config = config_from(os.devnull)

    assert not config.get_loaders().loaders

@pytest.mark.parametrize('ini_filename,expected_currency,use_switch', [

    (os.devnull, 'USD', False),

    ('full.ini', 'INI', False),

    ('full.ini', 'EUR', True),

])

def test_historical_default_base(ini_filename, expected_currency, use_switch, any_date):

    arglist = ['historical']

    if use_switch:

        arglist.extend(['--base', expected_currency])

    arglist.append(any_date.isoformat())

    config = config_from(ini_filename, arglist)

    assert config.args.base == expected_currency

@pytest.mark.parametrize('amount,from_curr,preposition,to_curr', [

    (None, 'JPY', None, None),

    (None, 'gbp', None, 'Aud'),

    (None, 'CHF', 'to', 'eur'),

    (decimal.Decimal('1000'), 'chf', None, None),

    (decimal.Decimal('999'), 'Eur', None, 'Chf'),

    (decimal.Decimal('12.34'), 'gbp', 'IN', 'eur'),

])

def test_historical_argparsing_success(amount, from_curr, preposition, to_curr, any_date):

    oxrlib.config.Configuration.TODAY = datetime.date(2017, 1, 1)

    # This locale's currency should not be used in any test cases above.

    oxrlib.config.Configuration.LOCALE = babel.core.Locale('en', 'IN')

    arglist = ['historical', any_date.isoformat()]

    arglist.extend(str(s) for s in [amount, from_curr, preposition, to_curr]

                   if s is not None)

    config = config_from(os.devnull, arglist)

    expect_to_curr = 'INR' if to_curr is None else to_curr.upper()

    assert config.args.amount == amount

    assert config.args.from_currency == from_curr.upper()

    assert config.args.to_currency == expect_to_curr

@pytest.mark.parametrize('arglist', [

    ['100'],

    ['120', 'dollars'],

    ['to', '42', 'usd'],

    ['99', 'usd', 'minus', 'jpy'],

    ['usdjpy'],

    ['44', 'eur', 'in', 'chf', 'pronto'],

    ['eur', 'into'],

    ['50', 'jpy', 'in'],

])

def test_historical_argparsing_failure(arglist, any_date):

    arglist = ['historical', any_date.isoformat()] + arglist

    try:

        config = config_from(os.devnull, arglist)

    except SystemExit:

        pass

    else:

        assert not vars(config.args), "bad arglist succeeded"

@pytest.mark.parametrize('date_s,expect_year,expect_month,expect_day', [

    ('5', 1965, 7, 5),

    ('05', 1965, 7, 5),

    ('14', 1965, 7, 14),

    ('15', 1965, 7, 15),

    ('16', 1965, 6, 16),

    ('3-6', 1965, 3, 6),

    ('11.10', 1964, 11, 10),

    ('07-14', 1965, 7, 14),

    ('07/15', 1965, 7, 15),

    ('7.16', 1964, 7, 16),

    ('917/12/12', 917, 12, 12),

    ('2017-11-1', 2017, 11, 1),

])

def test_good_date_parsing(date_s, expect_year, expect_month, expect_day):

    oxrlib.config.Configuration.TODAY = datetime.date(1965, 7, 15)

    config = config_from(os.devnull, ['historical', date_s])

    actual_date = config.args.date

    assert actual_date.year == expect_year

    assert actual_date.month == expect_month

    assert actual_date.day == expect_day

@pytest.mark.parametrize('date_s', [

    '99',

    '8-88',

    '77-7',

    '0xf-1-2',

    '0b1-3-4',

    '2017/5.9',

    '2018-6/10',

    '1-2-3-4',

    '12/11/10',

])

def test_bad_date_parsing(date_s):

    try:

        config = config_from(os.devnull, ['historical', date_s])

    except SystemExit:

        pass

    else:

        assert not config.args.date, "date parsed from {!r}".format(date_s)