[BUG] [PYTHON] [FAST API] Given supportingFiles-false, APIs still use a not-generated `extra_modules.py`

[urmichm]

Bug Report Checklist

• Have you provided a full/minimal spec to reproduce the issue?
• Have you validated the input using an OpenAPI validator?
• 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?
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Description

When setting "supportingFiles" to "false", generated APIs still look for unused and not-generated extra_modules.py

from <SERVICE_NAME>.models.extra_models import TokenModel # noqa: F401

openapi-generator version

7.x

[KannaKim]

Hi, thanks for reporting the issue. Let me just quickly drop reproduction step here.

Reproduction steps

1. Build the CLI from the latest master:

./mvnw -pl modules/openapi-generator-cli -am -DskipTests package

2. Create an unauthenticated OpenAPI specification named issue_23008.yaml:

openapi: 3.0.3
info:
 title: Supporting-files reproduction
 version: 1.0.0
paths:
 /pets:
 get:
 operationId: listPets
 responses:
 "200":
 description: A list of pets
 content:
 application/json:
 schema:
 type: array
 items:
 $ref: "#/components/schemas/Pet"
components:
 schemas:
 Pet:
 type: object
 required:
 - name
 properties:
 name:
 type: string

3. Generate only APIs and models, excluding supporting files:

java -jar modules/openapi-generator-cli/target/openapi-generator-cli.jar generate \
 -g python-fastapi \
 -i issue_23008.yaml \
 -o out/issue_23008 \
 --additional-properties packageName=issue_23008_api \
 --global-property apis,models

4. Then you will see extra_models.py was not generated
5. However in default_api.py, it still imports from extra_models.py
from issue_23008_api.models.extra_models import TokenModel # noqa: F401