3/lib/sprockets/base.rb:295:in `[]'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sprockets-rails-2.3.0/lib/sprockets/rails/helper.rb:132:in `asset_digest_path'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sprockets-rails-2.3.0/lib/sprockets/rails/helper.rb:85:in `compute_asset_path'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionview-4.2.1/lib/action_view/helpers/asset_url_helper.rb:135:in `asset_path'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sprockets-rails-2.3.0/lib/sprockets/rails/helper.rb:100:in `asset_path'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionview-4.2.1/lib/action_view/helpers/asset_url_helper.rb:267:in `stylesheet_path'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionview-4.2.1/lib/action_view/helpers/asset_tag_helper.rb:100:in `block in stylesheet_link_tag'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionview-4.2.1/lib/action_view/helpers/asset_tag_helper.rb:96:in `map'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionview-4.2.1/lib/action_view/helpers/asset_tag_helper.rb:96:in `stylesheet_link_tag'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/sprockets-rails-2.3.0/lib/sprockets/rails/helper.rb:183:in `stylesheet_link_tag'
     # ./app/views/layouts/login.html.haml:6:in `_app_views_layouts_login_html_haml__40792529938104361_70356704034000'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionview-4.2.1/lib/action_view/template.rb:145:in `block in render'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/activesupport-4.2.1/lib/active_support/notifications.rb:166:in `instrument'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionview-4.2.1/lib/action_view/template.rb:333:in `instrument'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionview-4.2.1/lib/action_view/template.rb:143:in `render'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionview-4.2.1/lib/action_view/renderer/template_renderer.rb:66:in `render_with_layout'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionview-4.2.1/lib/action_view/renderer/template_renderer.rb:52:in `render_template'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionview-4.2.1/lib/action_view/renderer/template_renderer.rb:14:in `render'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionview-4.2.1/lib/action_view/renderer/renderer.rb:42:in `render_template'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionview-4.2.1/lib/action_view/renderer/renderer.rb:23:in `render'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionview-4.2.1/lib/action_view/rendering.rb:100:in `_render_template'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionpack-4.2.1/lib/action_controller/metal/streaming.rb:217:in `_render_template'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionview-4.2.1/lib/action_view/rendering.rb:83:in `render_to_body'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionpack-4.2.1/lib/action_controller/metal/rendering.rb:32:in `render_to_body'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionpack-4.2.1/lib/action_controller/metal/renderers.rb:37:in `render_to_body'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionpack-4.2.1/lib/abstract_controller/rendering.rb:25:in `render'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionpack-4.2.1/lib/action_controller/metal/rendering.rb:16:in `render'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionpack-4.2.1/lib/action_controller/metal/instrumentation.rb:44:in `block (2 levels) in render'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/activesupport-4.2.1/lib/active_support/core_ext/benchmark.rb:12:in `block in ms'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/activesupport-4.2.1/lib/active_support/core_ext/benchmark.rb:12:in `ms'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionpack-4.2.1/lib/action_controller/metal/instrumentation.rb:44:in `block in render'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionpack-4.2.1/lib/action_controller/metal/instrumentation.rb:87:in `cleanup_view_runtime'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/activerecord-4.2.1/lib/active_record/railties/controller_runtime.rb:25:in `cleanup_view_runtime'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionpack-4.2.1/lib/action_controller/metal/instrumentation.rb:43:in `render'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/remotipart-1.2.1/lib/remotipart/render_overrides.rb:14:in `render_with_remotipart'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionpack-4.2.1/lib/action_controller/metal/implicit_render.rb:10:in `default_render'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionpack-4.2.1/lib/action_controller/metal/implicit_render.rb:5:in `send_action'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionpack-4.2.1/lib/abstract_controller/base.rb:198:in `process_action'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionpack-4.2.1/lib/action_controller/metal/rendering.rb:10:in `process_action'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionpack-4.2.1/lib/abstract_controller/callbacks.rb:20:in `block in process_action'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/activesupport-4.2.1/lib/active_support/callbacks.rb:117:in `call'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/activesupport-4.2.1/lib/active_support/callbacks.rb:117:in `call'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/activesupport-4.2.1/lib/active_support/callbacks.rb:555:in `block (2 levels) in compile'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/activesupport-4.2.1/lib/active_support/callbacks.rb:505:in `call'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/activesupport-4.2.1/lib/active_support/callbacks.rb:505:in `call'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/activesupport-4.2.1/lib/active_support/callbacks.rb:92:in `_run_callbacks'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/activesupport-4.2.1/lib/active_support/callbacks.rb:776:in `_run_process_action_callbacks'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/activesupport-4.2.1/lib/active_support/callbacks.rb:81:in `run_callbacks'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionpack-4.2.1/lib/abstract_controller/callbacks.rb:19:in `process_action'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionpack-4.2.1/lib/action_controller/metal/rescue.rb:29:in `process_action'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionpack-4.2.1/lib/action_controller/metal/instrumentation.rb:32:in `block in process_action'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/activesupport-4.2.1/lib/active_support/notifications.rb:164:in `block in instrument'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/activesupport-4.2.1/lib/active_support/notifications/instrumenter.rb:20:in `instrument'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/activesupport-4.2.1/lib/active_support/notifications.rb:164:in `instrument'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionpack-4.2.1/lib/action_controller/metal/instrumentation.rb:30:in `process_action'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionpack-4.2.1/lib/action_controller/metal/params_wrapper.rb:250:in `process_action'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/activerecord-4.2.1/lib/active_record/railties/controller_runtime.rb:18:in `process_action'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionpack-4.2.1/lib/abstract_controller/base.rb:137:in `process'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionview-4.2.1/lib/action_view/rendering.rb:30:in `process'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionpack-4.2.1/lib/action_controller/metal.rb:196:in `dispatch'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionpack-4.2.1/lib/action_controller/metal/rack_delegation.rb:13:in `dispatch'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionpack-4.2.1/lib/action_controller/metal.rb:237:in `block in action'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionpack-4.2.1/lib/action_dispatch/routing/route_set.rb:74:in `call'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionpack-4.2.1/lib/action_dispatch/routing/route_set.rb:74:in `dispatch'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionpack-4.2.1/lib/action_dispatch/routing/route_set.rb:43:in `serve'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionpack-4.2.1/lib/action_dispatch/journey/router.rb:43:in `block in serve'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionpack-4.2.1/lib/action_dispatch/journey/router.rb:30:in `each'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionpack-4.2.1/lib/action_dispatch/journey/router.rb:30:in `serve'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionpack-4.2.1/lib/action_dispatch/routing/route_set.rb:819:in `call'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/rack-1.6.1/lib/rack/etag.rb:24:in `call'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/rack-1.6.1/lib/rack/conditionalget.rb:25:in `call'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/rack-1.6.1/lib/rack/head.rb:13:in `call'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/remotipart-1.2.1/lib/remotipart/middleware.rb:27:in `call'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionpack-4.2.1/lib/action_dispatch/middleware/params_parser.rb:27:in `call'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionpack-4.2.1/lib/action_dispatch/middleware/flash.rb:260:in `call'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/rack-1.6.1/lib/rack/session/abstract/id.rb:225:in `context'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/rack-1.6.1/lib/rack/session/abstract/id.rb:220:in `call'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionpack-4.2.1/lib/action_dispatch/middleware/cookies.rb:560:in `call'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/activerecord-4.2.1/lib/active_record/query_cache.rb:36:in `call'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/activerecord-4.2.1/lib/active_record/connection_adapters/abstract/connection_pool.rb:649:in `call'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionpack-4.2.1/lib/action_dispatch/middleware/callbacks.rb:29:in `block in call'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/activesupport-4.2.1/lib/active_support/callbacks.rb:88:in `call'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/activesupport-4.2.1/lib/active_support/callbacks.rb:88:in `_run_callbacks'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/activesupport-4.2.1/lib/active_support/callbacks.rb:776:in `_run_call_callbacks'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/activesupport-4.2.1/lib/active_support/callbacks.rb:81:in `run_callbacks'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionpack-4.2.1/lib/action_dispatch/middleware/callbacks.rb:27:in `call'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionpack-4.2.1/lib/action_dispatch/middleware/remote_ip.rb:78:in `call'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/airbrake-4.1.0/lib/airbrake/rails/middleware.rb:13:in `call'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionpack-4.2.1/lib/action_dispatch/middleware/debug_exceptions.rb:17:in `call'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionpack-4.2.1/lib/action_dispatch/middleware/show_exceptions.rb:30:in `call'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/railties-4.2.1/lib/rails/rack/logger.rb:38:in `call_app'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/railties-4.2.1/lib/rails/rack/logger.rb:20:in `block in call'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/activesupport-4.2.1/lib/active_support/tagged_logging.rb:68:in `block in tagged'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/activesupport-4.2.1/lib/active_support/tagged_logging.rb:26:in `tagged'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/activesupport-4.2.1/lib/active_support/tagged_logging.rb:68:in `tagged'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/railties-4.2.1/lib/rails/rack/logger.rb:20:in `call'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionpack-4.2.1/lib/action_dispatch/middleware/request_id.rb:21:in `call'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/rack-1.6.1/lib/rack/methodoverride.rb:22:in `call'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/rack-1.6.1/lib/rack/runtime.rb:18:in `call'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/activesupport-4.2.1/lib/active_support/cache/strategy/local_cache_middleware.rb:28:in `call'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/rack-1.6.1/lib/rack/lock.rb:17:in `call'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/actionpack-4.2.1/lib/action_dispatch/middleware/static.rb:113:in `call'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/rack-1.6.1/lib/rack/sendfile.rb:113:in `call'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/airbrake-4.1.0/lib/airbrake/user_informer.rb:16:in `_call'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/airbrake-4.1.0/lib/airbrake/user_informer.rb:12:in `call'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/railties-4.2.1/lib/rails/engine.rb:518:in `call'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/railties-4.2.1/lib/rails/application.rb:164:in `call'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/rack-1.6.1/lib/rack/urlmap.rb:66:in `block in call'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/rack-1.6.1/lib/rack/urlmap.rb:50:in `each'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/rack-1.6.1/lib/rack/urlmap.rb:50:in `call'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/capybara-2.4.4/lib/capybara/server.rb:19:in `call'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/rack-1.6.1/lib/rack/handler/webrick.rb:89:in `service'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/webrick-1.3.1/lib/webrick/httpserver.rb:138:in `service'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/webrick-1.3.1/lib/webrick/httpserver.rb:94:in `run'
     # /Users/bvogel/.rvm/gems/ruby-2.2.1/gems/webrick-1.3.1/lib/webrick/server.rb:191:in `block in start_thread'

To resume: same codebase works with 4.0.5 in dev and test; works in dev, fails in test with 5.0.1; fails in dev and test with 5.0.2/3 - so I'm blaming sass-rails as that's my only variable.

(I'm aware that nowhere in the stack sass-rails is mentioned, but as pointed out above, it's the only variable, I suspected sprocket 3.1, but its 2.12.3 in all cases)

We released sass-rails 5.0 because some plugins may not work with the new API that we released. I don't know if this is the case but maybe modular-scale need to change their code to work with sass-rails 5. Given you are using a version of August 2013, this may be the case.