Auto merge of #3548 - Eirik0:3546-sapling-coin-priority, r=bitcartel

Use max priority for all shielded transactions

Addresses https://github.com/zcash/zcash/issues/3546#issuecomment-425184034

qa/rpc-tests/wallet_sapling.py

@@ -53,9 +53,14 @@ class WalletSaplingTest(BitcoinTestFramework):
         recipients = []
         recipients.append({"address": saplingAddr0, "amount": Decimal('20')})
         myopid = self.nodes[0].z_sendmany(taddr0, recipients, 1, 0)
-        wait_and_assert_operationid_status(self.nodes[0], myopid)
+        mytxid = wait_and_assert_operationid_status(self.nodes[0], myopid)
 
         self.sync_all()
+
+        # Verify priority of tx is MAX_PRIORITY, defined as 1E+16 (10000000000000000)
+        mempool = self.nodes[0].getrawmempool(True)
+        assert(Decimal(mempool[mytxid]['startingpriority']) == Decimal('1E+16'))
+
         self.nodes[2].generate(1)
         self.sync_all()
 
@@ -70,9 +75,14 @@ class WalletSaplingTest(BitcoinTestFramework):
         recipients = []
         recipients.append({"address": saplingAddr1, "amount": Decimal('15')})
         myopid = self.nodes[0].z_sendmany(saplingAddr0, recipients, 1, 0)
-        wait_and_assert_operationid_status(self.nodes[0], myopid)
+        mytxid = wait_and_assert_operationid_status(self.nodes[0], myopid)
 
         self.sync_all()
+
+        # Verify priority of tx is MAX_PRIORITY, defined as 1E+16 (10000000000000000)
+        mempool = self.nodes[0].getrawmempool(True)
+        assert(Decimal(mempool[mytxid]['startingpriority']) == Decimal('1E+16'))
+
         self.nodes[2].generate(1)
         self.sync_all()
 
@@ -92,6 +102,11 @@ class WalletSaplingTest(BitcoinTestFramework):
         mytxid = wait_and_assert_operationid_status(self.nodes[1], myopid)
 
         self.sync_all()
+
+        # Verify priority of tx is MAX_PRIORITY, defined as 1E+16 (10000000000000000)
+        mempool = self.nodes[1].getrawmempool(True)
+        assert(Decimal(mempool[mytxid]['startingpriority']) == Decimal('1E+16'))
+
         self.nodes[2].generate(1)
         self.sync_all()
 

src/coins.cpp

@@ -616,16 +616,16 @@ double CCoinsViewCache::GetPriority(const CTransaction &tx, int nHeight) const
     if (tx.IsCoinBase())
         return 0.0;
 
-    // Joinsplits do not reveal any information about the value or age of a note, so we
+    // Shielded transfers do not reveal any information about the value or age of a note, so we
     // cannot apply the priority algorithm used for transparent utxos.  Instead, we just
-    // use the maximum priority whenever a transaction contains any JoinSplits.
-    // (Note that coinbase transactions cannot contain JoinSplits.)
-    // FIXME: this logic is partially duplicated between here and CreateNewBlock in miner.cpp.
+    // use the maximum priority for all (partially or fully) shielded transactions.
+    // (Note that coinbase transactions cannot contain JoinSplits, or Sapling shielded Spends or Outputs.)
 
-    if (tx.vjoinsplit.size() > 0) {
+    if (tx.vjoinsplit.size() > 0 || tx.vShieldedSpend.size() > 0 || tx.vShieldedOutput.size() > 0) {
         return MAX_PRIORITY;
     }
 
+    // FIXME: this logic is partially duplicated between here and CreateNewBlock in miner.cpp.
     double dResult = 0.0;
     BOOST_FOREACH(const CTxIn& txin, tx.vin)
     {