Merge pull request #4150

f2e65c6 wallet2: consider minimum fee when testing if balance is sufficient (stoffu)

src/wallet/wallet2.cpp

@@ -7824,6 +7824,7 @@ std::vector<wallet2::pending_tx> wallet2::create_transactions_2(std::vector<cryp
   // early out if we know we can't make it anyway
   // we could also check for being within FEE_PER_KB, but if the fee calculation
   // ever changes, this might be missed, so let this go through
+  const uint64_t min_fee = (fee_multiplier * fee_per_kb * estimate_tx_size(use_rct, 1, fake_outs_count, 2, extra.size(), bulletproof)) / 1024;
   uint64_t balance_subtotal = 0;
   uint64_t unlocked_balance_subtotal = 0;
   for (uint32_t index_minor : subaddr_indices)
@@ -7831,10 +7832,10 @@ std::vector<wallet2::pending_tx> wallet2::create_transactions_2(std::vector<cryp
     balance_subtotal += balance_per_subaddr[index_minor];
     unlocked_balance_subtotal += unlocked_balance_per_subaddr[index_minor];
   }
-  THROW_WALLET_EXCEPTION_IF(needed_money > balance_subtotal, error::not_enough_money,
+  THROW_WALLET_EXCEPTION_IF(needed_money + min_fee > balance_subtotal, error::not_enough_money,
     balance_subtotal, needed_money, 0);
   // first check overall balance is enough, then unlocked one, so we throw distinct exceptions
-  THROW_WALLET_EXCEPTION_IF(needed_money > unlocked_balance_subtotal, error::not_enough_unlocked_money,
+  THROW_WALLET_EXCEPTION_IF(needed_money + min_fee > unlocked_balance_subtotal, error::not_enough_unlocked_money,
       unlocked_balance_subtotal, needed_money, 0);
 
   for (uint32_t i : subaddr_indices)