refactor: 推进后端分层架构治理

tests/test_history_mutation_command.py

@@ -0,0 +1,123 @@
+from types import SimpleNamespace
+from unittest.mock import Mock
+
+import pytest
+
+from app.application.history import (
+    DownloadHistoryMutationCommand,
+    TransferHistoryMutationCommand,
+)
+
+
+def _transfer_command(*, history=None, delete_result=True, commit_error=None):
+    """构造可观察整理历史事务和外部副作用的命令。"""
+    repository = Mock()
+    repository.get.return_value = history
+    download_repository = Mock()
+    unit_of_work = Mock()
+    unit_of_work.commit.side_effect = commit_error
+    dependencies = {
+        "repository": repository,
+        "download_repository": download_repository,
+        "unit_of_work": unit_of_work,
+        "file_item_factory": lambda payload: SimpleNamespace(**payload),
+        "delete_media_file": Mock(return_value=delete_result),
+        "publish_download_file_deleted": Mock(),
+        "clear_failures": Mock(),
+    }
+    return TransferHistoryMutationCommand(**dependencies), dependencies
+
+
+def _history():
+    """构造包含源和目标文件信息的整理历史快照。"""
+    return SimpleNamespace(
+        id=7,
+        src="/downloads/demo.mkv",
+        src_storage="local",
+        download_hash="abc",
+        src_fileitem={"path": "/downloads/demo.mkv"},
+        dest_fileitem={"path": "/media/demo.mkv"},
+    )
+
+
+def test_download_history_delete_rolls_back_commit_failure():
+    """下载历史提交失败时必须回滚请求级事务。"""
+    repository = Mock()
+    unit_of_work = Mock()
+    unit_of_work.commit.side_effect = RuntimeError("commit failed")
+    command = DownloadHistoryMutationCommand(
+        repository=repository,
+        unit_of_work=unit_of_work,
+    )
+
+    with pytest.raises(RuntimeError, match="commit failed"):
+        command.delete(8)
+
+    repository.stage_delete_history.assert_called_once_with(8)
+    unit_of_work.rollback.assert_called_once_with()
+
+
+def test_transfer_source_delete_failure_keeps_database_unchanged():
+    """源文件删除失败时不得删除历史或更新下载文件状态。"""
+    command, dependencies = _transfer_command(
+        history=_history(),
+        delete_result=False,
+    )
+
+    result = command.delete(7, delete_source=True)
+
+    assert result.success is False
+    assert result.message == "/downloads/demo.mkv 删除失败"
+    dependencies["repository"].stage_delete.assert_not_called()
+    dependencies["download_repository"].stage_delete_file_by_fullpath.assert_not_called()
+    dependencies["unit_of_work"].commit.assert_not_called()
+
+
+def test_transfer_delete_commits_before_event_and_retry_cleanup():
+    """整理记录提交成功后才发送文件删除事件并清理失败计数。"""
+    calls = []
+    command, dependencies = _transfer_command(history=_history())
+    dependencies["unit_of_work"].commit.side_effect = lambda: calls.append("commit")
+    dependencies["publish_download_file_deleted"].side_effect = (
+        lambda _payload: calls.append("event")
+    )
+    dependencies["clear_failures"].side_effect = lambda *_args: calls.append("clear")
+
+    result = command.delete(
+        7,
+        delete_source=True,
+        delete_destination=True,
+    )
+
+    assert result.success is True
+    dependencies["download_repository"].stage_delete_file_by_fullpath.assert_called_once_with(
+        "/downloads/demo.mkv"
+    )
+    dependencies["repository"].stage_delete.assert_called_once_with(7)
+    assert calls == ["commit", "event", "clear"]
+
+
+def test_transfer_commit_failure_suppresses_event_and_retry_cleanup():
+    """数据库提交失败时不得发布已删除事件或清除重试状态。"""
+    command, dependencies = _transfer_command(
+        history=_history(),
+        commit_error=RuntimeError("commit failed"),
+    )
+
+    with pytest.raises(RuntimeError, match="commit failed"):
+        command.delete(7, delete_source=True)
+
+    dependencies["unit_of_work"].rollback.assert_called_once_with()
+    dependencies["publish_download_file_deleted"].assert_not_called()
+    dependencies["clear_failures"].assert_not_called()
+
+
+def test_transfer_truncate_uses_single_transaction():
+    """清空整理历史只暂存一次并统一提交。"""
+    command, dependencies = _transfer_command()
+
+    result = command.truncate()
+
+    assert result.success is True
+    dependencies["repository"].stage_truncate.assert_called_once_with()
+    dependencies["unit_of_work"].commit.assert_called_once_with()