KTOR-9451 Support nested generic types

[bjhham]

Subsystem
Server, OpenAPI (Schema)

Motivation
KTOR-9451 OpenAPI schema inference not working for custom nested generics

Solution
We were previously only checking if the supplied KType was parameterized, but this logic doesn't work for multiple levels of generics. To account for this, we need to initially traverse the type argument tree to populate a lookup of KTypes, because the generated serializers' descriptors have no way of introspecting on this.

Additionally, I noticed that generics were only supported for collection types on the reflection schema inference side, so I also fixed this.

[coderabbitai]

Important

Review skipped

Draft detected.

Please check the settings in the CodeRabbit UI or the .coderabbit.yaml file in this repository. To trigger a single review, invoke the @coderabbitai review command.

⚙️ Run configuration

Configuration used: Path: .coderabbit.yaml

Review profile: CHILL

Plan: Pro

Run ID: 79bb553a-1a4c-477e-a2ab-f1652a857790

You can disable this status message by setting the reviews.review_status to false in the CodeRabbit configuration file.

Use the checkbox below for a quick retry:

• 🔍 Trigger review

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch bjhham/nested-generics-schema

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands and usage tips.}