Debugging Compilation Errors (Psych)

I’m getting an ambiguous error when running “foreman start -f Procfile.static”. The most interpretable part of the trace points to Psych, so I assume there’s a .yml config file that’s upset. Is there a way to see which file is failing?

Here’s the trace:
19:04:27 rails.1 | /home/tribe/.rvm/rubies/ruby-2.6.5/lib/ruby/2.6.0/psych.rb:456:in parse': (<unknown>): found character that cannot start any token while scanning for the next token at line 13 column 1 (Psych::SyntaxError) 19:04:27 rails.1 | from /home/tribe/.rvm/rubies/ruby-2.6.5/lib/ruby/2.6.0/psych.rb:456:in parse_stream’
19:04:27 rails.1 | from /home/tribe/.rvm/rubies/ruby-2.6.5/lib/ruby/2.6.0/psych.rb:390:in parse' 19:04:27 rails.1 | from /home/tribe/.rvm/rubies/ruby-2.6.5/lib/ruby/2.6.0/psych.rb:277:in load’
19:04:27 rails.1 | from /home/tribe/.rvm/gems/ruby-2.6.5/gems/bootsnap-1.4.3/lib/bootsnap/compile_cache/yaml.rb:12:in input_to_storage' 19:04:27 rails.1 | from /home/tribe/.rvm/gems/ruby-2.6.5/gems/bootsnap-1.4.3/lib/bootsnap/compile_cache/yaml.rb:50:in fetch’
19:04:27 rails.1 | from /home/tribe/.rvm/gems/ruby-2.6.5/gems/bootsnap-1.4.3/lib/bootsnap/compile_cache/yaml.rb:50:in block in install!' 19:04:27 rails.1 | from /home/tribe/sharetribe/config/config_loader.rb:31:in read_yaml_file’
19:04:27 rails.1 | from /home/tribe/sharetribe/config/config_loader.rb:18:in load_app_config' 19:04:27 rails.1 | from /home/tribe/sharetribe/config/application.rb:92:in class:Application
19:04:27 rails.1 | from /home/tribe/sharetribe/config/application.rb:33:in <module:Kassi>' 19:04:27 rails.1 | from /home/tribe/sharetribe/config/application.rb:32:in
19:04:27 rails.1 | from /home/tribe/.rvm/gems/ruby-2.6.5/gems/bootsnap-1.4.3/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:22:in require' 19:04:27 rails.1 | from /home/tribe/.rvm/gems/ruby-2.6.5/gems/bootsnap-1.4.3/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:22:in block in require_with_bootsnap_lfi’
19:04:27 rails.1 | from /home/tribe/.rvm/gems/ruby-2.6.5/gems/bootsnap-1.4.3/lib/bootsnap/load_path_cache/loaded_features_index.rb:92:in register' 19:04:27 rails.1 | from /home/tribe/.rvm/gems/ruby-2.6.5/gems/bootsnap-1.4.3/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:21:in require_with_bootsnap_lfi’
19:04:27 rails.1 | from /home/tribe/.rvm/gems/ruby-2.6.5/gems/bootsnap-1.4.3/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:30:in require' 19:04:27 rails.1 | from /home/tribe/.rvm/gems/ruby-2.6.5/gems/activesupport-5.2.3/lib/active_support/dependencies.rb:291:in block in require’
19:04:27 rails.1 | from /home/tribe/.rvm/gems/ruby-2.6.5/gems/activesupport-5.2.3/lib/active_support/dependencies.rb:257:in load_dependency' 19:04:27 rails.1 | from /home/tribe/.rvm/gems/ruby-2.6.5/gems/activesupport-5.2.3/lib/active_support/dependencies.rb:291:in require’
19:04:27 rails.1 | from /home/tribe/.rvm/gems/ruby-2.6.5/gems/railties-5.2.3/lib/rails/commands/server/server_command.rb:145:in block in perform' 19:04:27 rails.1 | from /home/tribe/.rvm/gems/ruby-2.6.5/gems/railties-5.2.3/lib/rails/commands/server/server_command.rb:142:in tap’
19:04:27 rails.1 | from /home/tribe/.rvm/gems/ruby-2.6.5/gems/railties-5.2.3/lib/rails/commands/server/server_command.rb:142:in perform' 19:04:27 rails.1 | from /home/tribe/.rvm/gems/ruby-2.6.5/gems/thor-0.20.3/lib/thor/command.rb:27:in run’
19:04:27 rails.1 | from /home/tribe/.rvm/gems/ruby-2.6.5/gems/thor-0.20.3/lib/thor/invocation.rb:126:in invoke_command' 19:04:27 rails.1 | from /home/tribe/.rvm/gems/ruby-2.6.5/gems/thor-0.20.3/lib/thor.rb:387:in dispatch’
19:04:27 rails.1 | from /home/tribe/.rvm/gems/ruby-2.6.5/gems/railties-5.2.3/lib/rails/command/base.rb:65:in perform' 19:04:27 rails.1 | from /home/tribe/.rvm/gems/ruby-2.6.5/gems/railties-5.2.3/lib/rails/command.rb:46:in invoke’
19:04:27 rails.1 | from /home/tribe/.rvm/gems/ruby-2.6.5/gems/railties-5.2.3/lib/rails/commands.rb:18:in <main>' 19:04:27 rails.1 | from /home/tribe/.rvm/gems/ruby-2.6.5/gems/bootsnap-1.4.3/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:22:in require’
19:04:27 rails.1 | from /home/tribe/.rvm/gems/ruby-2.6.5/gems/bootsnap-1.4.3/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:22:in block in require_with_bootsnap_lfi' 19:04:27 rails.1 | from /home/tribe/.rvm/gems/ruby-2.6.5/gems/bootsnap-1.4.3/lib/bootsnap/load_path_cache/loaded_features_index.rb:92:in register’
19:04:27 rails.1 | from /home/tribe/.rvm/gems/ruby-2.6.5/gems/bootsnap-1.4.3/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:21:in require_with_bootsnap_lfi' 19:04:27 rails.1 | from /home/tribe/.rvm/gems/ruby-2.6.5/gems/bootsnap-1.4.3/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:30:in require’
19:04:27 rails.1 | from /home/tribe/.rvm/gems/ruby-2.6.5/gems/activesupport-5.2.3/lib/active_support/dependencies.rb:291:in block in require' 19:04:27 rails.1 | from /home/tribe/.rvm/gems/ruby-2.6.5/gems/activesupport-5.2.3/lib/active_support/dependencies.rb:257:in load_dependency’
19:04:27 rails.1 | from /home/tribe/.rvm/gems/ruby-2.6.5/gems/activesupport-5.2.3/lib/active_support/dependencies.rb:291:in require' 19:04:27 rails.1 | from bin/rails:4:in
19:04:28 rails.1 | exited with code 1
19:04:28 system | sending SIGTERM to all processes
19:04:28 rails-server-assets.1 | terminated by SIGTERM

The syntax error, as is to be expected, was extremely simple: a tab character hidden in config.yml.

Still, if there’s a way to pinpoint these kinds of errors in the future, I’d like to know.