Implement scalaImports trait

[lenguyenthanh]

This is to implement scalaImports trait, which provides mechanism to add an import to a specific generated structure from smithy. The rationale behind is on this discussion.

I still need to check all the items below but want to make a draft PR first to gather some early feedback.

ps: You can see this pr in action here: lenguyenthanh/fide#100

PR Checklist (not all items are relevant to all PRs)

• Added unit-tests (for runtime code)
• Added bootstrapped code + smoke tests (when the rendering logic is modified)
• [ ] Added build-plugins integration tests (when reflection loading is required at codegen-time)
• [ ] Added alloy compliance tests (when simpleRestJson protocol behaviour is expanded/updated)
• [ ] Updated dynamic module to match generated-code behaviour
• Added documentation
• Updated changelog

[Baccata]

Looks good to me. The only other thing that I'd add would be some smoke tests, namely adding some specs in sampleSpecs folder that will be generated during the compilation of the bootstrapped module.

If you can reproduce a minimal spec showcasing the problem that led you to issue this PR, and how it can be fixed with this new trait, I'll deem the PR mergeable 👍

[lenguyenthanh]

Looks good to me. The only other thing that I'd add would be some smoke tests, namely adding some specs in sampleSpecs folder that will be generated during the compilation of the bootstrapped module.

Thanks, I was looking at how to do smoke tests, but couldn't find. I'll add it today.

If you can reproduce a minimal spec showcasing the problem that led you to issue this PR, and how it can be fixed with this new trait, I'll deem the PR mergeable 👍

Should I write this in to a docs? probably 04-codegen/01-customisation/15-scala-imports.md?

[lenguyenthanh]

Added a minimal smoke test for this. And it also shows We can see why this We need this feature.

@scalaImports(["smithy4s.refined.Age.provider._"])
structure StructureWithScalaImports {
  @range(min: 13, max: 19)
  teenage: Age
}

This wouldn't compiled without the needed provider(which is delivered by scalaImports trait):

    implicit val rangeProvider: RefinementProvider.Simple[smithy.api.Range, Age] =
      RefinementProvider.rangeConstraint(x => x.value)

[lenguyenthanh]

So, I think this is done code wise, now times for some documentation and change log. Is this okay better to do those in another PR and let this one going first?

[Baccata]

@lenguyenthanh I'd rather the docs were added to this PR, to be honest.

Should I write this in to a docs? probably 04-codegen/01-customisation/15-scala-imports.md?

This is a fine place, yes 👍

[lenguyenthanh]

cool, I'll add it tomorrow.

[lenguyenthanh]

Added documentation, and updated changelog. Tested by building the website locally. Please help me improve those docs 🙏

[Baccata]

The documentation is great, thank you very much !

[lenguyenthanh]

thanks for your guidelines @Baccata . It was fun!