Rails 5 Heroku部署错误：ExecJS :: ProgramError：SyntaxError：意外的标记：名称（autoRegisterNamespace）

Question

尝试将Rails 5应用程序部署到Heroku时，当它执行运行：rake assets:precompile时，我收到以下错误：

remote:        ExecJS::ProgramError: SyntaxError: Unexpected token: name (autoRegisterNamespace) (line: 14767, col: 7, pos: 457487)
remote:        Error
remote:        at new JS_Parse_Error (<eval>:3623:11948)
remote:        at js_error (<eval>:3623:12167)
remote:        at croak (<eval>:3623:21858)
remote:        at token_error (<eval>:3623:21995)
remote:        at unexpected (<eval>:3623:22083)
remote:        at semicolon (<eval>:3623:22601)
remote:        at simple_statement (<eval>:3623:25779)
remote:        at <eval>:3623:23567
remote:        at <eval>:3623:22774
remote:        at block_ (<eval>:3623:27903)
remote:        at <eval>:3623:23677
remote:        at <eval>:3623:22774
remote:        new JS_Parse_Error ((execjs):3623:11948)
remote:        js_error ((execjs):3623:12167)
remote:        croak ((execjs):3623:21858)
remote:        token_error ((execjs):3623:21995)
remote:        unexpected ((execjs):3623:22083)
remote:        semicolon ((execjs):3623:22601)
remote:        simple_statement ((execjs):3623:25779)
remote:        (execjs):3623:23567
remote:        (execjs):3623:22774
remote:        block_ ((execjs):3623:27903)
remote:        (execjs):3623:23677
remote:        (execjs):3623:22774
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/execjs-2.7.0/lib/execjs/ruby_racer_runtime.rb:47:in `rescue in block in call'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/execjs-2.7.0/lib/execjs/ruby_racer_runtime.rb:44:in `block in call'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/execjs-2.7.0/lib/execjs/ruby_racer_runtime.rb:75:in `block in lock'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/execjs-2.7.0/lib/execjs/ruby_racer_runtime.rb:73:in `call'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/execjs-2.7.0/lib/execjs/ruby_racer_runtime.rb:73:in `Locker'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/execjs-2.7.0/lib/execjs/ruby_racer_runtime.rb:73:in `lock'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/execjs-2.7.0/lib/execjs/ruby_racer_runtime.rb:43:in `call'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/uglifier-3.0.1/lib/uglifier.rb:179:in `run_uglifyjs'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/uglifier-3.0.1/lib/uglifier.rb:141:in `compile'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/uglifier_compressor.rb:52:in `call'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/uglifier_compressor.rb:28:in `call'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/processor_utils.rb:75:in `call_processor'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/processor_utils.rb:57:in `block in call_processors'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/processor_utils.rb:56:in `reverse_each'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/processor_utils.rb:56:in `call_processors'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/loader.rb:134:in `load_from_unloaded'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/loader.rb:60:in `block in load'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/loader.rb:317:in `fetch_asset_from_dependency_cache'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/loader.rb:44:in `load'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/cached_environment.rb:20:in `block in initialize'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/cached_environment.rb:47:in `yield'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/cached_environment.rb:47:in `load'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/base.rb:66:in `find_asset'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/base.rb:73:in `find_all_linked_assets'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/manifest.rb:142:in `block in find'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/legacy.rb:114:in `block (2 levels) in logical_paths'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/path_utils.rb:228:in `block in stat_tree'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/path_utils.rb:212:in `block in stat_directory'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/path_utils.rb:209:in `each'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/path_utils.rb:209:in `stat_directory'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/path_utils.rb:227:in `stat_tree'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/legacy.rb:105:in `each'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/legacy.rb:105:in `block in logical_paths'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/legacy.rb:104:in `each'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/legacy.rb:104:in `logical_paths'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/manifest.rb:140:in `find'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/manifest.rb:185:in `compile'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-rails-3.1.1/lib/sprockets/rails/task.rb:68:in `block (3 levels) in define'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/rake/sprocketstask.rb:147:in `with_logger'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-rails-3.1.1/lib/sprockets/rails/task.rb:67:in `block (2 levels) in define'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/rake-11.2.2/exe/rake:27:in `<top (required)>'
remote:        V8::Error: SyntaxError: Unexpected token: name (autoRegisterNamespace)
remote:        at js_error (<eval>:3623:12167)
remote:        at croak (<eval>:3623:21858)
remote:        at token_error (<eval>:3623:21995)
remote:        at unexpected (<eval>:3623:22083)
remote:        at semicolon (<eval>:3623:22601)
remote:        at simple_statement (<eval>:3623:25779)
remote:        at <eval>:3623:23567
remote:        at <eval>:3623:22774
remote:        at block_ (<eval>:3623:27903)
remote:        at <eval>:3623:23677
remote:        at <eval>:3623:22774
remote:        at if_ (<eval>:3623:27671)
remote:        at <eval>:3623:24326
remote:        at <eval>:3623:22774
remote:        at block_ (<eval>:3623:27903)
remote:        at ctor.body (<eval>:3623:27506)
remote:        at function_ (<eval>:3623:27602)
remote:        at expr_atom (<eval>:3623:30888)
remote:        at maybe_unary (<eval>:3624:1562)
remote:        at expr_ops (<eval>:3624:2333)
remote:        at maybe_conditional (<eval>:3624:2425)
remote:        at maybe_assign (<eval>:3624:2868)
remote:        at expression (<eval>:3624:3194)
remote:        at expr_atom (<eval>:3623:30640)
remote:        at maybe_unary (<eval>:3624:1562)
remote:        at expr_ops (<eval>:3624:2333)
remote:        at maybe_conditional (<eval>:3624:2425)
remote:        at maybe_assign (<eval>:3624:2868)
remote:        at expression (<eval>:3624:3194)
remote:        at simple_statement (<eval>:3623:25762)
remote:        at <eval>:3623:23722
remote:        at <eval>:3623:22774
remote:        at block_ (<eval>:3623:27903)
remote:        at ctor.body (<eval>:3623:27506)
remote:        at function_ (<eval>:3623:27602)
remote:        at expr_atom (<eval>:3623:30888)
remote:        at maybe_unary (<eval>:3624:1562)
remote:        at expr_ops (<eval>:3624:2333)
remote:        at maybe_conditional (<eval>:3624:2425)
remote:        at maybe_assign (<eval>:3624:2868)
remote:        at expression (<eval>:3624:3194)
remote:        at expr_list (<eval>:3623:31368)
remote:        at subscripts (<eval>:3624:1271)
remote:        at expr_atom (<eval>:3623:30952)
remote:        at maybe_unary (<eval>:3624:1562)
remote:        at expr_ops (<eval>:3624:2333)
remote:        at maybe_conditional (<eval>:3624:2425)
remote:        at maybe_assign (<eval>:3624:2868)
remote:        at expression (<eval>:3624:3194)
remote:        at expr_atom (<eval>:3623:30640)
remote:        at maybe_unary (<eval>:3624:1562)
remote:        at expr_ops (<eval>:3624:2333)
remote:        at maybe_conditional (<eval>:3624:2425)
remote:        at maybe_assign (<eval>:3624:2868)
remote:        at expression (<eval>:3624:3194)
remote:        at simple_statement (<eval>:3623:25762)
remote:        at <eval>:3623:23722
remote:        at <eval>:3623:22774
remote:        at <eval>:3624:3569
remote:        at parse (<eval>:3624:3809)
remote:        at parse (<eval>:3958:22)
remote:        at uglifier (<eval>:4001:13)
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/execjs-2.7.0/lib/execjs/ruby_racer_runtime.rb:45:in `block in call'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/execjs-2.7.0/lib/execjs/ruby_racer_runtime.rb:75:in `block in lock'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/execjs-2.7.0/lib/execjs/ruby_racer_runtime.rb:73:in `call'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/execjs-2.7.0/lib/execjs/ruby_racer_runtime.rb:73:in `Locker'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/execjs-2.7.0/lib/execjs/ruby_racer_runtime.rb:73:in `lock'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/execjs-2.7.0/lib/execjs/ruby_racer_runtime.rb:43:in `call'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/uglifier-3.0.1/lib/uglifier.rb:179:in `run_uglifyjs'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/uglifier-3.0.1/lib/uglifier.rb:141:in `compile'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/uglifier_compressor.rb:52:in `call'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/uglifier_compressor.rb:28:in `call'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/processor_utils.rb:75:in `call_processor'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/processor_utils.rb:57:in `block in call_processors'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/processor_utils.rb:56:in `reverse_each'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/processor_utils.rb:56:in `call_processors'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/loader.rb:134:in `load_from_unloaded'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/loader.rb:60:in `block in load'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/loader.rb:317:in `fetch_asset_from_dependency_cache'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/loader.rb:44:in `load'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/cached_environment.rb:20:in `block in initialize'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/cached_environment.rb:47:in `yield'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/cached_environment.rb:47:in `load'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/base.rb:66:in `find_asset'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/base.rb:73:in `find_all_linked_assets'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/manifest.rb:142:in `block in find'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/legacy.rb:114:in `block (2 levels) in logical_paths'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/path_utils.rb:228:in `block in stat_tree'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/path_utils.rb:212:in `block in stat_directory'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/path_utils.rb:209:in `each'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/path_utils.rb:209:in `stat_directory'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/path_utils.rb:227:in `stat_tree'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/legacy.rb:105:in `each'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/legacy.rb:105:in `block in logical_paths'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/legacy.rb:104:in `each'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/legacy.rb:104:in `logical_paths'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/manifest.rb:140:in `find'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/sprockets/manifest.rb:185:in `compile'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-rails-3.1.1/lib/sprockets/rails/task.rb:68:in `block (3 levels) in define'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-3.7.0/lib/rake/sprocketstask.rb:147:in `with_logger'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/sprockets-rails-3.1.1/lib/sprockets/rails/task.rb:67:in `block (2 levels) in define'
remote:        /tmp/build_371be96e0ec063bb6c90d7770da64944/vendor/bundle/ruby/2.2.0/gems/rake-11.2.2/exe/rake:27:in `<top (required)>'
remote:        Tasks: TOP => assets:precompile
remote:        (See full trace by running task with --trace)

我的 Gemfile 文件如下：

source 'https://rubygems.org'

gem 'rails', '~> 5.0.0'
gem 'pg'
gem 'puma', '~> 3.0'
gem 'httparty', '~> 0.14.0'

gem 'sass-rails', '~> 5.0'
gem 'uglifier', '>= 1.3.0'
gem 'coffee-rails', '~> 4.2'
gem 'jquery-rails', '~> 4.1', '>= 4.1.1'
gem 'haml-rails', '~> 0.9.0'
gem 'bootstrap-sass', '~> 3.3', '>= 3.3.7'
gem 'owlcarousel-rails', '~> 1.1', '>= 1.1.3.3'
gem 'font-awesome-rails', '~> 4.6', '>= 4.6.3.1'


gem 'turbolinks', '~> 5'
gem 'jbuilder', '~> 2.5'
# Use Redis adapter to run Action Cable in production
# gem 'redis', '~> 3.0'

gem 'therubyracer'
gem 'execjs'

group :development, :test do
  gem 'byebug', platform: :mri
end

group :development do
  gem 'web-console'
  gem 'listen', '~> 3.0.5'
  gem 'spring'
  gem 'spring-watcher-listen', '~> 2.0.0'
end

gem 'tzinfo-data', platforms: [:mingw, :mswin, :x64_mingw, :jruby]

我尝试了带和不带:

gem 'therubyracer'
gem 'execjs'

没什么作用。在我的Mac本地运行rake assets:precompile是有效的...

- Niels Kristian

---

你在JavaScript中使用了ES6语法，可能在Heroku上不被支持，请检查。 - Santosh Sharma

Answer 1

可能与javascript/coffescript语法有关。检查一下是否使用了let，应该用var替换它。

编辑 - 参见@Guilherme Lages Santos的回答。自版本3.2.0以来，Uglifier已经添加了ES6支持，因此您可以在环境文件中像这样使用它。

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

- Florin Ionce

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在Rails 5中，我通过将文件从.js重命名为.js.es6来解决了问题。奇怪的是，我的staging部署可以工作，但我的production部署却不能。 - Marcelo

请参考Guilherme Lages Santos的回答 - Uglifier从3.2.0版本开始支持ES6语法。 - randallreedjr

我无法用足够的次数来表达感谢之情。我已经花了将近两个小时来处理这个问题，它让我发疯了。 - Carlos J García

这非常有用，但是下面 @paws 的答案也让我能够在开发中测试修复。 - Obromios

@Florin，我在开发环境中遇到了相同的错误，将其添加到developmet.rb中并没有解决问题，你能否建议我需要做些什么额外的来修复这个问题，谢谢。 - opensource-developer

Answer 2

正如Uglifier官方文档所述(https://github.com/lautis/uglifier)：

“可以通过将:harmony => true选项传递给Uglifier来启用实验性的ES6语法支持。”

Uglifier.compile(js, harmony: true)

于是在config/environments/production.rb中进行替换。

config.assets.js_compressor = :uglifier

随着

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

- Guilherme Lages Santos

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被低估的答案！看起来这个支持是在Uglifier 3.2.0版本中添加的。 - randallreedjr

是的@randallreedjr...他们在3.2.0中作为实验性支持完成了。(https://www.rubydoc.info/gems/uglifier/3.2.0)它在这里工作 ;) - Guilherme Lages Santos

Answer 3

我也遇到过这个问题。

需要注意的是，Heroku 默认情况下会在生产环境中进行预编译。当你在本地运行rake assets:precompile时，通常是在开发环境下，对我来说并没有出现问题。

因此，为了在本地复制该问题，请尝试运行

RAILS_ENV=production rake assets:precompile --trace

- paws

Answer 4

在我的情况下，我正在使用angularjs-rails gem，并且以某种方式使用了es6标准，因此通过在文件config/environments/production.rb中注释掉uglify压缩器来解决它。

#config.assets.js_compressor = :uglifier

- Vivek Singh

Answer 5

似乎在使用更新的ES语法时出现了一些问题。反引号也无法预编译。

我的例子：

http://localhost:3000//${bike_file}.html

我改成了：

"http://localhost:3000//" + bike_file + ".html"

- Jbur43

Answer 6

我遇到了这个问题，它抛出了Uglifier :: Error：Unexpected token：name（subscription） 结果是一个实际的语法错误。

我不小心在一个JS文件中留下了“取消订阅”这些词，导致它抛出错误。

- ricks