Rule proposal: `no-implicit-parent-communication`

[michalsnik]

Style guide:
https://vuejs.org/v2/style-guide/#Implicit-parent-child-communication-use-with-caution

Description:
This rule would disallow usage of this.$parent in vue components. It is recommend to use props instead.

There are few cases when it's better to use this.$parent though, but it's better to make a conscious decision after seeing a warning than directly relying on parent.

[mateuszRybczonek]

I will start working on that one.

[chrisvfritz]

This sounds good. 🙂 Unfortunately, situations where it might be OK to use $parent are probably too subjective to put this in any category, so I think this should probably an an uncategorized opt-in.

[armano2]

@mateuszRybczonek are you working on it?