Merge #16929: test: follow-up to rpc: default maxfeerate value as BTC/kB

6659810e2f38994813aa9d7644d570ae0152fa2c test: use named args for sendrawtransaction calls (Jon Atack)
5c1cd78b7e582660a78d9d9dec673967a6b78936 doc: improve rawtransaction code/test docs (Jon Atack)
acc14c50932c7353f94d3d4367d05021606e0ca9 test: fix incorrect value in rpc_rawtransaction.py (Jon Atack)

Pull request description:

  Follow-up to PR #16521.

  - Fix incorrect value in rpc_rawtransaction test as per https://github.com/bitcoin/bitcoin/pull/16521/files#r325842308
  - Improve the code docs
  - Use named arguments as per https://github.com/bitcoin/bitcoin/pull/16521/files#r310715127

  Happy to squash or keep only the first commit if the others are too fixup-y.

ACKs for top commit:
  laanwj:
    ACK 6659810e2f38994813aa9d7644d570ae0152fa2c

Tree-SHA512: bf5258f23802ab3ba3defb8791097e08e63f3e2af21023f832cd270dc88d1fa04349e921d69f9f5fedac5dce5cd3c1cc46b48febbede4bc18dccb8be994565b2

4 files changed, 19 insertions, 17 deletions

diff --git a/src/rpc/rawtransaction.cpp b/src/rpc/rawtransaction.cpp
index 461e8025da..f548d356cf 100644
--- a/src/rpc/rawtransaction.cpp
+++ b/src/rpc/rawtransaction.cpp
@@ -39,9 +39,9 @@
 
 #include <univalue.h>
 
-/** High fee rate for sendrawtransaction and testmempoolaccept.
- * By default, transaction with a fee rate higher than this will be rejected by
- * the RPCs. This can be overridden with the maxfeerate argument.
+/** Maximum fee rate for sendrawtransaction and testmempoolaccept.
+ * By default, a transaction with a fee rate higher than this will be rejected
+ * by the RPCs. This can be overridden with the maxfeerate argument.
  */
 static const CFeeRate DEFAULT_MAX_RAW_TX_FEE_RATE{COIN / 10};
 
diff --git a/test/functional/feature_segwit.py b/test/functional/feature_segwit.py
index d2826dd1b7..c69c7f90e8 100755
--- a/test/functional/feature_segwit.py
+++ b/test/functional/feature_segwit.py
@@ -257,7 +257,7 @@ class SegWitTest(BitcoinTestFramework):
         tx.vin.append(CTxIn(COutPoint(int(txid2, 16), 0), b""))
         tx.vout.append(CTxOut(int(49.95 * COIN), CScript([OP_TRUE, OP_DROP] * 15 + [OP_TRUE])))  # Huge fee
         tx.calc_sha256()
-        txid3 = self.nodes[0].sendrawtransaction(ToHex(tx), 0)
+        txid3 = self.nodes[0].sendrawtransaction(hexstring=ToHex(tx), maxfeerate=0)
         assert tx.wit.is_null()
         assert txid3 in self.nodes[0].getrawmempool()
 
@@ -566,7 +566,7 @@ class SegWitTest(BitcoinTestFramework):
             tx.vout.append(CTxOut(10000000, i))
         tx.rehash()
         signresults = self.nodes[0].signrawtransactionwithwallet(tx.serialize_without_witness().hex())['hex']
-        txid = self.nodes[0].sendrawtransaction(signresults, 0)
+        txid = self.nodes[0].sendrawtransaction(hexstring=signresults, maxfeerate=0)
         txs_mined[txid] = self.nodes[0].generate(1)[0]
         self.sync_blocks()
         watchcount = 0
@@ -618,7 +618,7 @@ class SegWitTest(BitcoinTestFramework):
         tx.vout.append(CTxOut(0, CScript()))
         tx.rehash()
         signresults = self.nodes[0].signrawtransactionwithwallet(tx.serialize_without_witness().hex())['hex']
-        self.nodes[0].sendrawtransaction(signresults, 0)
+        self.nodes[0].sendrawtransaction(hexstring=signresults, maxfeerate=0)
         self.nodes[0].generate(1)
         self.sync_blocks()
 
diff --git a/test/functional/rpc_rawtransaction.py b/test/functional/rpc_rawtransaction.py
index eb98334988..ca0d47a5f8 100755
--- a/test/functional/rpc_rawtransaction.py
+++ b/test/functional/rpc_rawtransaction.py
@@ -438,48 +438,50 @@ class RawTransactionsTest(BitcoinTestFramework):
 
         self.log.info('sendrawtransaction/testmempoolaccept with maxfeerate')
 
-        # Test a transaction with small fee
+        # Test a transaction with a small fee.
         txId = self.nodes[0].sendtoaddress(self.nodes[2].getnewaddress(), 1.0)
         rawTx = self.nodes[0].getrawtransaction(txId, True)
         vout = next(o for o in rawTx['vout'] if o['value'] == Decimal('1.00000000'))
 
         self.sync_all()
         inputs = [{ "txid" : txId, "vout" : vout['n'] }]
-        outputs = { self.nodes[0].getnewaddress() : Decimal("0.999990000") } # 10000 sat fee
+        # Fee 10,000 satoshis, (1 - (10000 sat * 0.00000001 BTC/sat)) = 0.9999
+        outputs = { self.nodes[0].getnewaddress() : Decimal("0.99990000") }
         rawTx = self.nodes[2].createrawtransaction(inputs, outputs)
         rawTxSigned = self.nodes[2].signrawtransactionwithwallet(rawTx)
         assert_equal(rawTxSigned['complete'], True)
-        # 10000 sat fee, ~100 b transaction, fee rate should land around 100 sat/b = 0.00100000 BTC/kB
+        # Fee 10,000 satoshis, ~100 b transaction, fee rate should land around 100 sat/byte = 0.00100000 BTC/kB
         # Thus, testmempoolaccept should reject
         testres = self.nodes[2].testmempoolaccept([rawTxSigned['hex']], 0.00001000)[0]
         assert_equal(testres['allowed'], False)
         assert_equal(testres['reject-reason'], '256: absurdly-high-fee')
         # and sendrawtransaction should throw
         assert_raises_rpc_error(-26, "absurdly-high-fee", self.nodes[2].sendrawtransaction, rawTxSigned['hex'], 0.00001000)
-        # And below calls should both succeed
+        # and the following calls should both succeed
         testres = self.nodes[2].testmempoolaccept(rawtxs=[rawTxSigned['hex']])[0]
         assert_equal(testres['allowed'], True)
         self.nodes[2].sendrawtransaction(hexstring=rawTxSigned['hex'])
 
-        # Test a transaction with large fee
+        # Test a transaction with a large fee.
         txId = self.nodes[0].sendtoaddress(self.nodes[2].getnewaddress(), 1.0)
         rawTx = self.nodes[0].getrawtransaction(txId, True)
         vout = next(o for o in rawTx['vout'] if o['value'] == Decimal('1.00000000'))
 
         self.sync_all()
         inputs = [{ "txid" : txId, "vout" : vout['n'] }]
-        outputs = { self.nodes[0].getnewaddress() : Decimal("0.98000000") } # 2000000 sat fee
+        # Fee 2,000,000 satoshis, (1 - (2000000 sat * 0.00000001 BTC/sat)) = 0.98
+        outputs = { self.nodes[0].getnewaddress() : Decimal("0.98000000") }
         rawTx = self.nodes[2].createrawtransaction(inputs, outputs)
         rawTxSigned = self.nodes[2].signrawtransactionwithwallet(rawTx)
         assert_equal(rawTxSigned['complete'], True)
-        # 2000000 sat fee, ~100 b transaction, fee rate should land around 20000 sat/b = 0.20000000 BTC/kB
+        # Fee 2,000,000 satoshis, ~100 b transaction, fee rate should land around 20,000 sat/byte = 0.20000000 BTC/kB
         # Thus, testmempoolaccept should reject
         testres = self.nodes[2].testmempoolaccept([rawTxSigned['hex']])[0]
         assert_equal(testres['allowed'], False)
         assert_equal(testres['reject-reason'], '256: absurdly-high-fee')
         # and sendrawtransaction should throw
         assert_raises_rpc_error(-26, "absurdly-high-fee", self.nodes[2].sendrawtransaction, rawTxSigned['hex'])
-        # And below calls should both succeed
+        # and the following calls should both succeed
         testres = self.nodes[2].testmempoolaccept(rawtxs=[rawTxSigned['hex']], maxfeerate='0.20000000')[0]
         assert_equal(testres['allowed'], True)
         self.nodes[2].sendrawtransaction(hexstring=rawTxSigned['hex'], maxfeerate='0.20000000')
diff --git a/test/functional/wallet_basic.py b/test/functional/wallet_basic.py
index 5b1c672a48..96ea5c9c35 100755
--- a/test/functional/wallet_basic.py
+++ b/test/functional/wallet_basic.py
@@ -169,8 +169,8 @@ class WalletTest(BitcoinTestFramework):
             txns_to_send.append(self.nodes[0].signrawtransactionwithwallet(raw_tx))
 
         # Have node 1 (miner) send the transactions
-        self.nodes[1].sendrawtransaction(txns_to_send[0]["hex"], 0)
-        self.nodes[1].sendrawtransaction(txns_to_send[1]["hex"], 0)
+        self.nodes[1].sendrawtransaction(hexstring=txns_to_send[0]["hex"], maxfeerate=0)
+        self.nodes[1].sendrawtransaction(hexstring=txns_to_send[1]["hex"], maxfeerate=0)
 
         # Have node1 mine a block to confirm transactions:
         self.nodes[1].generate(1)
@@ -433,7 +433,7 @@ class WalletTest(BitcoinTestFramework):
         # Split into two chains
         rawtx = self.nodes[0].createrawtransaction([{"txid": singletxid, "vout": 0}], {chain_addrs[0]: node0_balance / 2 - Decimal('0.01'), chain_addrs[1]: node0_balance / 2 - Decimal('0.01')})
         signedtx = self.nodes[0].signrawtransactionwithwallet(rawtx)
-        singletxid = self.nodes[0].sendrawtransaction(signedtx["hex"], 0)
+        singletxid = self.nodes[0].sendrawtransaction(hexstring=signedtx["hex"], maxfeerate=0)
         self.nodes[0].generate(1)
 
         # Make a long chain of unconfirmed payments without hitting mempool limit