Fix fs.promises ExperimentalWarning on Node 10.1.0

[bajtos]

Fixes #577

When fs-extra is loaded on Node.js 10.1.0, an experimental warning is printed:

(node:7885) ExperimentalWarning: The fs.promises API is experimental

This pull request fixes the problem by defining fs.promises as a getter property.

@RyanZim @jprichardson could you please take a look?

[coveralls]

Coverage decreased (-0.2%) to 86.826% when pulling c47822e on bajtos:fix-experimental-warning into 7d36349 on jprichardson:master.

[JPeer264]

I think, we should remove that as soon as the warning is gone in the Node core. Thoughts?

[RyanZim]

@JPeer264 Agreed, but we might still need to keep it for quite awhile, especially if all versions of Node 10 have it.

[bajtos]

I think, we should remove that as soon as the warning is gone in the Node core. Thoughts?

As a consumer of fs-extra, I am happy with removing this workaround as soon as the latest Node.js 10.x version does not print the warning.

[bajtos]

Thank you for landing and publishing my fix so quickly! ❤️ 🎉

[wangjianjun0730]

What dose it mean?And what can I do to remove this warning? The version of my node is v10.1.0.

[JPeer264]

@wangjianjun0730 this warning is due to the change from fs/promise to fs.promise. We suppressed this warning in fs-extra@6.0.1.

[archervallesfin]

Still having problem in my side still showing the warning.

[JPeer264]

You are correct critical is directly using 6.0.1. But there is another dependency, asset-resolver, which is using the version 5.0.0, I think that is causing the warning: https://github.com/addyosmani/critical/blob/master/package-lock.json#L203

[bajtos]

Because there are so many packages depending on fs-extra, I think it's pretty much impossible to get them all to upgrade fs-extra 6.x to receive the fix. I think our best option is to wait until Node.js releases the fix - see nodejs/node#20504

In loopback-next, we temporarily pinned down the Node.js version to 10.0.0 in our CI configuration to avoid the experimental warning triggered by our deep fs-extra dependencies.

[billtlee]

Hi, I just upgraded to 6.0.1 running node 10.1.0. The experimental warning went away, but the functions is not doing anything. For example

const buildPath = path.resolve(__dirname, 'build');
fs.removeSync(buildPath);

is not deleting my build directory. Is there a work around for now? I am using this to compile my files. Thanks!

[RyanZim]

@billtlee Please open a new issue with a reduced test case.