"""Unit tests for the unit_lookup function."""

import copd
import pandas as pd


def test_unit_lookup_defined():
    """Test unit lookup output for all defined unit codes."""
    assert copd.unit_lookup(pd.Series(0)) == 'Count'
    assert copd.unit_lookup(pd.Series(1)) == 'CountPerSecond'
    assert copd.unit_lookup(pd.Series(2)) == 'InternationalUnit'
    assert copd.unit_lookup(pd.Series(3)) == 'Joule'
    assert copd.unit_lookup(pd.Series(4)) == 'Kelvin'
    assert copd.unit_lookup(pd.Series(5)) == 'Kilogram'
    assert copd.unit_lookup(pd.Series(6)) == 'KilogramPerLiter'
    assert copd.unit_lookup(pd.Series(7)) == 'KilogramPerSquareMeter'
    assert copd.unit_lookup(pd.Series(8)) == 'Liter'
    assert copd.unit_lookup(pd.Series(9)) == 'LiterPerKilogramSecond'
    assert copd.unit_lookup(pd.Series(10)) == 'LiterPerSecond'
    assert copd.unit_lookup(pd.Series(11)) == 'Meter'
    assert copd.unit_lookup(pd.Series(12)) == 'Pascal'
    assert copd.unit_lookup(pd.Series(13)) == 'Percent'
    assert copd.unit_lookup(pd.Series(14)) == 'Second'
    assert copd.unit_lookup(pd.Series(15)) == 'Siemen'


def test_unit_lookup_undefined():
    """Test unit lookup output for undefined unit code and other input."""
    assert copd.unit_lookup(pd.Series(16)) == 'Undefined'
    assert copd.unit_lookup(pd.Series(42)) == 'Undefined'
    assert copd.unit_lookup(pd.Series('A')) == 'Undefined'