[!] (plugin closure-compiler) SyntaxError: Unexpected token (460:13) undefined (460:13)

[mohe2015]

What's the issue?

Crashes with

[!] (plugin closure-compiler) SyntaxError: Unexpected token (460:13)
undefined (460:13)
SyntaxError: Unexpected token (460:13)
    at Parser.pp$4.raise (/home/moritz/Documents/projektwahl-lit/node_modules/acorn/dist/acorn.js:2927:15)
    at Parser.pp.unexpected (/home/moritz/Documents/projektwahl-lit/node_modules/acorn/dist/acorn.js:698:10)
    at Parser.pp.expect (/home/moritz/Documents/projektwahl-lit/node_modules/acorn/dist/acorn.js:692:28)
    at Parser.pp$3.parseMethod (/home/moritz/Documents/projektwahl-lit/node_modules/acorn/dist/acorn.js:2713:10)
    at Parser.pp$1.parseClassMethod (/home/moritz/Documents/projektwahl-lit/node_modules/acorn/dist/acorn.js:1399:25)
    at Parser.pp$1.parseClassElement (/home/moritz/Documents/projektwahl-lit/node_modules/acorn/dist/acorn.js:1388:10)
    at Parser.pp$1.parseClass (/home/moritz/Documents/projektwahl-lit/node_modules/acorn/dist/acorn.js:1326:26)
    at Parser.pp$1.parseStatement (/home/moritz/Documents/projektwahl-lit/node_modules/acorn/dist/acorn.js:842:19)
    at Parser.pp$1.parseTopLevel (/home/moritz/Documents/projektwahl-lit/node_modules/acorn/dist/acorn.js:755:23)
    at Parser.parse (/home/moritz/Documents/projektwahl-lit/node_modules/acorn/dist/acorn.js:555:17)

How do we reproduce the issue?

git clone https://github.com/projektwahl/projektwahl-lit.git
cd projektwahl-lit
git checkout 68d1c1b28382a127511d1b8a9eb77006426afc92
npm install
npm run localize-build
npm run rollup

Additional information

I think this may be because of the outdated acorn dependency and may simply be fixed by updating it.

[danimoh]

I ran into the same issue with the usage of modern JS features, in my case class fields.
As I'm using typescript in my project, I could set its target to ES2017 to transpile my code down to that older ES version that the used acorn version still understands.
I did not experiment with updating acorn, but I too believe that it's probably the cause of the described issue.

If you want to figure out what code is triggering the issue in your case, you can patch your node_modules/acorn/dist/acorn.js:2927:15 with a console.log(this.input);.

[eguneys]

Please fix this asap....