test_one_currency.py

import csv
import re
import pytest
from urllib.request import Request, urlopen

EXISTING_URL="https://codeforiati.org/imf-exchangerates/imf_exchangerates.csv"

class TestOneCurrency:

    imf_currencies = __import__('imf-currencies')
    country = {
        "@value": "U2",
        "Description": {
        "@xml:lang": "en",
            "#text": "Euro area (Member States and Institutions of the Euro Area) changing composition"
        }
    }
    with open('output/imf_exchangerates_one_currency.csv', 'w') as output_csv:
        writer = csv.DictWriter(output_csv, fieldnames=imf_currencies.FIELDNAMES)
        writer.writeheader()
        imf_currencies.write_data_for_country(writer,
            country=country, sleep_time=0.25, freq='M',
            source='ENDE', target='USD')


    @pytest.fixture
    def countries_currencies(self):
        imf_currencies = __import__('imf-currencies')
        return imf_currencies.countries_currencies


    @pytest.fixture
    def imf_countries(self):
        imf_currencies = __import__('imf-currencies')
        return imf_currencies.imf_countries


    def test_first_row(self):
        """
        Check that the first row outputs the expected data.
        """

        with open("output/imf_exchangerates_one_currency.csv", "r") as input_csv:
            reader = csv.DictReader(input_csv)
            assert next(reader) == {
                'Date': '1999-01-31',
                'Rate': '0.878425860857344',
                'Currency': 'EUR',
                'Frequency': 'M',
                'Source': 'IMF',
                'Country code': 'U2',
                'Country': 'Euro area (Member States and Institutions of the Euro Area) changing composition'
            }

    def test_currency_list(self, countries_currencies):
        """
        Check that there are a lot of countries/currencies listed.
        """

        # At the last count, it was 259. We shouldn't expect it
        # to vary greatly from this.
        assert len(countries_currencies) > 250


    def test_currency_list_contains(self, countries_currencies):
        """
        Check that the list of countries/currencies contains the Eurozone.
        """

        assert "U2" in countries_currencies.keys()


    def test_currency_list_eurozone_countries(self, countries_currencies):
        """
        Check that the list of Eurozone countries/currencies is as expected.
        """
        countries = [k for k, v in countries_currencies.items() if v == 'EUR']
        assert countries == ['AX', 'AD', 'XK', 'MC', 'ME', 'U2']
        # Aland Islands, Andorra, Kosovo, Monaco, Montenegro all use EUR but are not members
        assert len([v for k, v in countries_currencies.items() if v == 'EUR']) == 6