Fix statement analysis after early-terminating statements

[takaram]

Closes phpstan/phpstan#11179

[ondrejmirtes]

Please also add a test into the "Unreachable statement - code above always terminates." rule.

[takaram]

It's in UnreachableStatementRuleTest

[ondrejmirtes]

Sorry, I don't understand these changes. So here we're going to invoke UnreachableStatementNode but then we're still going to analyse the next statement if it's not Function_ or ClassLike? I don't get it.

[takaram]

Given this code:

<?php
namespace Foo;

doSomething();
exit();
foo();
bar();

function doSomething(): void
{
  // ...
}

Here foo(); will be reported as an unreachable statement.
Before this PR, PHPStan stops analyzing statements after foo() because analyzing bar() is no longer useful.
However, we still need to analyze the body of doSomething() actually.

So PHPStan should continue analysis after an unreachable statement, but the target is different;

• Before unreachable statements ($alreadyTerminated = false)
  • analyze all statements
• After unreachable statements ($alreadyTerminated = true)
  • analyze only functions and class-likes

[staabm]

what about methods, closures, arrow-functions?

[ondrejmirtes]

@staabm 1) I don't think you can put exit in-between methods in a class
2) I don't think closures after exit are executed.

[ondrejmirtes]

@takaram Thank you, makes total sense!

[ondrejmirtes]

Thank you!