AsyncOAuthFlow raises UnboundLocalError on org-wide install without a bot token #1596

Reproducible in:

The slack_bolt version

slack_bolt==1.30.0
slack_sdk==3.45.0

Python runtime version

Python 3.12.5

OS info

macOS 27.0

Steps to reproduce:

Use AsyncApp with OAuth and have an Enterprise Grid org install the app with only user scopes (no bot scopes). The oauth.v2.access response then has no access_token for the bot and is_enterprise_install is true.

1. Configure AsyncOAuthFlow with user scopes only.
2. Install the app at the organization level (org-wide install).
3. Complete the OAuth redirect.

Expected result:

The installation is saved and the redirect succeeds, the same as it does with the sync OAuthFlow.

Actual result:

AsyncOAuthFlow.run_installation in slack_bolt/oauth/async_oauth_flow.py raises:

UnboundLocalError: cannot access local variable 'auth_test' where it is not associated with a value

The code reads auth_test.get("url") for enterprise installs, but auth_test is only set when a bot token exists. The sync OAuthFlow.run_installation nests that line inside the if bot_token is not None: block, so the two have drifted apart.

I have a fix that mirrors the sync version, with tests for both, in #1590.

Requirements

I have read the Contributing guidelines and Code of Conduct.