"""Envelope tests for cat-object command."""
from __future__ import annotations
from collections.abc import Mapping
import json
import pytest
from tests.cli_test_helper import CliRunner

runner = CliRunner()

_FIELDS = ("muse_version", "schema", "timestamp", "warnings")


def _check(d: Mapping[str, object]) -> None:
    for f in _FIELDS:
        assert f in d, f"missing {f}"
    assert "schema_version" not in d


class TestCatObjectEnvelope:
    def test_cat_object_info_has_envelope(self) -> None:
        # Get a real object ID from the repo
        r = runner.invoke(None, ["ls-files", "--json"])
        assert r.exit_code == 0, r.output
        files = json.loads(r.output)["files"]
        assert files, "need at least one tracked file"
        obj_id = files[0]["object_id"]
        r2 = runner.invoke(None, ["cat-object", obj_id, "--json"])
        assert r2.exit_code == 0, r2.output
        _check(json.loads(r2.output))