"""Unit tests for the recursive JSON-safe inspect serializer.""" from __future__ import annotations import asyncio import dataclasses import datetime as dt import enum import json from typing import Any from music_assistant.providers.fastmcp_server.debug.inspect_serializer import _State, dump def test_charge_estimates_bytes_without_json_encoding() -> None: """ ``_State.charge`` sizes values directly, not via ``json.dumps``. For an unescaped string the estimate matches the JSON length (content bytes + 2 quotes). For a string containing a quote, the direct estimate is the UTF-8 length + 2 â strictly less than the JSON-escaped length â which pins that ``json.dumps`` is no longer used. """ state = _State(max_depth=10, max_str=1000, max_total_bytes=1_000_000) state.charge("yyyy") assert state.bytes_used == len(b"yyyy") + 2 quote_state = _State(max_depth=10, max_str=1000, max_total_bytes=1_000_000) quote_state.charge('a"b') assert quote_state.bytes_used == len(b'a"b') + 2 # 5, not json's 6 none_state = _State(max_depth=10, max_str=1000, max_total_bytes=1_000_000) none_state.charge(None) assert none_state.bytes_used == 4 # "null" def test_charge_is_noop_without_budget() -> None: """With no byte budget configured, ``charge`` does nothing.""" state = _State(max_depth=10, max_str=1000, max_total_bytes=None) state.charge("anything") assert state.bytes_used == 0 @dataclasses.dataclass class _Inner: x: int label: str @dataclasses.dataclass class _Outer: name: str inner: _Inner items: list[int] def test_dump_simple_dataclass() -> None: # noqa: D103 obj = _Outer(name="root", inner=_Inner(x=1, label="hi"), items=[1, 2, 3]) out = dump(obj) assert out == {"name": "root", "inner": {"x": 1, "label": "hi"}, "items": [1, 2, 3]} def test_dump_handles_self_reference_without_recursion_error() -> None: # noqa: D103 d: dict[str, Any] = {} d["self"] = d out = dump(d) assert out["self"] == "" def test_dump_max_depth_truncates() -> None: # noqa: D103 deep: dict[str, Any] = {} current = deep for i in range(10): current["next"] = {} current = current["next"] current["leaf"] = "value" out = dump(deep, max_depth=3) def _depth(o: Any, n: int = 0) -> tuple[int, Any]: if isinstance(o, dict) and "next" in o: return _depth(o["next"], n + 1) return n, o depth, leaf = _depth(out) assert depth == 3 assert leaf == "" def test_dump_max_str_truncates_with_suffix() -> None: # noqa: D103 big = "x" * 5000 out = dump(big, max_str=100) assert isinstance(out, str) assert out.startswith("x" * 100) assert "â¦(" in out assert "more chars)" in out class _Color(enum.Enum): RED = "red" BLUE = "blue" def test_dump_enum_to_value() -> None: # noqa: D103 assert dump(_Color.RED) == "red" def test_dump_datetime_to_iso8601() -> None: # noqa: D103 t = dt.datetime(2026, 5, 28, 12, 34, 56, tzinfo=dt.UTC) assert dump(t) == "2026-05-28T12:34:56+00:00" def test_dump_bytes_to_length_placeholder() -> None: # noqa: D103 assert dump(b"\x00" * 4096) == "" def test_dump_unserialisable_objects_render_placeholder() -> None: # noqa: D103 lock = asyncio.Lock() assert dump(lock) == "" def test_dump_property_raising_renders_placeholder() -> None: # noqa: D103 class _Bad: @property def value(self) -> str: raise RuntimeError("not ready") out = dump(_Bad()) assert out["value"] == "" def test_dump_total_payload_cap_marks_truncated() -> None: # noqa: D103 # 300 KB of content (300 strings of 1 KB each); cap at 256 KB. big = {f"k{i}": "y" * 1024 for i in range(300)} out, truncated = dump(big, max_total_bytes=256 * 1024, return_truncated=True) assert truncated is True assert len(json.dumps(out)) <= 256 * 1024 + 1024 # +slack for the marker def test_dump_dataclass_with_raising_property_renders_placeholder() -> None: """ Real-world shape: MA Player is a dataclass with diagnostic @property. The plain-class variant of this test (test_dump_property_raising_renders_placeholder) used a non-dataclass and silently passed even when the dataclass branch did not discover properties â this regression guard pins the actual production case. """ @dataclasses.dataclass class _Broken: player_id: str @property def diagnostic(self) -> str: raise RuntimeError("not ready") out = dump(_Broken(player_id="kitchen")) assert out["player_id"] == "kitchen" assert out["diagnostic"] == "" def test_dump_skips_mass_back_reference_on_dataclasses() -> None: """ ``mass`` field on Player/Queue/Provider is a back-ref to MA's runtime root. Live verification surfaced the regression: walking ``player.mass`` drags the entire MA graph (every other provider, queue, player, cache) into the dump and exhausts the byte budget before the player's own ``player_id``/``name``/ ``current_media`` get serialised â leaving ``raw.keys() == ["mass"]`` with every user-facing field reported as ``null``. The serializer must elide ``mass`` (and the equivalent ``hass`` for Home Assistant) with a transparent placeholder so the caller sees the field exists but the heavy subtree is not chased. """ @dataclasses.dataclass class _Huge: # Stand-in for the MusicAssistant runtime root â a large payload that # would dominate the dump if walked. big: list[int] = dataclasses.field(default_factory=lambda: list(range(10_000))) @dataclasses.dataclass class _Player: player_id: str name: str mass: _Huge hass: _Huge logger: _Huge p = _Player( player_id="kitchen", name="Kitchen", mass=_Huge(), hass=_Huge(), logger=_Huge(), ) out = dump(p) # The user-facing fields ARE present even though they come after the # back-ref in dataclass field order. assert out["player_id"] == "kitchen" assert out["name"] == "Kitchen" # All three back-refs (MA runtime, HA client, scoped Logger) are elided # with a transparent placeholder â the caller sees the field exists but # the heavy subtree was not chased. assert out["mass"] == "" assert out["hass"] == "" assert out["logger"] == "" # And â critically â the 10_000-element ``big`` list inside any of them # did not get walked, so it does not appear anywhere in the payload. assert "big" not in json.dumps(out) def test_dump_dataclass_includes_property_values() -> None: """Dataclass properties whose getters succeed should appear in the output too.""" @dataclasses.dataclass class _Good: x: int @property def doubled(self) -> int: return self.x * 2 out = dump(_Good(x=3)) assert out == {"x": 3, "doubled": 6}

music-assistant-server

music-assistant-server