False positive when for in_array check with complex code path

[Seldaek]

See https://phpstan.org/r/c93e00ea-82a6-484a-b1e6-ac2a4f443693

The in_array() warning is wrong there at the end, as 10 may or may not be inside array{0: 10|20, 1?: 20} (which could be array{0: 20} for example.

In case it's more readable or to understand what the code does it comes from https://github.com/composer/composer/blob/6be6ce7d9f911c248139976703b73f4876c8a38f/src/Composer/Downloader/PathDownloader.php#L254-L279 originally.

[phpstan-bot]

@Seldaek After the latest push in 1.8.x, PHPStan now reports different result with your code snippet:

@@ @@
-17: Dumped type: array{0: 10|20, 1?: 20}
+17: Dumped type: array{0: 10, 1?: 20}|array{20}
 18: Dumped type: 10|20
-21: Dumped type: array{0: 10|20, 1?: 20}
-22: Dumped type: 10
-23: Call to function in_array() with arguments 20, array{0: 10|20, 1?: 20} and true will always evaluate to true.
+21: Dumped type: array{0: 10, 1?: 20}|array{20}
+22: Dumped type: 10

Full report

Line	Error
17	`Dumped type: array{0: 10, 1?: 20}
18	`Dumped type: 10
21	`Dumped type: array{0: 10, 1?: 20}
22	Dumped type: 10

[github-actions]

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