public async Task UserStreamCloseThrows() { var user = new BinanceApiUser("api-key"); const string listenKey = "listen-key"; await Assert.ThrowsAsync <ArgumentNullException>("user", () => _client.UserStreamCloseAsync((IBinanceApiUser)null, listenKey)); await Assert.ThrowsAsync <ArgumentNullException>("apiKey", () => _client.UserStreamCloseAsync((string)null, listenKey)); await Assert.ThrowsAsync <ArgumentNullException>("listenKey", () => _client.UserStreamCloseAsync(user, null)); await Assert.ThrowsAsync <ArgumentNullException>("listenKey", () => _client.UserStreamCloseAsync(user, string.Empty)); }