Honor custom types for array items

[kelnos]

Previously this only worked for protocol objects; now it also works for parameters and in-line request bodies.

Addresses #738

[kelnos]

I don't love arrayTypeLifter, but one of my goals here was to use the same type resolution code for protocol objects and parameters. The issue here is that for protocol objects we want to use a concrete type like Vector, but for client parameters, we don't care which type the caller passes, so we want to use Iterable.

[kelnos]

Hrm, it appears that this ends up using the abstract container type for server routes, which almost certainly will not work.

[kelnos]

Actually, I guess that was always happening. For Java stdlib it's not a problem since it's always a concrete type, and I guess for the Scala stuff the routes don't have types listed? But for Java Vavr I'm using Seq now, which will not work. I guess I can go back to Vector. Hrm.

[kelnos]

Ugh, so this does seem to break things, but because we were arguably doing questionably-wrong things previously. Every array param was always Iterable[String] even when it was not a string. I guess we just never had tests for those cases?

But now that it does the right thing, the defaults break when the real type isn't String, e.g.:

[error] /home/brian/src/twilio/guardrail/modules/sample-akkaHttp/target/generated/examples/client/akkaHttp/pet/PetClient.scala:88:61: type mismatch;
[error]  found   : String("available")
[error]  required: examples.client.akkaHttp.definitions.PetStatus
[error]   def findPetsByStatus(status: Iterable[PetStatus] = Vector("available"), headers: List[HttpHeader] = Nil): EitherT[Future, Either[Throwable, HttpResponse], FindPetsByStatusResponse] = {

And also it can't properly generate routes on the server for non-string params:

[error] /home/brian/src/twilio/guardrail/modules/sample-akkaHttp/target/generated/issues/issue249/server/akkaHttp/Routes.scala:35:106: type mismatch;
[error]  found   : akka.http.scaladsl.common.RepeatedValueReceptacle[issues.issue249.server.akkaHttp.definitions.Baz]
[error]  required: akka.http.scaladsl.server.directives.ParameterDirectives.ParamSpec
[error]       path("foo")(get(parameter(Symbol("bar").as[_root_.issues.issue249.server.akkaHttp.definitions.Baz].*).map(xs => Option(xs).filterNot(_.isEmpty).map(x => x.toVector)).apply(bar => discardEntity(complete(handler.doFoo(DoFooResponse)(bar))))))

[kelnos]

I'm actually surprised the latter thing doesn't work, because I thought you were generating akka unmarshallers automatically from circe decoders?

[blast-hardcheese]

@kelnos This is definitely done for non-array members, though I've had to restrict the Directives stuff quite a bit to prevent overeager JSON decoders, for instance requiring JSON-encoded path parameters like /foo/%22bar%22/baz (JSON string literals, including quotes)

I'll take a look at this sometime this week, thank you for driving this

[kelnos]

Ah, makes sense. Just to summarize, there are three issues:

1. This will cause server parameters to use the 'abstract' type Iterable for the types of route params, which definitely will break Java Vavr, not sure about others.
2. Scala default arg values are now broken when the type isn't String.
3. akka-http doesn't have the required unmarshallers in place to handle e.g. enum query parameters.

[blast-hardcheese]

Going to close this in favor of #1407, all functionality here should be reflected in the new unified codepath.