[BUG][Typescript] Invalid type for the enum array

[wtrocki]

Bug Report Checklist

• Have you provided a full/minimal spec to reproduce the issue?
• Have you validated the input using an OpenAPI validator (example)?
• Have you tested with the latest master to confirm the issue still exists?
• Have you searched for related issues/PRs?
• What's the actual output vs expected output?
• [Optional] Sponsorship to speed up the bug fix or feature request (example)

Description

Array of enums causes compilation error:

        index:
          type: array
          items:
              type: string
              enum:
                - "1"
                - "1"
                - "-1"

error:

public property ''index'' of exported class has or is using private name 'InnerEnum'.

31     'index'?: Array<{ [key: InnerEnum]: InnerEnum; }>;

openapi-generator version

both master and latest release.

OpenAPI declaration file content or url

Generation Details

Generator typescript.

Steps to reproduce

Run generator for schema above.

Related issues/PRs

Suggest a fix

datatypeWithEnum is not set properly in model:
https://github.com/OpenAPITools/openapi-generator/blob/master/modules/openapi-generator/src/main/resources/typescript/model/model.mustache#L22

[wtrocki]

@macjohnny - It looks the generator no longer can generate inline enums and it fails to reference them.
If you have any suggestion on how to fix this I'm happy to contribute that change.

[macjohnny]

@TiFu any suggestion?

[TiFu]

@wtrocki Can you share a sample/simplified OAI spec to reproduce this?

Happy to look into this next weekend and figure out how to fix it. Don't have a concrete idea how to fix it without digging in a bit and reproducing the issue.

[wtrocki]

I had seen this problem when playing with Atlas OpenAPI: https://github.com/wtrocki/ts-client-atlas/blob/main/openapi/atlas-api-transformed.yaml

[TiFu]

Thanks!

I started looking into this on the weekend and it looks a bit more complicated to truly fix the underlying issue.

The problem is that we try to retroactively fix the type for maps (i.e., in OpenAPI spec parlance object with additionalProperties:

• We first generate { [key: string]: string } in your example
• This is then later "fixed" with a string replace from { [key]: string: string } to { [key: InnerEnum]: InnerEnum } - this is obviously incorrect given that this should remain { [key: string]: InnerEnum }

[wtrocki]

@TiFu - While not perfect solution for this issue I think that second stage could be controlled by config value.
To make it clear - other generators like golang tend to ignore enums that are defined in such a way (return string or map in this case). My take is that if we were to introduce config value like:

TypeSafeEnumMaps (default true) or something like this users can decide to skip enum mappings globally.

This is in fact how I made this work in the first place without understanding low-level issues related to that problem.
I found mapping logic around enums quite complex so if we can intentionally disable it it will be nice side measure for more complex line of work. Happy to PR with the fix on weekend.

[TiFu]

I would be fine with this as a work-around for now.

The long-term solution should however be that we fix how we generate types. It should be a simple fix if we change the method where we generate the datatype string initially. Hopefully find some time during the public holidays this week to have a deeper look whether there's a simple fix.

[1] export type ApiPerformanceAdvisorIndexViewIndexEnum = "1" | "1" | "-1" ;