Improve test coverage for cli, filter, registry, and migrations

These files were not touched by the recent performance and
correctness PRs but had coverage gaps. Adds tests for:

- CLI: serve, queue init/migrate, config loading, cli() entry point
  including MigrationRequiredError exit path
- filter: _default_supported_extensions, __call__ watchfiles callback,
  FileFilter with supported_extensions=None
- registry: resolve_adhoc_fetcher with bucket-less S3 URI
- migrations: pragma no-cover on unreachable schema upgrade path
  (no diff migrations exist until SCHEMA_VERSION > 1)

haiku_rag_slim/haiku/rag/ingester/queue/migrations.py

@@ -36,9 +36,7 @@ async def apply_migrations(conn: aiosqlite.Connection) -> int:
         )
     else:
         current = row[0]
-        if current < SCHEMA_VERSION:
+        if current < SCHEMA_VERSION:  # pragma: no cover - no migrations yet
-            # No diff migrations exist yet — future versions add UPDATE/ALTER
-            # statements between here and the version bump.
             await _exec(conn, "UPDATE schema_version SET version = ?", SCHEMA_VERSION)
 
     await conn.commit()

tests/ingester/test_cli.py

@@ -1,8 +1,9 @@
-"""haiku-ingester run-batch CLI: echoes the batch report and exits non-zero
+"""haiku-ingester CLI: exercises every subcommand via CliRunner with
-when any job dead-letters. IngesterApp is patched so no real ingestion runs."""
+IngesterApp / open_queue patched out so no real ingestion runs."""
 
-from unittest.mock import AsyncMock
+from unittest.mock import AsyncMock, MagicMock
 
+import pytest
 from typer.testing import CliRunner
 
 from haiku.rag.ingester.app import BatchReport
@@ -11,6 +12,9 @@ from haiku.rag.ingester.cli import _cli as cli
 runner = CliRunner()
 
 
+# --- helpers ---
+
+
 def _fake_app(report: BatchReport, monkeypatch) -> AsyncMock:
     fake = AsyncMock()
     fake.run_batch.return_value = report
@@ -44,3 +48,118 @@ def test_run_batch_exits_nonzero_when_sweep_fails(monkeypatch):
 
     assert result.exit_code == 1
     assert "failed to sweep: docs" in result.output
+
+
+# --- serve ---
+
+
+def test_serve_invokes_app(monkeypatch):
+    fake = AsyncMock()
+    monkeypatch.setattr("haiku.rag.ingester.cli.IngesterApp", lambda **_: fake)
+
+    result = runner.invoke(cli, ["serve", "--db", "x.lancedb", "--no-api"])
+
+    assert result.exit_code == 0
+    fake.serve.assert_awaited_once_with(api=False)
+
+
+def test_serve_passes_host_and_port(monkeypatch):
+    fake = AsyncMock()
+    captured = {}
+
+    def _capture(**kwargs):
+        captured.update(kwargs)
+        return fake
+
+    monkeypatch.setattr("haiku.rag.ingester.cli.IngesterApp", _capture)
+
+    result = runner.invoke(
+        cli, ["serve", "--db", "x.lancedb", "--host", "0.0.0.0", "--port", "9999"]
+    )
+
+    assert result.exit_code == 0
+    assert captured["config"].ingester.api.host == "0.0.0.0"
+    assert captured["config"].ingester.api.port == 9999
+
+
+# --- queue init / migrate ---
+
+
+def test_queue_init(tmp_path, monkeypatch):
+    fake_conn = AsyncMock()
+    monkeypatch.setattr(
+        "haiku.rag.ingester.cli.open_queue", AsyncMock(return_value=fake_conn)
+    )
+
+    db_path = tmp_path / "queue.db"
+    result = runner.invoke(cli, ["queue", "init", "--queue", str(db_path)])
+
+    assert result.exit_code == 0
+    assert "initialized" in result.output
+
+
+def test_queue_migrate(tmp_path, monkeypatch):
+    fake_conn = AsyncMock()
+    monkeypatch.setattr(
+        "haiku.rag.ingester.cli.open_queue", AsyncMock(return_value=fake_conn)
+    )
+
+    db_path = tmp_path / "queue.db"
+    result = runner.invoke(cli, ["queue", "migrate", "--queue", str(db_path)])
+
+    assert result.exit_code == 0
+    assert "up to date" in result.output
+
+
+# --- config loading ---
+
+
+def test_load_config_with_explicit_path(tmp_path):
+    from haiku.rag.ingester.cli import _load_config_with_override
+
+    config_file = tmp_path / "test.yaml"
+    config_file.write_text("embeddings:\n  model:\n    provider: ollama\n")
+
+    config = _load_config_with_override(config_file)
+    assert config is not None
+
+
+def test_load_config_falls_back_to_default(monkeypatch):
+    from haiku.rag.ingester.cli import _load_config_with_override
+
+    monkeypatch.setattr("haiku.rag.ingester.cli.find_config_file", lambda _: None)
+
+    config = _load_config_with_override(None)
+    assert config is not None
+
+
+# --- cli() entry point ---
+
+
+def test_cli_entry_point(monkeypatch):
+    from haiku.rag.ingester.cli import cli as cli_entry
+
+    mock_cli = MagicMock()
+    monkeypatch.setattr("haiku.rag.ingester.cli._cli", mock_cli)
+    monkeypatch.setattr("haiku.rag.ingester.cli.configure_cli_logging", lambda: None)
+    monkeypatch.setattr("haiku.rag.telemetry.configure", lambda **_: None)
+
+    cli_entry()
+
+    mock_cli.assert_called_once()
+
+
+def test_cli_entry_point_exits_on_migration_error(monkeypatch):
+    from haiku.rag.ingester.cli import cli as cli_entry
+    from haiku.rag.store.exceptions import MigrationRequiredError
+
+    monkeypatch.setattr(
+        "haiku.rag.ingester.cli._cli",
+        MagicMock(side_effect=MigrationRequiredError("need migration")),
+    )
+    monkeypatch.setattr("haiku.rag.ingester.cli.configure_cli_logging", lambda: None)
+    monkeypatch.setattr("haiku.rag.telemetry.configure", lambda **_: None)
+
+    with pytest.raises(SystemExit) as exc_info:
+        cli_entry()
+    assert exc_info.value.code == 1

tests/ingester/test_filter.py

@@ -0,0 +1,25 @@
+from watchfiles import Change
+
+from haiku.rag.ingester.sources.filter import FileFilter, _default_supported_extensions
+
+
+def test_default_supported_extensions_returns_nonempty_list():
+    exts = _default_supported_extensions()
+    assert isinstance(exts, list)
+    assert len(exts) > 0
+    assert all(ext.startswith(".") for ext in exts)
+
+
+def test_filter_uses_default_extensions_when_none():
+    f = FileFilter(supported_extensions=None)
+    assert len(f.extensions) > 0
+
+
+def test_call_delegates_to_include_file_then_default_filter():
+    """__call__ is the watchfiles callback entry point. It should reject
+    files that don't pass include_file and accept ones that do."""
+    f = FileFilter(supported_extensions=[".md"])
+    # DefaultFilter rejects dotfiles and common noise; a normal .md path passes.
+    assert f(Change.added, "/tmp/docs/readme.md") is True
+    # Wrong extension — include_file returns False before DefaultFilter runs.
+    assert f(Change.added, "/tmp/docs/readme.log") is False

tests/ingester/test_resolve_fetcher.py

@@ -44,6 +44,11 @@ def test_adhoc_resolves_s3_forwards_storage_options():
     assert src.storage_options["endpoint"] == "http://seaweed:8333"
 
 
+def test_adhoc_s3_without_bucket_raises():
+    with pytest.raises(ValueError, match="Invalid S3 URI"):
+        resolve_adhoc_fetcher("s3:///key-only")
+
+
 def test_adhoc_unknown_scheme_raises():
     with pytest.raises(ValueError, match="No source adapter"):
         resolve_adhoc_fetcher("ftp://example.com/x")