Don't create two similar outputs, when funding transactions

dexX7 · dexX7 · commit b0c837c9e972 · 2018-09-11T09:49:25.000+02:00
When specifying a similar destination for the recipient of the transaction and source to pay the fees with, the builder would create a transaction with two similar outputs. This is combined into one with this change.
diff --git a/src/omnicore/wallettxbuilder.cpp b/src/omnicore/wallettxbuilder.cpp
@@ -203,7 +203,7 @@ int CreateFundedTransaction(
     }
 
     // add reference output, if there is one
-    if (!receiverAddress.empty()) {
+    if (!receiverAddress.empty() && receiverAddress != feeAddress) {
         CScript scriptPubKey = GetScriptForDestination(CBitcoinAddress(receiverAddress).Get());
         vecSend.push_back(std::make_pair(scriptPubKey, GetDustThreshold(scriptPubKey)));
     }
@@ -232,7 +232,7 @@ int CreateFundedTransaction(
         PrintToLog("%s: ERROR: sender %s has no coins\n", __func__, senderAddress);
         return MP_INPUTS_INVALID;
     }
-    
+
     // prepare sources for fees
     std::set<CTxDestination> feeSources;
     feeSources.insert(CBitcoinAddress(feeAddress).Get());
@@ -244,6 +244,11 @@ int CreateFundedTransaction(
 
     fSuccess = pwalletMain->CreateTransaction(vecRecipients, wtxNew, reserveKey, nFeeRequired, nChangePosRet, strFailReason, &coinControl, false);
 
+    if (fSuccess && nChangePosRet == -1 && receiverAddress == feeAddress) {
+        fSuccess = false;
+        strFailReason = "send to self without change";
+    }
+
     // to restore the original order of inputs, create a new transaction and add
     // inputs and outputs step by step
     CMutableTransaction tx;
