Use Single instead of First
MODIFY
MagicalCryptoWallet.Tests/RegTests.cs
MagicalCryptoWallet.Tests/RegTests.cs
@@ -485,7 +485,7 @@ namespace MagicalCryptoWallet.Tests
Assert.NotEmpty(firstCoin.SpentOutputs);
Assert.Equal(txid, firstCoin.TransactionId);
Assert.Single(keyManager.GetKeys(KeyState.Used, false));
- Assert.Equal("foo Label", keyManager.GetKeys(KeyState.Used, false).First().Label);
+ Assert.Equal("foo Label", keyManager.GetKeys(KeyState.Used, false).Single().Label);
// Get some money, make it confirm.
key = wallet.GetReceiveKey("");

Use Single instead of First