Ignore home package.json no license field

[Keraito]

Issue: Fixes #3446

If the /home/user folder contained a package.json without a license field, the installation of getstorybook is cancelled. This warning is thrown regardless of anything in the current folder that you're running getstorybook in.

Reproduction would be to create a package.json without a license field in your home directory, initialize a project that would normally work with getstorybook, like through create-react-app, and then run getstorybook.

This is caused by the checking of the version of the generator dependencies which resulted in the warning being thrown and thus existing the installation at https://github.com/storybooks/storybook/blob/3539625d7f801a0fee1fb8c58f1ff57016c9513f/lib/cli/lib/latest_version.js#L34
(Thanks to @sunilhari for pointing this out).
In fact, if you for whatever reason have a package.json at your home directory without a license field (or anywhere along the path towards the current directory), the warning will be thrown at any yarn command. The result of actually running the command, however, is then outputted after the warning:

What I did

Using the knowledge from the screenshot above, I basically added an array of warning texts that will not stop the entire installation process.

This fix is entirely based on yarn and I did not check yet how this works with npm and if there are any differences. But I wanted to open this PR in order to see whether this solution is desired before spending more time on it.

[Hypnosphi]

I did not check yet how this works with npm

Please do that

[Hypnosphi]

Should we maybe just ignore "type": "warning"?

[Keraito]

@Hypnosphi

Please do that

Running npm info babel-runtime version does not raise a warning for a missing license field in package.json in the home directory, so this is an yarn only issue as far as I can observe. Nonetheless, I also did a full getstorybook installation with npm, and all of it works.

While I did this, I noticed that the checking of the package versions is always done with yarn if it's installed (https://github.com/storybooks/storybook/blob/master/lib/cli/lib/latest_version.js#L4), and that the --use-npm flag is only pointed at the installation of dependencies. Is this intended? I'm not sure if old versions of yarn will cause issues with it, like what was seen with issues related to #3453.

Should we maybe just ignore "type": "warning"?

That would be easier yes, but is every warning from yarn/npm/both ones that can be ignored for the installation of storybook? Asking because I don't have sufficient knowledge of all specifics of both package manager to be able to answer that.

[Hypnosphi]

While I did this, I noticed that the checking of the package versions is always done with yarn if it's installed (https://github.com/storybooks/storybook/blob/master/lib/cli/lib/latest_version.js#L4), and that the --use-npm flag is only pointed at the installation of dependencies.

It would make sense to include --use-npm check to has_yarn helper (and probably rename it to use_yarn
https://github.com/storybooks/storybook/blob/master/lib/cli/lib/has_yarn.js

is every warning from yarn/npm/both ones that can be ignored for the installation of storybook?

In this particular helper we only want to catch the fact that a package isn't published. User will still see the warnings when the actual installation will happen.

[Keraito]

In this particular helper we only want to catch the fact that a package isn't published. User will still see the warnings when the actual installation will happen.

Makes sense, will change it to ignore yarn warnings in general then.

It would make sense to include --use-npm check to has_yarn helper (and probably rename it to use_yarn

Does it make sense to put this change into another PR, or should I include it here?

[codecov]

Codecov Report

Merging #3531 into master will decrease coverage by <.01%.
The diff coverage is 0%.

@@            Coverage Diff            @@
##           master   #3531      +/-   ##
=========================================
- Coverage   37.61%   37.6%   -0.01%     
=========================================
  Files         459     459              
  Lines       10377   10378       +1     
  Branches      928     927       -1     
=========================================
  Hits         3903    3903              
+ Misses       5932    5931       -1     
- Partials      542     544       +2

Impacted Files	Coverage Δ
lib/cli/lib/latest_version.js	0% <0%> (ø)	⬆️
lib/ui/src/modules/ui/components/layout/usplit.js	38.7% <0%> (ø)	⬆️
lib/ui/src/modules/ui/routes.js	0% <0%> (ø)	⬆️
lib/ui/src/modules/ui/containers/layout.js	20% <0%> (ø)	⬆️
app/react-native/src/server/addons.js	0% <0%> (ø)	⬆️
lib/ui/src/modules/ui/components/header.js	25.71% <0%> (ø)	⬆️
lib/ui/src/modules/shortcuts/index.js	18.18% <0%> (ø)	⬆️
addons/knobs/src/components/PropField.js	10.63% <0%> (ø)	⬆️
addons/storyshots/src/rn/loader.js	53.33% <0%> (ø)	⬆️
addons/knobs/src/components/types/Boolean.js	11.62% <0%> (ø)	⬆️
... and 75 more

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[Hypnosphi]

Does it make sense to put this change into another PR, or should I include it here?

I'm ok with both, please do whatever you're more comfortable with

[Hypnosphi]

info.type === 'error' would be more explicit

[Keraito]

I'm ok with both, please do whatever you're more comfortable with

I will do it in another PR as at first glans it looks like the change will not be very trivial, isn't necessarily related to the original issue, and I don't want to block this patch cuz of it.

info.type === 'error' would be more explicit

Changed it