Model type as an enum member

[heycalmdown]

Let's say we have an enum A;

enum A {
  AA,
  BB,
}

And a model B;

model B {
  a: A,
}

Then, a model C which extends B;

model C extends B {
  a: A.AA,
}

According to the Type relations, a can be A.AA because it can be assignable to A. It's a legit TypeSpec code, and can be compiled with @typespec/openapi3. But @azure-tools/typespec-ts emits the following error;

error @azure-tools/typespec-ts/invalid-schema: Couldn't get schema for type EnumMember

[MaryGao]

@heycalmdown Does that mean you want the sub model C has more specific value than base model B? Could you share which version and command you use to generate this code?
I tried in my local with latest emitter, and didn't find the error but with below ouput.

export interface C extends B {}

export interface B {
 /** Possible values: AA, BB */
 a: string;
}

And I think this is not perfect and we need to improve that with below output, how do you think?

export interface C extends B {
    a: "AA"
}

export interface B {
 /** Possible values: AA, BB */
 a: string; // <=== Please notice that the extensible enum would be string
}

[heycalmdown]

// main.tsp
import "@typespec/rest";

using TypeSpec.Http;

// PAYMENT_METHODS
enum PAYMENT_METHODS {
  CREDIT_CARD: "01",
}

model CommonRegistrationRequest {
  payMethod: PAYMENT_METHODS,
}

model RequestRegisterCC extends CommonRegistrationRequest {
  payMethod: PAYMENT_METHODS.CREDIT_CARD,
}

@service({})
@route("/")
namespace NicepayPlatform {
  @post
  @route("/registration")
  op Registration(@body request: RequestRegisterCC): {};
}

# tspconfig.yaml
emit:
  - '@typespec/openapi3'
  - '@azure-tools/typespec-ts'

• @azure-tools/typespec-ts" - "version": "0.13.3"
• @typespec/compiler" - "version": "0.45.2"

$ tsp compile ./typespec/test
TypeSpec compiler v0.45.2

Diagnostics were reported during compilation:

/asdf/typespec/test/main.tsp:7:3 - error @azure-tools/typespec-ts/invalid-schema: Couldn't get schema for type EnumMember
> 7 |   CREDIT_CARD: "01",
    |   ^^^^^^^^^^^^^^^^^
/asdf/typespec/test/main.tsp:7:3 - error @azure-tools/typespec-ts/invalid-schema: Couldn't get schema for type EnumMember
> 7 |   CREDIT_CARD: "01",
    |   ^^^^^^^^^^^^^^^^^
/asdf/typespec/test/main.tsp:7:3 - error @azure-tools/typespec-ts/invalid-schema: Couldn't get schema for type EnumMember
> 7 |   CREDIT_CARD: "01",
    |   ^^^^^^^^^^^^^^^^^
/asdf/typespec/test/main.tsp:7:3 - error @azure-tools/typespec-ts/invalid-schema: Couldn't get schema for type EnumMember
> 7 |   CREDIT_CARD: "01",
    |   ^^^^^^^^^^^^^^^^^

Found 4 errors.

But I could get the same output you shared despite the errors.

[MaryGao]

@heycalmdown Thanks for the info! I could re-pro it now and will work on the fix to mitigate the errors and generate like below. Let me know if you have any concern.

export interface C extends B {
    a: "AA"
}

export interface B {
   /** Possible values: AA, BB */
   a: string; 
}

And I would encourage you to add @discriminator under the type CommonRegistrationRequest to explicitly tell the compiler about the polymorphism discriminator property.

// PAYMENT_METHODS
enum PAYMENT_METHODS {
  CREDIT_CARD: "01",
}
@discriminator("payMethod")
model CommonRegistrationRequest {
  payMethod: PAYMENT_METHODS,
}

model RequestRegisterCC extends CommonRegistrationRequest {
  payMethod: PAYMENT_METHODS.CREDIT_CARD,
}

[MaryGao]

@heycalmdown we release a new version to fix this, https://www.npmjs.com/package/@azure-tools/typespec-ts/v/0.14.0. Could you have a try?

[heycalmdown]

@MaryGao it works well with the version as expected. Thanks!

[MaryGao]

Closed as resolved.