Rule proposal: `no-unnecessary-negation`

Description

This rule would enforce users to simplify negations: !(a === b) -> a !== b. There might be other conditions like this that could be simplified.

Fail

if (!(a > b)) {}
const foo = !(bar === baz);
const foo = !(typeof bar === 'undefined');

Pass

if (a <= b) {}
const foo = bar !== baz;
const foo = typeof bar !== 'undefined';
const foo = !Array.isArray(bar);

[noftaly]

You have to be careful simplifying expressions with - and + because of automatic type inference. There are edge cases where a - -b is not the same as a + b

> 3 - -[]
3
> 3 + []
'3'
> 3 - -{}
NaN
> 3 + {}
'3[object Object]'
> 3 - -Number
NaN
> 3 + Number
'3function Number() { [native code] }'

[jguddas]

The code is not in a presentable state, but it works 🎉

https://astexplorer.net/#/gist/c922ca1591e8db763030071c09df875a/3865211cf9b06a03034a0b199d0e65f6ff8f49c5

Please let me know when you find something that does not work as you expect and generally what you have tried out, so we can include that in our test cases.