[BUG] `type.type.startsWith not a function` for type-of+enum inside parameters

[bugwelle]

Is there an existing issue for this?

• [X] I have searched the existing issues

Nature of Your Project

JavaScript

Current Behavior

Given following CDS snippet:

entity EnumTypeOf {
  str: String;
}

service EnumsInActions {

  action EnumInParamAndReturn(
    Param: EnumTypeOf:str enum { a; }
  ) returns String;

}

using cds-type's CLI, it crashes:

$ ./lib/cli.js --outputDirectory tmp --propertiesOptional true Enums.cds
[ERROR] Derived singular 'EnumTypeOf' for your entity 'EnumTypeOf', already exists. The resulting types will be erronous. Consider using '@singular:'/ '@plural:' annotations in your model or move the offending declarations into different namespaces to resolve this collision.
/Users/<dir>/cds-typer/lib/visitor.js:322
        return type.enum && type.type.startsWith('cds.')
                                      ^

TypeError: type.type.startsWith is not a function
    at #stringifyFunctionParamType (/Users/<dir>/cds-typer/lib/visitor.js:322:39)
    at /Users/<dir>/cds-typer/lib/visitor.js:314:53
    at Array.map (<anonymous>)
    at #stringifyFunctionParams (/Users/<dir>/cds-typer/lib/visitor.js:312:18)
    at #printFunction (/Users/<dir>/cds-typer/lib/visitor.js:332:53)
    at Visitor.visitEntity (/Users/<dir>/cds-typer/lib/visitor.js:413:36)
    at Visitor.visitDefinitions (/Users/<dir>/cds-typer/lib/visitor.js:96:22)
    at new Visitor (/Users/<dir>/cds-typer/lib/visitor.js:85:14)
    at compileFromCSN (/Users/<dir>/cds-typer/lib/compile.js:68:23)
    at compileFromFile (/Users/<dir>/cds-typer/lib/compile.js:50:12)

Node.js v20.11.1

Expected Behavior

I expected the CLI to not crash and to end up with valid TypeScript files. Related issue (without the crash). https://github.com/cap-js/cds-typer/issues/169

Steps To Reproduce

1. Create a file Enum.cds with:

entity EnumTypeOf {
  str: String;
}

service EnumsInActions {

  action EnumInParamAndReturn(
    Param: EnumTypeOf:str enum { a; }
  ) returns String;

}

2. Inside this repository, run $ ./lib/cli.js --outputDirectory tmp --propertiesOptional true Enums.cds
3. See crash

Environment

• OS: macOS
• Node: v20
• npm: 10.4.0
• cds-typer: latest main branch ( 462d0666b6416416bda00c92124f5d210b3082a4 )
• cds: n/a (using cds-typer's CLI)

Repository Containing a Minimal Reproducible Example

See example above

Anything else?

No response