Allow to customize our babel configuration

[arunoda]

This works for both for all of the app pages including the custom document component.

[coveralls]

Coverage decreased (-2.4%) to 58.808% when pulling 32a1d73 on arunoda:custom-babel-config into 9ac79ed on zeit:master.

[rauchg]

do expressions 😍

[nkzawa]

This seems a bit too hacky to recommend. I wonder if the following works.

import presetStage0 from 'babel-preset-stage0'

...

config.presets.push(presetStage0)

[arunoda]

We can't import since it's next.config.js. It didn't work for me for simply giving the preset.

I will try more options.

[arunoda]

That's a pretty good option. I like it.
I thought we wanted to expose everything via next.config.js.

@rauchg what do you think?

[nkzawa]

Another idea: just use .babelrc if it exists. I can’t remember if we already discussed this option.
Then you can just set presets: ['next/babel'] to extend the default setting.

[arunoda]

That's a pretty good option. I like it.
I thought we wanted to expose everything via next.config.js.

@rauchg what do you think?

[siddharthkp]

@nkzawa, that sounds 😍
Is it safe to assume next/babel would always be applicable and apply it anyways?