feat(taskflow): add core task API, storage persistence, csv export, stats page, and test coverage

tests/test_repository_persistence.py

@@ -0,0 +1,146 @@
+from __future__ import annotations
+
+from datetime import UTC, datetime, timedelta
+from uuid import uuid4
+
+from app.storage import DATA_FORMAT_VERSION, StoredTask
+from app.storage.repository import JsonFileTaskRepository
+
+
+def make_task(
+    *,
+    title: str = "Task",
+    started: bool = False,
+    done: bool = False,
+) -> StoredTask:
+    now = datetime.now(UTC)
+    started_at = now + timedelta(seconds=1) if started else None
+    done_at = now + timedelta(seconds=2) if done else None
+    return StoredTask(
+        id=uuid4(),
+        title=title,
+        created_at=now,
+        started_at=started_at,
+        done_at=done_at,
+    )
+
+
+def test_replace_all_replaces_empty_state_with_provided_tasks(tmp_path):
+    repo = JsonFileTaskRepository(tmp_path / "tasks.json")
+    task_1 = make_task(title="One")
+    task_2 = make_task(title="Two")
+
+    repo.replace_all([task_1, task_2])
+
+    assert repo.list_tasks() == [task_1, task_2]
+
+
+def test_replace_all_fully_overwrites_previous_content(tmp_path):
+    repo = JsonFileTaskRepository(tmp_path / "tasks.json")
+    old_task = make_task(title="Old")
+    new_task = make_task(title="New")
+    repo.create_task(old_task)
+
+    repo.replace_all([new_task])
+
+    assert repo.list_tasks() == [new_task]
+
+
+def test_data_format_version_matches_constant(tmp_path):
+    repo = JsonFileTaskRepository(tmp_path / "tasks.json")
+
+    assert repo.data_format_version == DATA_FORMAT_VERSION
+
+
+def test_data_format_version_is_stable_across_instances(tmp_path):
+    file_path = tmp_path / "tasks.json"
+
+    repo_1 = JsonFileTaskRepository(file_path)
+    repo_2 = JsonFileTaskRepository(file_path)
+
+    assert repo_1.data_format_version == repo_2.data_format_version == DATA_FORMAT_VERSION
+
+
+def test_missing_file_is_created_automatically(tmp_path):
+    file_path = tmp_path / "nested" / "tasks.json"
+
+    repo = JsonFileTaskRepository(file_path)
+
+    assert repo.list_tasks() == []
+    assert file_path.exists()
+
+
+def test_existing_valid_file_is_loaded_on_new_instance(tmp_path):
+    file_path = tmp_path / "tasks.json"
+    repo_1 = JsonFileTaskRepository(file_path)
+    task = make_task(title="Persisted")
+    repo_1.create_task(task)
+
+    repo_2 = JsonFileTaskRepository(file_path)
+
+    assert repo_2.list_tasks() == [task]
+
+
+def test_parent_directory_is_created_if_missing(tmp_path):
+    file_path = tmp_path / "deep" / "nested" / "data" / "tasks.json"
+
+    repo = JsonFileTaskRepository(file_path)
+
+    assert file_path.parent.exists()
+    assert repo.list_tasks() == []
+
+
+def test_current_version_payload_loads_as_is(tmp_path):
+    file_path = tmp_path / "tasks.json"
+    repo_1 = JsonFileTaskRepository(file_path)
+    task = make_task(title="Versioned")
+    repo_1.create_task(task)
+
+    repo_2 = JsonFileTaskRepository(file_path)
+
+    assert repo_2.data_format_version == DATA_FORMAT_VERSION
+    assert repo_2.list_tasks() == [task]
+
+
+def test_empty_current_version_payload_loads_without_backup(tmp_path):
+    file_path = tmp_path / "tasks.json"
+    repo = JsonFileTaskRepository(file_path)
+
+    assert repo.list_tasks() == []
+    assert not list(tmp_path.glob("tasks.json.corrupted*"))
+
+
+def test_persistence_between_repository_instances(tmp_path):
+    file_path = tmp_path / "tasks.json"
+    repo_1 = JsonFileTaskRepository(file_path)
+    task = make_task(title="Cross-session")
+    repo_1.create_task(task)
+
+    repo_2 = JsonFileTaskRepository(file_path)
+
+    assert repo_2.get_task(task.id) == task
+
+
+def test_multiple_operations_survive_restart(tmp_path):
+    file_path = tmp_path / "tasks.json"
+    repo_1 = JsonFileTaskRepository(file_path)
+
+    task_1 = make_task(title="First")
+    task_2 = make_task(title="Second")
+    repo_1.create_task(task_1)
+    repo_1.create_task(task_2)
+    repo_1.delete_task(task_1.id)
+
+    updated_task_2 = StoredTask(
+        id=task_2.id,
+        title="Second updated",
+        created_at=task_2.created_at,
+        started_at=datetime.now(UTC),
+        done_at=None,
+    )
+    repo_1.update_task(updated_task_2)
+
+    repo_2 = JsonFileTaskRepository(file_path)
+
+    assert repo_2.list_tasks() == [updated_task_2]
+