New LLMQ-based IS should have no legacy IS strings in UI and no legacy restrictions (#2883)

(max value/too many inputs/additional fees)

src/qt/sendcoinsdialog.cpp

@@ -269,14 +269,14 @@ void SendCoinsDialog::on_sendButton_clicked()
         strFunds = tr("using") + " <b>" + tr("any available funds (not anonymous)") + "</b>";
     }
 
-    if(ui->checkUseInstantSend->isChecked()) {
+    if(model->IsOldInstantSendEnabled() && ui->checkUseInstantSend->isChecked()) {
         strFunds += " ";
         strFunds += tr("and InstantSend");
     }
 
     for (SendCoinsRecipient& rcp : recipients) {
         rcp.inputType = ui->checkUsePrivateSend->isChecked() ? ONLY_DENOMINATED : ALL_COINS;
-        rcp.fUseInstantSend = ui->checkUseInstantSend->isChecked();
+        rcp.fUseInstantSend = model->IsOldInstantSendEnabled() && ui->checkUseInstantSend->isChecked();
     }
 
     fNewRecipientAllowed = false;
@@ -611,7 +611,7 @@ void SendCoinsDialog::updateInstantSend()
 {
     QSettings settings;
     settings.setValue("bUseInstantX", ui->checkUseInstantSend->isChecked());
-    CoinControlDialog::coinControl->fUseInstantSend = ui->checkUseInstantSend->isChecked();
+    CoinControlDialog::coinControl->fUseInstantSend = model->IsOldInstantSendEnabled() && ui->checkUseInstantSend->isChecked();
     coinControlUpdateLabels();
 }
 

src/qt/walletmodel.cpp

@@ -216,6 +216,11 @@ int WalletModel::getNumISLocks() const
     return cachedNumISLocks;
 }
 
+bool WalletModel::IsOldInstantSendEnabled() const
+{
+    return llmq::IsOldInstantSendEnabled();
+}
+
 void WalletModel::updateAddressBook(const QString &address, const QString &label,
         bool isMine, const QString &purpose, int status)
 {
@@ -314,7 +319,7 @@ WalletModel::SendCoinsReturn WalletModel::prepareTransaction(WalletModelTransact
         return AmountExceedsBalance;
     }
 
-    if(recipients[0].fUseInstantSend && total > sporkManager.GetSporkValue(SPORK_5_INSTANTSEND_MAX_VALUE)*COIN) {
+    if(recipients[0].fUseInstantSend && IsOldInstantSendEnabled() && total > sporkManager.GetSporkValue(SPORK_5_INSTANTSEND_MAX_VALUE)*COIN) {
         Q_EMIT message(tr("Send Coins"), tr("InstantSend doesn't support sending values that high yet. Transactions are currently limited to %1 DASH.").arg(sporkManager.GetSporkValue(SPORK_5_INSTANTSEND_MAX_VALUE)),
                      CClientUIInterface::MSG_ERROR);
         return TransactionCreationFailed;
@@ -344,7 +349,7 @@ WalletModel::SendCoinsReturn WalletModel::prepareTransaction(WalletModelTransact
         nVinSize = newTx->tx->vin.size();
     }
 
-    if(recipients[0].fUseInstantSend) {
+    if(recipients[0].fUseInstantSend && IsOldInstantSendEnabled()) {
         if(nValueOut > sporkManager.GetSporkValue(SPORK_5_INSTANTSEND_MAX_VALUE)*COIN) {
             Q_EMIT message(tr("Send Coins"), tr("InstantSend doesn't support sending values that high yet. Transactions are currently limited to %1 DASH.").arg(sporkManager.GetSporkValue(SPORK_5_INSTANTSEND_MAX_VALUE)),
                          CClientUIInterface::MSG_ERROR);
@@ -410,7 +415,7 @@ WalletModel::SendCoinsReturn WalletModel::sendCoins(WalletModelTransaction &tran
         CValidationState state;
         // the new IX system does not require explicit IX messages
         std::string strCommand = NetMsgType::TX;
-        if (recipients[0].fUseInstantSend && llmq::IsOldInstantSendEnabled()) {
+        if (recipients[0].fUseInstantSend && IsOldInstantSendEnabled()) {
             strCommand = NetMsgType::TXLOCKREQUEST;
         }
         if(!wallet->CommitTransaction(*newTx, *keyChange, g_connman.get(), state, strCommand))

src/qt/walletmodel.h

@@ -228,6 +228,8 @@ public:
     int getDefaultConfirmTarget() const;
     int getNumISLocks() const;
 
+    bool IsOldInstantSendEnabled() const;
+
 private:
     CWallet *wallet;
     bool fHaveWatchOnly;

src/wallet/wallet.cpp

@@ -2590,6 +2590,12 @@ static void ApproximateBestSubset(std::vector<std::pair<CAmount, std::pair<const
     vfBest.assign(vValue.size(), true);
     nBest = nTotalLower;
 
+    if (!llmq::IsOldInstantSendEnabled()) {
+        // The new system does not require special handling for InstantSend as this is all done in CInstantSendManager.
+        // There is also no need for an extra fee anymore.
+        fUseInstantSend = false;
+    }
+
     FastRandomContext insecure_rand;
 
     for (int nRep = 0; nRep < iterations && nBest != nTargetValue; nRep++)
@@ -2662,6 +2668,12 @@ bool CWallet::SelectCoinsMinConf(const CAmount& nTargetValue, const int nConfMin
     setCoinsRet.clear();
     nValueRet = 0;
 
+    if (!llmq::IsOldInstantSendEnabled()) {
+        // The new system does not require special handling for InstantSend as this is all done in CInstantSendManager.
+        // There is also no need for an extra fee anymore.
+        fUseInstantSend = false;
+    }
+
     // List of values less than target
     std::pair<CAmount, std::pair<const CWalletTx*,unsigned int> > coinLowestLarger;
     coinLowestLarger.first = fUseInstantSend