public async Task ThrowArgumentNullException_WhenNullParametersPassed()
{
// Arrange
var sut = new ExchangeRatesApiCaller();
//Act && Assert
await Assert.ThrowsExceptionAsync <ArgumentNullException>(async() => await sut.GetCurrenciesRatesAsync(null, null));
}
public async Task ReturnUnavalibleMessage_WhenInvalidParametersPassed()
{
// Arrange
var sut = new ExchangeRatesApiCaller();
//Act
var result = await sut.GetCurrenciesRatesAsync("https://apiurl.io", "parameters");
StringAssert.Contains(result, "not available");
}