In chroot environments, npm run build fails

[vielhuber]

Version

3.0.0-rc.11

Node and OS info

Node 10.8.0 / npm 6.2.0 / Ubuntu 16 64-bit

Steps to reproduce

In a chroot environment, where /proc etc. is not available, require('os').cpus() returns undefined.

If we run npm run build, we get the following error:

ERROR TypeError: Cannot read property 'length' of undefined
TypeError: Cannot read property 'length' of undefined
at exports.defaults (/xxx/node_modules/@vue/cli-service/lib/options.js:77:33)

If we change the line 77 of options.js to

parallel: require('os').cpus() !== undefined && require('os').cpus().length > 1,

it works.

There is only another small error in uglifyjs-webpack-plugin (where again some kind of cpu function is used without checking if it returns undefined), but I will open up another support ticket there.

Can you please improve this line of code?

What is expected?

Normal build process

What is actually happening?

Error in options.js line 77.