Result in syntax error when serializing instanceof {expression}

[ralphjsmit]

Hello, I noticed that when serializing any instanceof with the result being an expression fails.

For example, code that fails is:

$this instanceof (Foo::class)

Practical example:

if ($this instanceof (class_exists(Foo::class) ? Foo::class : Bar::class)) {}

This type of code gets compiled into:

fn (\Foo\Bar $a) => $this instanceof \Foo\Bar (\Foo\Baz\Qux\Forest::class)

Basically, it seems like the serializable closure takes the last class that it replaced/imported the full namespace for, and puts it after the instanceof and before the expression, thus resulting in this syntax error: $this instanceof \Foo\Bar (...).

I first added a failing test to identify it. Then I looked into if I could pinpoint the issue, but unfortunately I did not find it myself. If someone with good knowledge of this could pinpoint me to the correct place where to make the fix would be awesome. Also, feel free to take over the PR.

Thanks!

[schaper1337]

Good find :)