`array_pop()` in a loop is wrongly narrowing type to empty array

[mvorisek]

Bug report

https://phpstan.org/r/aad79e4f-cad2-4fe3-8248-9d94ceb5b4d4 - dumped type after array_pop() is ok, but when the array_pop() call is removed, the issue is gone. The issue is somewhere in "loop analysis".

Code snippet that reproduces the problem

https://phpstan.org/r/2524a9ad-a173-4c47-8ddf-734b1dcaff0a

Expected output

no error

[phpstan-bot]

@mvorisek After the latest push in 2.0.x, PHPStan now reports different result with your code snippet:

@@ @@
  5: Tip: Method Foo::text() always throws an exception, it should have return type "never".
  8: Variable $text in empty() always exists and is always falsy.
-15: Dumped type: array<int<0, max>, 'x'>
-17: Dumped type: array<int<0, max>, 'x'>
+15: Dumped type: list<'x'>
+17: Dumped type: list<'x'>

Full report

Line	Error
5	Tip: Method Foo::text() always throws an exception, it should have return type "never".
8	Variable $text in empty() always exists and is always falsy.
15	Dumped type: list<'x'>
17	Dumped type: list<'x'>