wallet: improve error messages when not enough money for transfer

src/simplewallet/simplewallet.cpp

@@ -2549,13 +2549,20 @@ bool simple_wallet::transfer_main(int transfer_type, const std::vector<std::stri
     fail_msg_writer() << tr("failed to get random outputs to mix");
   }
   catch (const tools::error::not_enough_money& e)
+  {
+    LOG_PRINT_L0(boost::format("not enough money to transfer, available only %s, sent amount %s") %
+      print_money(e.available()) %
+      print_money(e.tx_amount()));
+    fail_msg_writer() << tr("Not enough money in unlocked balance");
+  }
+  catch (const tools::error::tx_not_possible& e)
   {
     LOG_PRINT_L0(boost::format("not enough money to transfer, available only %s, transaction amount %s = %s + %s (fee)") %
       print_money(e.available()) %
       print_money(e.tx_amount() + e.fee())  %
       print_money(e.tx_amount()) %
       print_money(e.fee()));
-    fail_msg_writer() << tr("Failed to find a way to create transactions. This is usually due to dust which is so small it cannot pay for itself in fees");
+    fail_msg_writer() << tr("Failed to find a way to create transactions. This is usually due to dust which is so small it cannot pay for itself in fees, or trying to send more money than the unlocked balance, or not leaving enough for fees");
   }
   catch (const tools::error::not_enough_outs_to_mix& e)
   {
@@ -2810,13 +2817,20 @@ bool simple_wallet::locked_transfer(const std::vector<std::string> &args_)
     fail_msg_writer() << tr("failed to get random outputs to mix");
   }
   catch (const tools::error::not_enough_money& e)
+  {
+    LOG_PRINT_L0(boost::format("not enough money to transfer, available only %s, sent amount %s") %
+      print_money(e.available()) %
+      print_money(e.tx_amount()));
+    fail_msg_writer() << tr("Not enough money in unlocked balance");
+  }
+  catch (const tools::error::tx_not_possible& e)
   {
     LOG_PRINT_L0(boost::format("not enough money to transfer, available only %s, transaction amount %s = %s + %s (fee)") %
       print_money(e.available()) %
       print_money(e.tx_amount() + e.fee())  %
       print_money(e.tx_amount()) %
       print_money(e.fee()));
-    fail_msg_writer() << tr("Not enough money to transfer.");
+    fail_msg_writer() << tr("Failed to find a way to create transactions. This is usually due to dust which is so small it cannot pay for itself in fees, or trying to send more money than the unlocked balance, or not leaving enough for fees");
   }
   catch (const tools::error::not_enough_outs_to_mix& e)
   {
@@ -2969,13 +2983,20 @@ bool simple_wallet::sweep_unmixable(const std::vector<std::string> &args_)
     fail_msg_writer() << tr("failed to get random outputs to mix");
   }
   catch (const tools::error::not_enough_money& e)
+  {
+    LOG_PRINT_L0(boost::format("not enough money to transfer, available only %s, sent amount %s") %
+      print_money(e.available()) %
+      print_money(e.tx_amount()));
+    fail_msg_writer() << tr("Not enough money in unlocked balance");
+  }
+  catch (const tools::error::tx_not_possible& e)
   {
     LOG_PRINT_L0(boost::format("not enough money to transfer, available only %s, transaction amount %s = %s + %s (fee)") %
       print_money(e.available()) %
       print_money(e.tx_amount() + e.fee())  %
       print_money(e.tx_amount()) %
       print_money(e.fee()));
-    fail_msg_writer() << tr("Failed to find a way to create transactions. This is usually due to dust which is so small it cannot pay for itself in fees");
+    fail_msg_writer() << tr("Failed to find a way to create transactions. This is usually due to dust which is so small it cannot pay for itself in fees, or trying to send more money than the unlocked balance, or not leaving enough for fees");
   }
   catch (const tools::error::not_enough_outs_to_mix& e)
   {
@@ -3224,13 +3245,20 @@ bool simple_wallet::sweep_all(const std::vector<std::string> &args_)
     fail_msg_writer() << tr("failed to get random outputs to mix");
   }
   catch (const tools::error::not_enough_money& e)
+  {
+    LOG_PRINT_L0(boost::format("not enough money to transfer, available only %s, sent amount %s") %
+      print_money(e.available()) %
+      print_money(e.tx_amount()));
+    fail_msg_writer() << tr("Not enough money in unlocked balance");
+  }
+  catch (const tools::error::tx_not_possible& e)
   {
     LOG_PRINT_L0(boost::format("not enough money to transfer, available only %s, transaction amount %s = %s + %s (fee)") %
       print_money(e.available()) %
       print_money(e.tx_amount() + e.fee())  %
       print_money(e.tx_amount()) %
       print_money(e.fee()));
-    fail_msg_writer() << tr("Failed to find a way to create transactions. This is usually due to dust which is so small it cannot pay for itself in fees");
+    fail_msg_writer() << tr("Failed to find a way to create transactions. This is usually due to dust which is so small it cannot pay for itself in fees, or trying to send more money than the unlocked balance, or not leaving enough for fees");
   }
   catch (const tools::error::not_enough_outs_to_mix& e)
   {
@@ -3458,11 +3486,19 @@ bool simple_wallet::submit_transfer(const std::vector<std::string> &args_)
   }
   catch (const tools::error::not_enough_money& e)
   {
-    fail_msg_writer() << boost::format(tr("not enough money to transfer, available only %s, transaction amount %s = %s + %s (fee)")) %
+    LOG_PRINT_L0(boost::format("not enough money to transfer, available only %s, sent amount %s") %
+      print_money(e.available()) %
+      print_money(e.tx_amount()));
+    fail_msg_writer() << tr("Not enough money in unlocked balance");
+  }
+  catch (const tools::error::tx_not_possible& e)
+  {
+    LOG_PRINT_L0(boost::format("not enough money to transfer, available only %s, transaction amount %s = %s + %s (fee)") %
       print_money(e.available()) %
       print_money(e.tx_amount() + e.fee())  %
       print_money(e.tx_amount()) %
-      print_money(e.fee());
+      print_money(e.fee()));
+    fail_msg_writer() << tr("Failed to find a way to create transactions. This is usually due to dust which is so small it cannot pay for itself in fees, or trying to send more money than the unlocked balance, or not leaving enough for fees");
   }
   catch (const tools::error::not_enough_outs_to_mix& e)
   {

src/wallet/api/wallet.cpp

@@ -595,6 +595,15 @@ PendingTransaction *WalletImpl::createTransaction(const string &dst_addr, const
             m_status = Status_Error;
             std::ostringstream writer;
 
+            writer << boost::format(tr("not enough money to transfer, available only %s, sent amount %s")) %
+                      print_money(e.available()) %
+                      print_money(e.tx_amount());
+            m_errorString = writer.str();
+
+        } catch (const tools::error::tx_not_possible& e) {
+            m_status = Status_Error;
+            std::ostringstream writer;
+
             writer << boost::format(tr("not enough money to transfer, available only %s, transaction amount %s = %s + %s (fee)")) %
                       print_money(e.available()) %
                       print_money(e.tx_amount() + e.fee())  %

src/wallet/wallet2.cpp

@@ -3457,6 +3457,12 @@ std::vector<wallet2::pending_tx> wallet2::create_transactions_2(std::vector<cryp
   }
   LOG_PRINT_L2("Starting with " << unused_transfers_indices.size() << " non-dust outputs and " << unused_dust_indices.size() << " dust outputs");
 
+  // 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
+  THROW_WALLET_EXCEPTION_IF(needed_money > unlocked_balance(), error::not_enough_money,
+      unlocked_balance(), needed_money, 0);
+
   if (unused_dust_indices.empty() && unused_transfers_indices.empty())
     return std::vector<wallet2::pending_tx>();
 
@@ -3497,7 +3503,7 @@ std::vector<wallet2::pending_tx> wallet2::create_transactions_2(std::vector<cryp
     // if we need to spend money and don't have any left, we fail
     if (unused_dust_indices.empty() && unused_transfers_indices.empty()) {
       LOG_PRINT_L2("No more outputs to choose from");
-      THROW_WALLET_EXCEPTION_IF(1, error::not_enough_money, unlocked_balance(), needed_money, accumulated_fee + needed_fee);
+      THROW_WALLET_EXCEPTION_IF(1, error::tx_not_possible, unlocked_balance(), needed_money, accumulated_fee + needed_fee);
     }
 
     // get a random unspent output and use it to pay part (or all) of the current destination (and maybe next one, etc)
@@ -3637,7 +3643,7 @@ std::vector<wallet2::pending_tx> wallet2::create_transactions_2(std::vector<cryp
   if (adding_fee)
   {
     LOG_PRINT_L1("We ran out of outputs while trying to gather final fee");
-    THROW_WALLET_EXCEPTION_IF(1, error::not_enough_money, unlocked_balance(), needed_money, accumulated_fee + needed_fee);
+    THROW_WALLET_EXCEPTION_IF(1, error::tx_not_possible, unlocked_balance(), needed_money, accumulated_fee + needed_fee);
   }
 
   LOG_PRINT_L1("Done creating " << txes.size() << " transactions, " << print_money(accumulated_fee) <<

src/wallet/wallet_errors.h

@@ -68,6 +68,7 @@ namespace tools
     //       transfer_error *
     //         get_random_outs_general_error
     //         not_enough_money
+    //         tx_not_possible
     //         not_enough_outs_to_mix
     //         tx_not_constructed
     //         tx_rejected
@@ -351,6 +352,32 @@ namespace tools
         : transfer_error(std::move(loc), "not enough money")
         , m_available(availbable)
         , m_tx_amount(tx_amount)
+      {
+      }
+
+      uint64_t available() const { return m_available; }
+      uint64_t tx_amount() const { return m_tx_amount; }
+
+      std::string to_string() const
+      {
+        std::ostringstream ss;
+        ss << transfer_error::to_string() <<
+          ", available = " << cryptonote::print_money(m_available) <<
+          ", tx_amount = " << cryptonote::print_money(m_tx_amount);
+        return ss.str();
+      }
+
+    private:
+      uint64_t m_available;
+      uint64_t m_tx_amount;
+    };
+    //----------------------------------------------------------------------------------------------------
+    struct tx_not_possible : public transfer_error
+    {
+      explicit tx_not_possible(std::string&& loc, uint64_t availbable, uint64_t tx_amount, uint64_t fee)
+        : transfer_error(std::move(loc), "tx not possible")
+        , m_available(availbable)
+        , m_tx_amount(tx_amount)
         , m_fee(fee)
       {
       }