将Rails应用程序部署到Heroku时出现语法错误：ExecJS :: RuntimeError：SyntaxError：Unexpected character

Question

I am trying to deploy my app to Heroku but its throwing me this error.

"ExecJS::RuntimeError: SyntaxError: Unexpected character '`' (line: 14577, col: 33, pos: 440811"

I assume there is something wrong with the coffeescript/javascript. I have deleted all of my coffeescript files and I dont know what I'm doing wrong.

As suggested by Iceman, ive tried running the command

rake assets:precompile RAILS_ENV=development

and it says

I, [2017-01-26T16:32:25.173928 #2674] INFO -- : Writing >/Users/Gana/Documents/bombay/bombaydarbar/public/assets/circle->cb2239e32deac2eba5c693c3574b562595f1f933a8896866e47c170bf87c77e4.png I, [2017-01-26T16:32:25.209986 #2674] INFO -- : Writing >/Users/Gana/Documents/bombay/bombaydarbar/public/assets/fb->e361b3ecca9c24c6c05646b170fe25fcc185fa2eafb7aa46780253c8a9c79a04.png I, [2017-01-26T16:32:25.225079 #2674] INFO -- : Writing >/Users/Gana/Documents/bombay/bombaydarbar/public/assets/los->f083228761f6ede67e04a1a73906b4585bc5cfd3154ffec4861c4f04cf95aa32.jpg I, [2017-01-26T16:32:25.253212 #2674] INFO -- : Writing >/Users/Gana/Documents/bombay/bombaydarbar/public/assets/main->221235002689ad3847a67a05ce3608ebed4ee709be6fcf61bc0ccef2001b487f.jpg I, [2017-01-26T16:32:25.272155 #2674] INFO -- : Writing /Users/Gana/Documents/bombay/bombaydarbar/public/assets/us-background-638489d758e08327ad62f883f11397bc870df84038b502ea17c3e2510cac6ef4.jpg I, [2017-01-26T16:32:25.313969 #2674] INFO -- : Writin g /Users/Gana/Documents/bombay/bombaydarbar/public/assets/zaisan-5f83c22eef3372c96199aad34ab9ad1744d6124e845a01267fcabcec39e2e948.jpg I, [2017-01-26T16:32:25.426829 #2674] INFO -- : Writing /Users/Gana/Documents/bombay/bombaydarbar/public/assets/application-cadb51eb7487d2788eae31912fc18cc28ffaf8d48ea022d2a8a49c121415d7f8.js I, [2017-01-26T16:32:25.427380 #2674] INFO -- : Writing /Users/Gana/Documents/bombay/bombaydarbar/public/assets/application-cadb51eb7487d2788eae31912fc18cc28ffaf8d48ea022d2a8a49c121415d7f8.js.gz I, [2017-01-26T16:32:25.540537 #2674] INFO -- : Writing /Users/Gana/Documents/bombay/bombaydarbar/public/assets/application-8b6461ded0e51f6232fa5606fc47c47cd9b64684fbbeccd9fed16d7a0a66deee.css I, [2017-01-26T16:32:25.540807 #2674] INFO -- : Writing /Users/Gana/Documents/bombay/bombaydarbar/public/assets/application-8b6461ded0e51f6232fa5606fc47c47cd9b64684fbbeccd9fed16d7a0a66deee.css.gz I, [2017-01-26T16:32:25.543684 #2674] INFO -- : Writing /Users/Gana/Documents/bombay/bomba ydarbar/public/assets/fontawesome-webfont-7bfcab6db99d5cfbf1705ca0536ddc78585432cc5fa41bbd7ad0f009033b2979.eot I, [2017-01-26T16:32:25.597933 #2674] INFO -- : Writing /Users/Gana/Documents/bombay/bombaydarbar/public/assets/fontawesome-webfont-7bfcab6db99d5cfbf1705ca0536ddc78585432cc5fa41bbd7ad0f009033b2979.eot.gz I, [2017-01-26T16:32:25.601098 #2674] INFO -- : Writing /Users/Gana/Documents/bombay/bombaydarbar/public/assets/fontawesome-webfont-2adefcbc041e7d18fcf2d417879dc5a09997aa64d675b7a3c4b6ce33da13f3fe.woff2 I, [2017-01-26T16:32:25.638449 #2674] INFO -- : Writing /Users/Gana/Documents/bombay/bombaydarbar/public/assets/fontawesome-webfont-ba0c59deb5450f5cb41b3f93609ee2d0d995415877ddfa223e8a8a7533474f07.woff I, [2017-01-26T16:32:25.675384 #2674] INFO -- : Writing /Users/Gana/Documents/bombay/bombaydarbar/public/assets/fontawesome-webfont-aa58f33f239a0fb02f5c7a6c45c043d7a9ac9a093335806694ecd6d4edc0d6a8.ttf I, [2017-01-26T16:32:25.716776 #2674] INFO -- : Writing /Users/Gana/Documents/b ombay/bombaydarbar/public/assets/fontawesome-webfont-aa58f33f239a0fb02f5c7a6c45c043d7a9ac9a093335806694ecd6d4edc0d6a8.ttf.gz I, [2017-01-26T16:32:25.721169 #2674] INFO -- : Writing /Users/Gana/Documents/bombay/bombaydarbar/public/assets/fontawesome-webfont-ad6157926c1622ba4e1d03d478f1541368524bfc46f51e42fe0d945f7ef323e4.svg I, [2017-01-26T16:32:25.808396 #2674] INFO -- : Writing /Users/Gana/Documents/bombay/bombaydarbar/public/assets/fontawesome-webfont-ad6157926c1622ba4e1d03d478f1541368524bfc46f51e42fe0d945f7ef323e4.svg.gz

is there something wrong with my image files?

Answer 1

The problem, as some of the users has mentioned, is Rails JS uglifier not being able to handle ES6 template literals.

Uglifier now has a Harmony mode which supports ES6 / ES2015+ syntax.

You can enable it by passing :harmony => true option to Uglifier.

Open config/environments/production.rb

Replace

config.assets.js_compressor = :uglifier

with

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

Answer 2

I'm facing a similar error, it seems like Rails JS uglifier can't handle ES6 template literals . You might need to replace "`" (template literals) with single or double quotes. In case you want to verify, copy paste your problematic JS (you'll have to search for "`" in your JS directory) file here https://jscompress.com/ and see the error.