feat: better shutdowns

tests/core/test_shutdown_flag.py

@@ -0,0 +1,37 @@
+"""Unit tests for the process-wide graceful-shutdown flag."""
+
+import pytest
+
+from application.core import shutdown
+
+
+@pytest.fixture(autouse=True)
+def _reset_flag():
+    shutdown.reset_shutdown()
+    yield
+    shutdown.reset_shutdown()
+
+
+@pytest.mark.unit
+def test_flag_starts_clear():
+    assert shutdown.is_shutting_down() is False
+
+
+@pytest.mark.unit
+def test_begin_shutdown_sets_flag():
+    shutdown.begin_shutdown()
+    assert shutdown.is_shutting_down() is True
+
+
+@pytest.mark.unit
+def test_begin_shutdown_is_idempotent():
+    shutdown.begin_shutdown()
+    shutdown.begin_shutdown()
+    assert shutdown.is_shutting_down() is True
+
+
+@pytest.mark.unit
+def test_reset_clears_flag():
+    shutdown.begin_shutdown()
+    shutdown.reset_shutdown()
+    assert shutdown.is_shutting_down() is False