MobX failed to load / unexpected token

[winkler1]

I'm on an old version of MobX, 4.0.0, and got this--

[snowpack] Failed to load node_modules/mobx/lib/mobx.module.js
Unexpected token (3978:69) in /node_modules/mobx/lib/mobx.module.js

This turns out to be a comment: console.warn("[mobx] you are running a minified build, but 'process.env.NODE_ENV' was not set to 'production' in your bundler. This results in an unnecessarily large and slow bundle");

My guess: some regex code, not AST, is not grok'ing NODE_ENV is within a quoted string?

[FredKSchott]

oh interesting. Are you on the latest version of Snowpack? This used to be an issue, but we now use an AST-based process polyfill for this reason.

See esinstall/src/rollup-plugins/rollup-plugin-node-process-polyfill.ts

[winkler1]

Happens with both 2.18.2 and 3.0.0-rc.1. Tried to log new Error().stack to see where it originated, no luck. Should be repro'able with mobx 4.0.0 in package.json, at least...

[FredKSchott]

Great, I'll try to dig in and take a look when I can

[winkler1]

Workaround -
sed -i -- "s/'process.env.NODE_ENV'/'process-env-NODE_ENV'/g" node_modules/mobx/lib/mobx.module.js

[FredKSchott]

Can you upgrade mobx? On 5.x I see:

console.warn("[mobx] you are running a minified build, but '" + varName + "' was not set to 'production' in your bundler. This results in an unnecessarily large and slow bundle");

And on 6.0 that file no longer exists

[winkler1]

Will try. I've been hair-on-fire excited about this crazy new thing called snowpack for the last week, but should have time now :)