Bug report

See snippet

Code snippet that reproduces the problem

https://phpstan.org/r/4e66f143-edf6-4275-a581-3378674498b9

Expected output

array{a?: array{x: 1, y: 2}, b?: array{x: 1, y: 2}}

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