'Ensure headers containing leading whitespace raise
InvalidHeader Error before sending.'

def test_header_no_leading_space(self, httpbin):

    headers_space = {'foo': '    bar'}
    headers_tab = {'foo': '            bar'}
    with pytest.raises(InvalidHeader):
        r = requests.get(httpbin('get'), headers=headers_space)
    with pytest.raises(InvalidHeader):
        r = requests.get(httpbin('get'), headers=headers_tab)
