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Uglifier::Error: Unexpected token: punc ((). To use ES6 syntax, harmony mode must be enabled with Uglifier.new(:harmony => true)

See original GitHub issue

Hi, When I run “rake assets:precompile RAILS_ENV=production” command, I have issue. rake assets:precompile RAILS_ENV=production rake aborted! Uglifier::Error: Unexpected token: punc ((). To use ES6 syntax, harmony mode must be enabled with Uglifier.new(:harmony => true). /Users/leonverspeek/.rvm/gems/ruby-2.3.1@zombie/gems/uglifier-4.0.2/lib/uglifier.rb:237:in parse_result' /Users/leonverspeek/.rvm/gems/ruby-2.3.1@zombie/gems/uglifier-4.0.2/lib/uglifier.rb:219:in run_uglifyjs’ /Users/leonverspeek/.rvm/gems/ruby-2.3.1@zombie/gems/uglifier-4.0.2/lib/uglifier.rb:169:in compile' /Users/leonverspeek/.rvm/gems/ruby-2.3.1@zombie/gems/sprockets-3.7.1/lib/sprockets/uglifier_compressor.rb:53:in call’ /Users/leonverspeek/.rvm/gems/ruby-2.3.1@zombie/gems/sprockets-3.7.1/lib/sprockets/uglifier_compressor.rb:28:in call' /Users/leonverspeek/.rvm/gems/ruby-2.3.1@zombie/gems/sprockets-3.7.1/lib/sprockets/processor_utils.rb:75:in call_processor’ /Users/leonverspeek/.rvm/gems/ruby-2.3.1@zombie/gems/sprockets-3.7.1/lib/sprockets/processor_utils.rb:57:in block in call_processors' /Users/leonverspeek/.rvm/gems/ruby-2.3.1@zombie/gems/sprockets-3.7.1/lib/sprockets/processor_utils.rb:56:in reverse_each’ /Users/leonverspeek/.rvm/gems/ruby-2.3.1@zombie/gems/sprockets-3.7.1/lib/sprockets/processor_utils.rb:56:in call_processors' /Users/leonverspeek/.rvm/gems/ruby-2.3.1@zombie/gems/sprockets-3.7.1/lib/sprockets/loader.rb:134:in load_from_unloaded’ /Users/leonverspeek/.rvm/gems/ruby-2.3.1@zombie/gems/sprockets-3.7.1/lib/sprockets/loader.rb:60:in block in load' /Users/leonverspeek/.rvm/gems/ruby-2.3.1@zombie/gems/sprockets-3.7.1/lib/sprockets/loader.rb:317:in fetch_asset_from_dependency_cache’ /Users/leonverspeek/.rvm/gems/ruby-2.3.1@zombie/gems/sprockets-3.7.1/lib/sprockets/loader.rb:44:in load' /Users/leonverspeek/.rvm/gems/ruby-2.3.1@zombie/gems/sprockets-3.7.1/lib/sprockets/cached_environment.rb:20:in block in initialize’ /Users/leonverspeek/.rvm/gems/ruby-2.3.1@zombie/gems/sprockets-3.7.1/lib/sprockets/cached_environment.rb:47:in load' /Users/leonverspeek/.rvm/gems/ruby-2.3.1@zombie/gems/sprockets-3.7.1/lib/sprockets/base.rb:66:in find_asset’ /Users/leonverspeek/.rvm/gems/ruby-2.3.1@zombie/gems/sprockets-3.7.1/lib/sprockets/base.rb:73:in find_all_linked_assets' /Users/leonverspeek/.rvm/gems/ruby-2.3.1@zombie/gems/sprockets-3.7.1/lib/sprockets/manifest.rb:142:in block in find’ /Users/leonverspeek/.rvm/gems/ruby-2.3.1@zombie/gems/sprockets-3.7.1/lib/sprockets/legacy.rb:114:in block (2 levels) in logical_paths' /Users/leonverspeek/.rvm/gems/ruby-2.3.1@zombie/gems/sprockets-3.7.1/lib/sprockets/path_utils.rb:228:in block in stat_tree’ /Users/leonverspeek/.rvm/gems/ruby-2.3.1@zombie/gems/sprockets-3.7.1/lib/sprockets/path_utils.rb:212:in block in stat_directory' /Users/leonverspeek/.rvm/gems/ruby-2.3.1@zombie/gems/sprockets-3.7.1/lib/sprockets/path_utils.rb:209:in each’ /Users/leonverspeek/.rvm/gems/ruby-2.3.1@zombie/gems/sprockets-3.7.1/lib/sprockets/path_utils.rb:209:in stat_directory' /Users/leonverspeek/.rvm/gems/ruby-2.3.1@zombie/gems/sprockets-3.7.1/lib/sprockets/path_utils.rb:227:in stat_tree’ /Users/leonverspeek/.rvm/gems/ruby-2.3.1@zombie/gems/sprockets-3.7.1/lib/sprockets/legacy.rb:105:in each' /Users/leonverspeek/.rvm/gems/ruby-2.3.1@zombie/gems/sprockets-3.7.1/lib/sprockets/legacy.rb:105:in block in logical_paths’ /Users/leonverspeek/.rvm/gems/ruby-2.3.1@zombie/gems/sprockets-3.7.1/lib/sprockets/legacy.rb:104:in each' /Users/leonverspeek/.rvm/gems/ruby-2.3.1@zombie/gems/sprockets-3.7.1/lib/sprockets/legacy.rb:104:in logical_paths’ /Users/leonverspeek/.rvm/gems/ruby-2.3.1@zombie/gems/sprockets-3.7.1/lib/sprockets/manifest.rb:140:in find' /Users/leonverspeek/.rvm/gems/ruby-2.3.1@zombie/gems/sprockets-3.7.1/lib/sprockets/manifest.rb:185:in compile’ /Users/leonverspeek/.rvm/gems/ruby-2.3.1@zombie/gems/sprockets-rails-3.2.1/lib/sprockets/rails/task.rb:68:in block (3 levels) in define' /Users/leonverspeek/.rvm/gems/ruby-2.3.1@zombie/gems/sprockets-3.7.1/lib/rake/sprocketstask.rb:147:in with_logger’ /Users/leonverspeek/.rvm/gems/ruby-2.3.1@zombie/gems/sprockets-rails-3.2.1/lib/sprockets/rails/task.rb:67:in block (2 levels) in define' /Users/leonverspeek/.rvm/gems/ruby-2.3.1@zombie/gems/rake-12.2.1/exe/rake:27:in <top (required)>’ /Users/leonverspeek/.rvm/gems/ruby-2.3.1@zombie/bin/ruby_executable_hooks:15:in eval' /Users/leonverspeek/.rvm/gems/ruby-2.3.1@zombie/bin/ruby_executable_hooks:15:in <main>’ Tasks: TOP => assets:precompile (See full trace by running task with --trace)

How to fix this issue?

Issue Analytics

State:
Created 6 years ago
Reactions:41
Comments:31 (1 by maintainers)

Top GitHub Comments

1277reactions

abrahamcommented, Dec 17, 2017

Try replacing

config.assets.js_compressor = :uglifier

with

config.assets.js_compressor = Uglifier.new(harmony: true)

in config/environments/production.rb

77reactions

chengs2416mecommented, Jan 4, 2018

abraham, you save my day

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