[OCaml] Introduce support for oneOf/anyOf, fix default value for non-required maps

[sir4ur0n]

⚠️ Depends on #21681, please review/merge #21681 first

💡 Review commit by commit for easier review

• Add a first (probably not perfect) version of support for oneOf/anyOf
• Fix a bug I just discovered (while trying to manually test the oneOf feature on some big openapi.json) where non-required maps are missing a @default in models
• Fix a bug where maps are incorrectly encoded/decoded

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[sir4ur0n]

@cgensoul

[wing328]

i'll get this merged first and later maybe come up with a PR to remove these blank lines

curious are you using any linter to format the auto-generated code as part of your development workflow?

[sir4ur0n]

Are you talking about the blank lines in the Mustache files, or in the generated OCaml files?
I think the Mustache files being easy to read is quite important for maintainability 😅
On the other hand, the generated OCaml files being ugly is - in my opinion - not such a big deal because I think almost all projects use a formatter (most often ocamlformat).

I would be happy (probably in another MR) to add an .ocamlformat file + automatically format OCaml files (either directly from openapi-generator but it means it becomes a dependency, or only for the generated files versioned in this Git repo, you tell me)

[wing328]

Are you talking about the blank lines in the Mustache files, or in the generated OCaml files?

Generated OCaml files

I think the Mustache files being easy to read is quite important for maintainability 😅

Totally agreed.

On the other hand, the generated OCaml files being ugly is - in my opinion - not such a big deal because I think almost all projects use a formatter (most often ocamlformat).

Nice

I would be happy (probably in another MR) to add an .ocamlformat file

Yes, nice to include one