Swift5 models improvements

[aymanbagabas]

• Add the option to use final class instead of struct
• Always include CodingKeys
• Implement equals and hash funcs
• Encode null values
• Add useClasses to urlsessionLibrary config
• Add a required nullable test case to 2_0/swift/petstore*.yaml

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[aymanbagabas]

Dependencies ready!
I need the list of published packages to verify your dependencies, so I tried to
fetch:

    https://package.elm-lang.org/all-packages

But it came back as 502 Bad Gateway

Good times!

[4brunu]

I'm a bit tired today, so tomorrow I will review this more carefully, but some initial thoughts, is that I thinks we shouldn't create the equals and hash functions on structs, because they are given automatically for free.

[aymanbagabas]

I thinks we shouldn't create the equals and hash functions on structs, because they are given automatically for free.

You're correct, structs have a default implementation of func == and hash(to:). PR updated.

[4brunu]

I think that maybe you forgot to update the sample projects, because the structs are still implementing equals and hash functions

[wing328]

Please resolve the merge conflicts when you've time.

[wing328]

Add a required nullable test case to 2_0/swift/petstore*.yaml

I think you will need to do it in the OpenAPI 3.0 spec instead as nullable is only officially support in 3.0 but not 2.0

[aymanbagabas]

I think you will need to do it in the OpenAPI 3.0 spec instead as nullable is only officially support in 3.0 but not 2.0

I think this is fine since OAS 2.0 x-nullable gets mapped to OAS 3.0 nullable, right? Plus currently, there isn't a 3_0/swift/petstore*.yaml specs file.

[wing328]

I think this is fine since OAS 2.0 x-nullable gets mapped to OAS 3.0 nullable, right? Plus currently, there isn't a 3_0/swift/petstore*.yaml specs file.

We are actually move away from 2.0 spec and use mainly 3.0 for samples. Don't worry about it now. I'll do the migration later.

Please resolve the merge conflicts when you've time