DynamicFunctionReturnTypeExtension for the get_debug_type function.

[patrickkusebauch]

Closes: phpstan/phpstan#10558
Closes: phpstan/phpstan#10585

[phpstan-bot]

You've opened the pull request against the latest branch 1.11.x. If your code is relevant on 1.10.x and you want it to be released sooner, please rebase your pull request and change its target to 1.10.x.

[patrickkusebauch]

Looking at the failing checks, none of them seem to be genuinely caused by this change.

[staabm]

Please add a pattern-matching example-test and use it in rule-tests which emit errors before this PR and are expected to be fixed now

[patrickkusebauch]

Please add a pattern-matching example-test and use it in rule-tests which emit errors before this PR and are expected to be fixed now

Updated the PR.

Error emitted before this PR: '20: Match expression does not handle remaining value: string'.

[patrickkusebauch]

Updated to also specify the type in condition branches. This closes phpstan/phpstan#10585 for me.

I have a question about TypeTraverser::map and TypeCombinator::union. I tried to replicate the code in GettypeFunctionReturnTypeExtension as it is a similar feature. However, when trying to combine:

• 'bool'|string (constant string bool or any string) it gets normalized to string
• 'Namespace\ClassA'|'Namespace\ClassB' (constant strings with FQCN) it gets normalized to Namespace\ClassA|Namespace\ClassB

Is this expected? Can this be turned off? Are those considered equivalent?