from soundchanger.change import is_valid_change
import pytest

def test_valid_change():
    assert is_valid_change('a>b/c_d') == True
    assert is_valid_change('a>b/c__d') == True
    assert is_valid_change('a>b/c_') == True
    assert is_valid_change('a>b/_d') == True
    assert is_valid_change('a>b') == True
    assert is_valid_change('a>b/_') == True
    assert is_valid_change('a>b/') == True

def test_invalid_change():
    assert is_valid_change('>') == False
    assert is_valid_change('>b') == False
    assert is_valid_change('a>b/a') == False
    assert is_valid_change('>/_') == False
    assert is_valid_change('a>b//c_d') == False

def test_raises_value_error():
    with pytest.raises(ValueError):
        is_valid_change('>', ignore_errors=False)
    with pytest.raises(ValueError):
        is_valid_change('>', ignore_errors=False)
    with pytest.raises(ValueError):
        is_valid_change('>b', ignore_errors=False)
    with pytest.raises(ValueError):
        is_valid_change('a>b/a', ignore_errors=False)
    with pytest.raises(ValueError):
        is_valid_change('>/_', ignore_errors=False)
    with pytest.raises(ValueError):
        is_valid_change('a>b//c_d', ignore_errors=False)