[rpc] fundrawtransaction: Fix help text and interface

qa/rpc-tests/fundrawtransaction.py

@@ -681,7 +681,7 @@ class RawTransactionsTest(BitcoinTestFramework):
         inputs = []
         outputs = {self.nodes[2].getnewaddress() : 1}
         rawtx = self.nodes[3].createrawtransaction(inputs, outputs)
-        result = self.nodes[3].fundrawtransaction(rawtx, )
+        result = self.nodes[3].fundrawtransaction(rawtx) # 1000 sat via settxfee
         result2 = self.nodes[3].fundrawtransaction(rawtx, {"feeRate": 2000})
         result3 = self.nodes[3].fundrawtransaction(rawtx, {"feeRate": 10000})
         assert_equal(result['fee']*2, result2['fee'])

src/wallet/rpcwallet.cpp

@@ -2369,13 +2369,13 @@ UniValue fundrawtransaction(const UniValue& params, bool fHelp)
                             "     \"changePosition\"    (numeric, optional, default random) The index of the change output\n"
                             "     \"includeWatching\"   (boolean, optional, default false) Also select inputs which are watch only\n"
                             "     \"lockUnspents\"      (boolean, optional, default false) Lock selected unspent outputs\n"
-                            "     \"feeRate\"           (numeric, optional, default 0=estimate) Set a specific feerate (fee per KB)\n"
+                            "     \"feeRate\"           (numeric, optional, default not set: makes wallet determine the fee) Set a specific feerate (satoshis per KB)\n"
                             "   }\n"
                             "                         for backward compatibility: passing in a true instead of an object will result in {\"includeWatching\":true}\n"
                             "\nResult:\n"
                             "{\n"
                             "  \"hex\":       \"value\", (string)  The resulting raw transaction (hex-encoded string)\n"
-                            "  \"fee\":       n,         (numeric) Fee the resulting transaction pays\n"
+                            "  \"fee\":       n,         (numeric) Fee in " + CURRENCY_UNIT + " the resulting transaction pays\n"
                             "  \"changepos\": n          (numeric) The position of the added change output, or -1\n"
                             "}\n"
                             "\"hex\"             \n"