How to use the blacksheep.url.URL function in blacksheep

def test_cannot_concatenate_absolute_urls():
    with pytest.raises(ValueError):
        URL(b'https://world-cats.eu') + URL(b'https://hello-world')

    with pytest.raises(ValueError):
        URL(b'http://world-cats.eu') + URL(b'http://hello-world')

def test_relative_url():
    url = URL(b'/api/cat/001?foo=power&hello=world')

    assert url.path == b'/api/cat/001'
    assert url.schema is None
    assert url.host is None
    assert url.port == 0
    assert url.query == b'foo=power&hello=world'
    assert url.fragment is None
    assert url.is_absolute is False

def test_base_url(value, expected_base_url):
    url = URL(value)
    base_url = url.base_url()
    assert expected_base_url == base_url.value

def test_cannot_concatenate_absolute_urls():
    with pytest.raises(ValueError):
        URL(b'https://world-cats.eu') + URL(b'https://hello-world')

    with pytest.raises(ValueError):
        URL(b'http://world-cats.eu') + URL(b'http://hello-world')

def test_concatenation():
    assert URL(b'') + URL(b'') == URL(b'')
    assert URL(b'https://world-cats.eu') + URL(b'/api/cats') == URL(b'https://world-cats.eu/api/cats')
    assert URL(b'https://world-cats.eu/') + URL(b'/api/cats') == URL(b'https://world-cats.eu/api/cats')

def test_equality():
    assert URL(b'') == URL(b'')
    assert URL(b'/api/cats') == URL(b'/api/cats')
    assert URL(b'/api/cats') != URL(b'/api/cat/001')

def test_cannot_concatenate_one_url_first_with_query_or_path():
    with pytest.raises(ValueError):
        URL(b'https://world-cats.eu?hello=world') + URL(b'/api/cats')

    with pytest.raises(ValueError):
        URL(b'http://world-cats.eu/#/about') + URL(b'/api/cats')

def test_empty_url():
    url = URL(b'')

    assert url.path is None
    assert url.schema is None
    assert url.host is None
    assert url.port == 0
    assert url.query is None
    assert url.fragment is None
    assert url.is_absolute is False

def test_cannot_concatenate_one_url_first_with_query_or_path():
    with pytest.raises(ValueError):
        URL(b'https://world-cats.eu?hello=world') + URL(b'/api/cats')

    with pytest.raises(ValueError):
        URL(b'http://world-cats.eu/#/about') + URL(b'/api/cats')

def test_request_can_update_url(initial_url, new_url):
    request = Request('GET', initial_url, None)

    assert request.url.value == initial_url

    request.url = URL(new_url)

    assert request.url.value == new_url