Incorrect fallback logic

[rjgoyln]

Description

When AIRFLOW_CLI_DEBUG_MODE is set to true, if the primary config file exists but the debug_credentials file is missing, the system incorrectly reports "No credentials file found" instead of the expected debug-specific error.

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[bugraoz93]

Looks good! Thanks for the PR! I have a small nit with a comment in test else looks good. After that amendment, would be happy to approve

[Copilot]

Pull request overview

Fixes incorrect error reporting when AIRFLOW_CLI_DEBUG_MODE=true and the main CLI config exists but the debug credentials file is missing, ensuring a debug-specific “missing debug credentials” error is raised instead of the generic “No credentials file found”.

Changes:

• Catch missing debug credentials file separately during Credentials.load() and raise a debug-specific AirflowCtlCredentialNotFoundException.
• Add a regression test covering the “config present + debug creds missing” scenario in debug mode.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

File	Description
airflow-ctl/src/airflowctl/api/client.py	Adds targeted FileNotFoundError handling for missing debug credentials to avoid falling into the generic “no credentials file” path.
airflow-ctl/tests/airflow_ctl/api/test_client.py	Adds a regression test asserting the correct exception/message when debug creds are missing but the primary config exists.