Support description for each x-enumNames value

[lekhmanrus]

• Enum Descriptions. The code now extracts the description from the System.ComponentModel.Description attribute for each enum value and includes it in the schema under x-enumDescriptions.
• Backward Compatibility for Enum Names. Supports JSON property names by accepting x-enumNames as well as x-enum-names and x-enum-varnames.
• Backward Compatibility for Enum Descriptions. Similarly, the schema now accepts both x-enumDescriptions and x-enum-descriptions.

Close #1156

[lahma]

Can you rebase and add a test case that shows the change?

[lekhmanrus]

Hi @lahma,
sure, done. 😊

[lahma]

LGTM, I switched to verify testing for output to get clearer picture of the output. Thank you!

[RicoSuter]

Is there a good reason why it's serialized to "x-enum-descriptions" and not "x-enumDescriptions" like in all other places (e.g. "x-enumNames")?

[lahma]

I think I googled what is the preferred and most used way and it turned out to be this, might need verification. Maybe Yet Another Configuration Option for preferred name..

[lekhmanrus]

OpenAPI 3.0 and 2.0 do not have a way to define custom names/descriptions for enum values, but some tools provide x- extensions like OpenAPI Generator, openapi-typescript-codegen, Scalar support x-enum-varnames and x-enum-descriptions
https://openapi-generator.tech/docs/templating/#enum
NSwag supports x-enumNames https://github.com/RicoSuter/NJsonSchema/wiki/Enums#enum-names-and-descriptions though.
But seems like x-enum-varnames and x-enum-descriptions are just more commonly used.

[lahma]

Maybe a PR for configurable name would be the best, closed PR usually doesn't carry far.