Merge #20556: rpc: Properly document return values (submitblock, gettxout, getblocktemplate, scantxoutset)

fa7ff0790e rpc: Properly document submitblock return value (MarcoFalke)
fae542c28b rpc: Properly document getblocktemplate return value (MarcoFalke)
fabaccf031 rpc: Properly document scantxoutset return value (MarcoFalke)
faa2059547 rpc: Properly document gettxout return value (MarcoFalke)

Pull request description:

  Currently a few return values are undocumented. This is causing confusion at the least. See for example #18476

ACKs for top commit:
  fjahr:
    utACK fa7ff0790e
  amitiuttarwar:
    tACK fa7ff0790e

Tree-SHA512: 933cb8f003163d93dbedb302d4c162514c2698ec6d58dbb9a053da8b8b9a4459b0701a3d9e830ecdabd7f278a46b7a07a3af49ec60703a80fcd75390877294ea

src/rpc/blockchain.cpp

@@ -1106,23 +1106,22 @@ static RPCHelpMan gettxout()
             {"n", RPCArg::Type::NUM, RPCArg::Optional::NO, "vout number"},
             {"include_mempool", RPCArg::Type::BOOL, /* default */ "true", "Whether to include the mempool. Note that an unspent output that is spent in the mempool won't appear."},
         },
-                RPCResult{
-                    RPCResult::Type::OBJ, "", "",
         {
+            RPCResult{"If the UTXO was not found", RPCResult::Type::NONE, "", ""},
+            RPCResult{"Otherwise", RPCResult::Type::OBJ, "", "", {
                 {RPCResult::Type::STR_HEX, "bestblock", "The hash of the block at the tip of the chain"},
                 {RPCResult::Type::NUM, "confirmations", "The number of confirmations"},
                 {RPCResult::Type::STR_AMOUNT, "value", "The transaction value in " + CURRENCY_UNIT},
-                        {RPCResult::Type::OBJ, "scriptPubKey", "",
-                            {
+                {RPCResult::Type::OBJ, "scriptPubKey", "", {
                     {RPCResult::Type::STR_HEX, "asm", ""},
                     {RPCResult::Type::STR_HEX, "hex", ""},
                     {RPCResult::Type::NUM, "reqSigs", "Number of required signatures"},
                     {RPCResult::Type::STR_HEX, "type", "The type, eg pubkeyhash"},
-                                {RPCResult::Type::ARR, "addresses", "array of bitcoin addresses",
-                                    {{RPCResult::Type::STR, "address", "bitcoin address"}}},
+                    {RPCResult::Type::ARR, "addresses", "array of bitcoin addresses", {{RPCResult::Type::STR, "address", "bitcoin address"}}},
                 }},
                 {RPCResult::Type::BOOL, "coinbase", "Coinbase or not"},
             }},
+        },
         RPCExamples{
             "\nGet unspent transactions\n"
             + HelpExampleCli("listunspent", "") +
@@ -2152,25 +2151,29 @@ static RPCHelpMan scantxoutset()
         "For more information on output descriptors, see the documentation in the doc/descriptors.md file.\n",
         {
             {"action", RPCArg::Type::STR, RPCArg::Optional::NO, "The action to execute\n"
-            "                                      \"start\" for starting a scan\n"
-            "                                      \"abort\" for aborting the current scan (returns true when abort was successful)\n"
-            "                                      \"status\" for progress report (in %) of the current scan"},
+                "\"start\" for starting a scan\n"
+                "\"abort\" for aborting the current scan (returns true when abort was successful)\n"
+                "\"status\" for progress report (in %) of the current scan"},
             {"scanobjects", RPCArg::Type::ARR, RPCArg::Optional::OMITTED, "Array of scan objects. Required for \"start\" action\n"
-            "                                  Every scan object is either a string descriptor or an object:",
+                "Every scan object is either a string descriptor or an object:",
             {
                 {"descriptor", RPCArg::Type::STR, RPCArg::Optional::OMITTED, "An output descriptor"},
                 {"", RPCArg::Type::OBJ, RPCArg::Optional::OMITTED, "An object with output descriptor and metadata",
                 {
                     {"desc", RPCArg::Type::STR, RPCArg::Optional::NO, "An output descriptor"},
                     {"range", RPCArg::Type::RANGE, /* default */ "1000", "The range of HD chain indexes to explore (either end or [begin,end])"},
-                                },
-                            },
+                }},
             },
                         "[scanobjects,...]"},
         },
-                RPCResult{
-                    RPCResult::Type::OBJ, "", "",
         {
+            RPCResult{"When action=='abort'", RPCResult::Type::BOOL, "", ""},
+            RPCResult{"When action=='status' and no scan is in progress", RPCResult::Type::NONE, "", ""},
+            RPCResult{"When action=='status' and scan is in progress", RPCResult::Type::OBJ, "", "",
+            {
+                {RPCResult::Type::NUM, "progress", "The scan progress"},
+            }},
+            RPCResult{"When action=='start'", RPCResult::Type::OBJ, "", "", {
                 {RPCResult::Type::BOOL, "success", "Whether the scan was completed"},
                 {RPCResult::Type::NUM, "txouts", "The number of unspent transaction outputs scanned"},
                 {RPCResult::Type::NUM, "height", "The current block height (index)"},
@@ -2189,6 +2192,7 @@ static RPCHelpMan scantxoutset()
                 }},
                 {RPCResult::Type::STR_AMOUNT, "total_amount", "The total amount of all found unspent outputs in " + CURRENCY_UNIT},
             }},
+        },
         RPCExamples{""},
         [&](const RPCHelpMan& self, const JSONRPCRequest& request) -> UniValue
 {

src/rpc/mining.cpp

@@ -519,19 +519,19 @@ static RPCHelpMan getblocktemplate()
                 {"capabilities", RPCArg::Type::ARR, /* treat as named arg */ RPCArg::Optional::OMITTED_NAMED_ARG, "A list of strings",
                 {
                     {"str", RPCArg::Type::STR, RPCArg::Optional::OMITTED, "client side supported feature, 'longpoll', 'coinbasevalue', 'proposal', 'serverlist', 'workid'"},
-                                },
-                                },
+                }},
                 {"rules", RPCArg::Type::ARR, RPCArg::Optional::NO, "A list of strings",
                 {
                     {"segwit", RPCArg::Type::STR, RPCArg::Optional::NO, "(literal) indicates client side segwit support"},
                     {"str", RPCArg::Type::STR, RPCArg::Optional::OMITTED, "other client side supported softfork deployment"},
-                                },
-                                },
+                }},
             },
                         "\"template_request\""},
         },
-                RPCResult{
-                    RPCResult::Type::OBJ, "", "",
+        {
+            RPCResult{"If the proposal was accepted with mode=='proposal'", RPCResult::Type::NONE, "", ""},
+            RPCResult{"If the proposal was not accepted with mode=='proposal'", RPCResult::Type::STR, "", "According to BIP22"},
+            RPCResult{"Otherwise", RPCResult::Type::OBJ, "", "",
             {
                 {RPCResult::Type::NUM, "version", "The preferred block version"},
                 {RPCResult::Type::ARR, "rules", "specific block rules that are to be enforced",
@@ -579,8 +579,9 @@ static RPCHelpMan getblocktemplate()
                 {RPCResult::Type::NUM_TIME, "curtime", "current timestamp in " + UNIX_EPOCH_TIME},
                 {RPCResult::Type::STR, "bits", "compressed target of next block"},
                 {RPCResult::Type::NUM, "height", "The height of the next block"},
-                        {RPCResult::Type::STR, "default_witness_commitment", /* optional */ true, "a valid witness commitment for the unmodified block template"}
+                {RPCResult::Type::STR, "default_witness_commitment", /* optional */ true, "a valid witness commitment for the unmodified block template"},
             }},
+        },
         RPCExamples{
                     HelpExampleCli("getblocktemplate", "'{\"rules\": [\"segwit\"]}'")
             + HelpExampleRpc("getblocktemplate", "{\"rules\": [\"segwit\"]}")
@@ -946,7 +947,10 @@ static RPCHelpMan submitblock()
             {"hexdata", RPCArg::Type::STR_HEX, RPCArg::Optional::NO, "the hex-encoded block data to submit"},
             {"dummy", RPCArg::Type::STR, /* default */ "ignored", "dummy value, for compatibility with BIP22. This value is ignored."},
         },
-                RPCResult{RPCResult::Type::NONE, "", "Returns JSON Null when valid, a string according to BIP22 otherwise"},
+        {
+            RPCResult{"If the block was accepted", RPCResult::Type::NONE, "", ""},
+            RPCResult{"Otherwise", RPCResult::Type::STR, "", "According to BIP22"},
+        },
         RPCExamples{
                     HelpExampleCli("submitblock", "\"mydata\"")
             + HelpExampleRpc("submitblock", "\"mydata\"")