Fix Includes null includes undefined

[JonghwanWon]

I modified what passes when null includes undefined.

[sindresorhus]

Can you explain your change? Why does changing the order fix the issue?

[JonghwanWon]

Can you explain your change? Why does changing the order fix the issue?

Hello, @sindresorhus thank your comment. First at all, My English is not good. so, I attached source code. Please forgive me if there are any mistakes.

I've distinguished the old 'Includes' from the changed 'Includes' for comparison.

type T1= IsEqual<null, null>  // true
type T2= IsEqual<undefined, undefined>  // true
type T3= IsEqual<null, undefined>  // false

type T4 = OldIncludes<[null], null>  // true
type T5 = NewIncludes<[null], null>  // true

type T6 = OldIncludes<[undefined], undefined>  // true
type T7 = NewIncludes<[undefined], undefined>  // true

type T8 = OldIncludes<[null], undefined>  // Expected to be "false". but type is "true"
type T9 = NewIncludes<[null], undefined>  // false

I thought it was strange that the result was different when I ended up using isEqual depending on the internal behavior in Includes.