Keep a move or a delete of chapters that the user makes during a job

A job placed each new chapter with the chapter order from its start, so
a move by hand during the job went back. The store now places a new
chapter against the order that the story has at that moment, in one
transaction. A recheck of a chapter that the user deleted no longer
stops the job.

tests/test_job_races.py

@@ -0,0 +1,92 @@
+"""Changes that the user makes to the chapters of a story while a job runs for it."""
+
+import pytest
+from test_deliver import CHAPTER, linked_story, site, titles, update
+from test_deliver import fake as fake
+from test_deliver import jobs as jobs
+from test_deliver import story_epub as story_epub
+
+from bindery import fff, orchestrator
+from bindery.jobs import DownloadMode
+from bindery.store import Store
+
+THREE = [(1, "One", "a"), (2, "Two", "b"), (3, "Three", "c")]
+
+
+def during_download(monkeypatch, number, action):
+    """Run `action` when the job downloads the chapter with this number."""
+    fetch = fff.fetch_chapter
+
+    def fetch_and_act(adapter, url, index):
+        if url == CHAPTER.format(number):
+            action()
+        return fetch(adapter, url, index)
+
+    monkeypatch.setattr(fff, "fetch_chapter", fetch_and_act)
+
+
+def chapter_id(story_id, title):
+    return next(c["id"] for c in orchestrator.store.list_chapters(story_id) if c["title"] == title)
+
+
+def test_a_move_during_a_download_stays(fake, jobs, monkeypatch):
+    story_id = linked_story(THREE)
+    site(monkeypatch, [*THREE, (4, "Four", "d"), (5, "Five", "e")])
+    during_download(monkeypatch, 4, lambda: orchestrator.move_chapters(story_id, [chapter_id(story_id, "Three")], None))
+    assert "2 new chapters" in update(story_id)
+    assert titles(story_id) == ["Three", "One", "Two", "Four", "Five"]
+
+
+def test_a_new_chapter_in_the_middle_goes_after_its_moved_predecessor(fake, jobs, monkeypatch):
+    story_id = linked_story(THREE)
+    site(monkeypatch, [(1, "One", "a"), (9, "Nine", "x"), (2, "Two", "b"), (3, "Three", "c")])
+    during_download(
+        monkeypatch,
+        9,
+        lambda: orchestrator.move_chapters(story_id, [chapter_id(story_id, "One")], chapter_id(story_id, "Three")),
+    )
+    update(story_id)
+    assert titles(story_id) == ["Two", "Three", "One", "Nine"]
+
+
+def test_a_delete_during_a_download_stays(fake, jobs, monkeypatch):
+    story_id = linked_story(THREE)
+    site(monkeypatch, [*THREE, (4, "Four", "d")])
+    during_download(monkeypatch, 4, lambda: orchestrator.delete_chapters(story_id, [chapter_id(story_id, "Two")]))
+    assert "1 new chapter" in update(story_id)
+    assert titles(story_id) == ["One", "Three", "Four"]
+
+
+def test_a_delete_during_a_recheck_does_not_stop_the_job(fake, jobs, monkeypatch):
+    story_id = linked_story(THREE)
+    site(monkeypatch, [(1, "One", "a2"), (2, "Two", "b2"), (3, "Three", "c2")])
+    during_download(monkeypatch, 2, lambda: orchestrator.delete_chapters(story_id, [chapter_id(story_id, "Two")]))
+    assert "2 of 3 rechecked chapters changed" in update(story_id, DownloadMode.RECHECK_ALL)
+    assert titles(story_id) == ["One", "Three"]
+
+
+def test_the_order_function_of_add_chapters_sees_the_stored_order(tmp_path):
+    store = Store(tmp_path / "db.sqlite")
+    sid = store.create_story("u", "s", "T", "A", [])
+    for n, url in enumerate(["u2", "u1"]):
+        store.add_chapter(sid, url, url, "<p/>", "h", "new", n)
+    new = [{"url": "u3", "title": "u3", "html": "<p/>", "text_hash": "h"}]
+    seen = []
+    store.add_chapters(sid, new, "new", lambda stored: seen.append(stored) or [*stored, "u3"])
+    assert seen == [["u2", "u1"]]
+    assert [c["url"] for c in store.list_chapters(sid)] == ["u2", "u1", "u3"]
+
+
+def test_a_refused_reorder_changes_nothing(tmp_path):
+    store = Store(tmp_path / "db.sqlite")
+    sid = store.create_story("u", "s", "T", "A", [])
+    ids = [store.add_chapter(sid, f"u{n}", str(n), "<p/>", "h", "new", n) for n in range(3)]
+
+    def refuse(order):
+        raise ValueError("no")
+
+    with pytest.raises(ValueError, match="no"):
+        store.reorder_chapters(sid, refuse)
+    assert [c["id"] for c in store.list_chapters(sid)] == ids
+    store.reorder_chapters(sid, lambda order: order[::-1])
+    assert [c["id"] for c in store.list_chapters(sid)] == ids[::-1]

tests/test_store.py

@@ -6,7 +6,7 @@ def test_chapters_revisions_and_rules(tmp_path):
     sid = store.create_story("https://example/s/1", "example", "T", "A", ["title"])
     c1 = store.add_chapter(sid, "u1", "One", "<p>1</p>", "h1", "new", 0)
     c2 = store.add_chapter(sid, "u2", "Two", "<p>2</p>", "h2", "new", 1)
-    store.set_positions(sid, [c2, c1])
+    store.reorder_chapters(sid, lambda order: [c2, c1])
     assert [c["url"] for c in store.chapters_for_build(sid)] == ["u2", "u1"]
 
     assert store.add_revision(c1, "<p>1b</p>", "h1b", "recheck") == 2