Strict comparison using === between NAN and NAN will always evaluate to false

[gnutix]

Bug report

Hello there!

I've just upgraded to the latest and greatest version of PHPStan (1.10.50) and this issue appeared :

Parameter #1 $array of function collectWithKeys expects array<'Not a Number', NAN>, array{Not a Number: NAN} given.

Code snippet that reproduces the problem

https://phpstan.org/r/8b7e5238-b4a6-46c9-9fc3-0ef7c3b2343e

Expected output

There should be no errors.

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[ondrejmirtes]

I think the underlying issue is simply this: https://phpstan.org/r/5cff9af9-ecef-422d-8a7b-606e25c33b78

And must be fixed in ConstantFloatType in accepts and isSuperTypeOf methods.

[LeoVie]

I think the underlying issue is simply this: https://phpstan.org/r/5cff9af9-ecef-422d-8a7b-606e25c33b78

Isn't this behaviour correct, as NAN === NAN will indeed always evaluate to false?

https://3v4l.org/ACgGt

[phpstan-bot]

@ondrejmirtes @LeoVie After the latest push in 1.11.x, PHPStan now reports different result with your code snippet:

@@ @@
+7: Expression "\NAN === \NAN" on a separate line does not do anything.
 7: Strict comparison using === between NAN and NAN will always evaluate to false.

Full report

Line	Error
7	Expression "\NAN === \NAN" on a separate line does not do anything.
7	Strict comparison using === between NAN and NAN will always evaluate to false.

[ondrejmirtes]

Fixed phpstan/phpstan-src#3036

[github-actions]

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