fix(typescript-nestjs-server): import generic return types

[zonradkuse]

We observed that Array return types would be missing their corresponding import in the controller and the api. The cause is a typo in the typescript-nestjs-server generator that checked if a full Array type needed importing instead of the generic parameter T to Array<T>.

This PR fixes the behaviour.

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---

Summary by cubic

Fixes missing imports for generic return types in the typescript-nestjs-server generator by importing the generic type (e.g., T in Array) instead of the container type. This ensures controllers and APIs include correct model imports and avoids compile errors.

^{Written for commit 95e899a. Summary will update on new commits.}

[cubic-dev-ai]

No issues found across 1 file

_{Re-trigger cubic}

[wing328]

Thanks for the PR but your commit (as shown in the Commits tab) is not linked to your Github account, which means this PR won't count as your contribution in https://github.com/OpenAPITools/openapi-generator/graphs/contributors.

Let me know if you need help fixing it.

Ref: https://github.com/OpenAPITools/openapi-generator/wiki/FAQ#how-can-i-update-commits-that-are-not-linked-to-my-github-account

[zonradkuse]

Fixed. Thanks for noticing.

[wing328]

cc @aryobenholzner (author of the generator)

[wing328]

@zonradkuse do you mind sharing a minimal spec to reproduce the issue?

[zonradkuse]

Sure:

openapi: 3.1.0
info:
 title: test
 version: 0.0.0
paths:
    /users:
      get:
        operationId: getUsers
        responses:
          '200':
            description: OK
            content:
              application/json:
                schema:
                  type: array
                  items:
                    $ref: '#/components/schemas/User'

components:
  schemas:
    User:
      type: object
      properties:
        id:
          type: string

then npx @openapitools/openapi-generator-cli generate -i openapi-test.yml -g typescript-nestjs-server -o nest.

Then have a look at the imports in controllers/DefaultApi.controller.ts.

[aryobenholzner]

can verify the issue and the fix.

the existing tests didn't pick this one up, because petstore.yaml uses the generic return types in more places.

maybe there's an existing sample we could add to the test suite? but not sure if that's necessary and/or feasible