US05-06: Automate Phase E End-to-End Acceptance (#76)

tests/integration/test_worker.py

@@ -90,6 +90,26 @@ def test_cooperative_cancellation_leaves_items_resumable(sf, jobs):
     assert by_state.get(ItemState.QUEUED) == 1  # "b" left resumable
 
 
+def test_a_handler_that_stops_itself_releases_the_lock(sf, jobs):
+    """A handler may stop without anyone cancelling the *job* — an upload batch
+    cancelled through its own API does exactly that. The job is still ``running``
+    when it raises, so it has to reach ``cancelled`` through ``cancelling``; if that
+    hop is skipped the transition is rejected and the lock is held forever."""
+    from photo_pipeline.jobs.handlers import Cancelled
+
+    def handler(item, ctx):
+        raise Cancelled("the work this job wraps was stopped elsewhere")
+
+    worker = Worker(sf, {"scan": handler}, "w1")
+    job = jobs.enqueue("scan", lock="library_write", items=["a"])
+    worker.run_once()
+
+    assert jobs.get(job["id"])["state"] == JobState.CANCELLED
+    assert jobs.progress(job["id"])["by_state"] == {ItemState.QUEUED: 1}  # resumable
+    # The lane is free: the next job may be enqueued under the same lock.
+    assert jobs.enqueue("scan", lock="library_write", items=["b"])["state"] == JobState.QUEUED
+
+
 def test_fencing_rejects_superseded_worker(sf, jobs):
     job = jobs.enqueue("scan", items=["a"])
     stale = jobs.claim(["scan"], "old")