test(downloads): cover preferred naming hint propagation in get_or_download

tests/downloads/test_download_manager_workflow.py

@@ -1,6 +1,7 @@
 from __future__ import annotations
 
 from pathlib import Path
+from typing import Any, cast
 
 import pytest
 
@@ -14,9 +15,14 @@ def _bare_manager(tmp_path: Path) -> DownloadManager:
     manager = DownloadManager.__new__(DownloadManager)
     manager.cache_dir = tmp_path
     manager.chunk_size = 1024
-    manager.auth = type(
+    manager.auth = cast(
-        "Auth", (), {"adp_token": "x", "locale": type("Loc", (), {"domain": "fr"})()}
+        Any,
-    )()
+        type(
+            "Auth",
+            (),
+            {"adp_token": "x", "locale": type("Loc", (), {"domain": "fr"})()},
+        )(),
+    )
     return manager
 
 
@@ -48,8 +54,12 @@ def test_get_or_download_uses_cached_file_when_available(
 ) -> None:
     """Ensure cached files bypass link generation and download work."""
     manager = _bare_manager(tmp_path)
-    monkeypatch.setattr(manager, "_get_name_from_asin", lambda asin: "Book")
+    monkeypatch.setattr(
-    cached_path = tmp_path / "Book.aax"
+        manager,
+        "_get_filename_stems_from_asin",
+        lambda asin, preferred_title=None, preferred_author=None: ["Author_Book"],
+    )
+    cached_path = tmp_path / "Author_Book.aax"
     cached_path.write_bytes(b"1" * MIN_FILE_SIZE)
     messages: list[str] = []
     assert manager.get_or_download("ASIN", notify=messages.append) == cached_path
@@ -61,7 +71,11 @@ def test_get_or_download_reports_invalid_url(
 ) -> None:
     """Ensure workflow reports invalid download URLs and aborts."""
     manager = _bare_manager(tmp_path)
-    monkeypatch.setattr(manager, "_get_name_from_asin", lambda asin: "Book")
+    monkeypatch.setattr(
+        manager,
+        "_get_filename_stems_from_asin",
+        lambda asin, preferred_title=None, preferred_author=None: ["Author_Book"],
+    )
     monkeypatch.setattr(
         manager, "_get_download_link", lambda asin, notify=None: "ftp://bad"
     )
@@ -75,7 +89,11 @@ def test_get_or_download_handles_download_failure(
 ) -> None:
     """Ensure workflow reports failures when stream download does not complete."""
     manager = _bare_manager(tmp_path)
-    monkeypatch.setattr(manager, "_get_name_from_asin", lambda asin: "Book")
+    monkeypatch.setattr(
+        manager,
+        "_get_filename_stems_from_asin",
+        lambda asin, preferred_title=None, preferred_author=None: ["Author_Book"],
+    )
     monkeypatch.setattr(
         manager, "_get_download_link", lambda asin, notify=None: "https://ok"
     )
@@ -83,3 +101,30 @@ def test_get_or_download_handles_download_failure(
     messages: list[str] = []
     assert manager.get_or_download("ASIN", notify=messages.append) is None
     assert "Download failed" in messages
+
+
+def test_get_or_download_uses_preferred_naming_hints(
+    tmp_path: Path, monkeypatch: pytest.MonkeyPatch
+) -> None:
+    """Ensure preferred title/author are forwarded to filename stem selection."""
+    manager = _bare_manager(tmp_path)
+    captured: list[tuple[str | None, str | None]] = []
+
+    def stems(
+        asin: str,
+        preferred_title: str | None = None,
+        preferred_author: str | None = None,
+    ) -> list[str]:
+        """Capture naming hints and return one deterministic filename stem."""
+        del asin
+        captured.append((preferred_title, preferred_author))
+        return ["Author_Book"]
+
+    monkeypatch.setattr(manager, "_get_filename_stems_from_asin", stems)
+    monkeypatch.setattr(manager, "_get_download_link", lambda asin, notify=None: None)
+    manager.get_or_download(
+        "ASIN",
+        preferred_title="11/22/63",
+        preferred_author="Stephen King",
+    )
+    assert captured == [("11/22/63", "Stephen King")]