Summary

• Fixes the misleading --run-time limit reached log message that appears when a LoadTestShape test completes naturally or is interrupted, even though the stop was not caused by the --run-time limit.
• Adds a reason parameter to stop_and_optionally_quit() (defaults to "--run-time limit reached" for backward compatibility) and passes "Shape test completed" from the shape class finally block.
• Updates corresponding tests to expect the corrected log message.

Fixes #3178

Context

As noted in #3178, calling stop() / quit() or letting a LoadTestShape finish naturally would print --run-time limit reached, shutting down (or stopping test), which is incorrect and confusing since the stop was not triggered by --run-time. A maintainer acknowledged this as a valid bug but it was closed as stale with no fix applied.

Changes

• locust/main.py: stop_and_optionally_quit() now takes an optional reason parameter. The timer-based call (spawn_run_time_quit_greenlet) still passes the default "--run-time limit reached". The shape class finally block now passes "Shape test completed".
• locust/test/test_main.py: Updated two shape-class integration tests (test_autostart_w_load_shape and test_autostart_multiple_locustfiles_with_shape) to expect "Shape test completed" instead of "--run-time limit reached".

Test plan

• Existing tests in test_main.py and test_log.py that verify --run-time limit reached for actual timer-triggered stops remain unchanged and should pass
• The two updated shape-class tests should now correctly expect "Shape test completed"
• Manual test: run a LoadTestShape with --autostart and verify the log says "Shape test completed, stopping test" instead of "--run-time limit reached, stopping test"