"""Timezone detection tests."""
import sys
from pathlib import Path

sys.path.insert(0, str(Path(__file__).parent.parent / "src"))

from fenris import tz_util


def test_relative_localtime_symlink_returns_zoneinfo_key(tmp_path, monkeypatch):
    zoneinfo = tmp_path / "usr" / "share" / "zoneinfo" / "Asia" / "Kolkata"
    zoneinfo.parent.mkdir(parents=True)
    zoneinfo.write_bytes(b"zoneinfo")
    localtime = tmp_path / "etc" / "localtime"
    localtime.parent.mkdir()
    localtime.symlink_to("../usr/share/zoneinfo/Asia/Kolkata")

    real_path = tz_util.Path
    monkeypatch.setattr(
        tz_util,
        "Path",
        lambda path: localtime if path == "/etc/localtime" else real_path(path),
    )
    monkeypatch.delenv("TZ", raising=False)

    assert tz_util.detect_system_tz() == "Asia/Kolkata"