Merge bitcoin#15616: rpc: Clarify decodescript RPCResult doc

fa926ec rpc: Mention all output types in decodescript doc (MarcoFalke)
fa3caa1 rpc: decodescript use IsValidNumArgs over hardcoded check (MarcoFalke)
faad33f rpc: Clarify decodescript RPCResult doc (MarcoFalke)

Pull request description:

  * Remove `"hex"` from the decodescript RPCResult doc
  * Add `"segwit`" to the doc

  Follow up to a6099ef and 4f933b3

ACKs for commit fa926e:
  ryanofsky:
    utACK fa926ec. Only change since last review is listing possible output types in the help string using a new `GetAllOutputTypes` function

Tree-SHA512: e6ecc563d04769942567118d50188467bf64ceb276ba6268928d469e8f06621f2ca1ae1e555d3daa6ec22a615ee259bb31c4141c19818d0f53fb6c529b18381b

src/rpc/rawtransaction.cpp

@@ -615,33 +615,54 @@ static UniValue decoderawtransaction(const JSONRPCRequest& request)
     return result;
 }
 
+static std::string GetAllOutputTypes()
+{
+    std::string ret;
+    for (int i = TX_NONSTANDARD; i <= TX_WITNESS_UNKNOWN; ++i) {
+        if (i != TX_NONSTANDARD) ret += ", ";
+        ret += GetTxnOutputType(static_cast<txnouttype>(i));
+    }
+    return ret;
+}
+
 static UniValue decodescript(const JSONRPCRequest& request)
 {
-    if (request.fHelp || request.params.size() != 1)
-        throw std::runtime_error(
-            RPCHelpMan{"decodescript",
+    const RPCHelpMan help{"decodescript",
                 "\nDecode a hex-encoded script.\n",
                 {
                     {"hexstring", RPCArg::Type::STR_HEX, RPCArg::Optional::NO, "the hex-encoded script"},
                 },
                 RPCResult{
             "{\n"
-            "  \"asm\":\"asm\",   (string) Script public key\n"
-            "  \"hex\":\"hex\",   (string) hex-encoded public key\n"
-            "  \"type\":\"type\", (string) The output type\n"
-            "  \"reqSigs\": n,    (numeric) The required signatures\n"
-            "  \"addresses\": [   (json array of string)\n"
-            "     \"address\"     (string) bitcoin address\n"
+            "  \"asm\":\"asm\",          (string) Script public key\n"
+            "  \"type\":\"type\",        (string) The output type (e.g. "+GetAllOutputTypes()+")\n"
+            "  \"reqSigs\": n,         (numeric) The required signatures\n"
+            "  \"addresses\": [        (json array of string)\n"
+            "     \"address\"          (string) bitcoin address\n"
             "     ,...\n"
             "  ],\n"
-            "  \"p2sh\",\"address\" (string) address of P2SH script wrapping this redeem script (not returned if the script is already a P2SH).\n"
+            "  \"p2sh\":\"str\"          (string) address of P2SH script wrapping this redeem script (not returned if the script is already a P2SH).\n"
+            "  \"segwit\": {           (json object) Result of a witness script public key wrapping this redeem script (not returned if the script is a P2SH or witness).\n"
+            "    \"asm\":\"str\",        (string) String representation of the script public key\n"
+            "    \"hex\":\"hexstr\",     (string) Hex string of the script public key\n"
+            "    \"type\":\"str\",       (string) The type of the script public key (e.g. witness_v0_keyhash or witness_v0_scripthash)\n"
+            "    \"reqSigs\": n,       (numeric) The required signatures (always 1)\n"
+            "    \"addresses\": [      (json array of string) (always length 1)\n"
+            "      \"address\"         (string) segwit address\n"
+            "       ,...\n"
+            "    ],\n"
+            "    \"p2sh-segwit\":\"str\" (string) address of the P2SH script wrapping this witness redeem script.\n"
             "}\n"
                 },
                 RPCExamples{
                     HelpExampleCli("decodescript", "\"hexstring\"")
             + HelpExampleRpc("decodescript", "\"hexstring\"")
                 },
-            }.ToString());
+    };
+
+    if (request.fHelp || !help.IsValidNumArgs(request.params.size())) {
+        throw std::runtime_error(help.ToString());
+    }
 
     RPCTypeCheck(request.params, {UniValue::VSTR});
 
@@ -653,7 +674,7 @@ static UniValue decodescript(const JSONRPCRequest& request)
     } else {
         // Empty scripts are valid
     }
-    ScriptPubKeyToUniv(script, r, false);
+    ScriptPubKeyToUniv(script, r, /* fIncludeHex */ false);
 
     UniValue type;
     type = find_value(r, "type");
@@ -687,7 +708,7 @@ static UniValue decodescript(const JSONRPCRequest& request)
                 // Newer segwit program versions should be considered when then become available.
                 segwitScr = GetScriptForDestination(WitnessV0ScriptHash(script));
             }
-            ScriptPubKeyToUniv(segwitScr, sr, true);
+            ScriptPubKeyToUniv(segwitScr, sr, /* fIncludeHex */ true);
             sr.pushKV("p2sh-segwit", EncodeDestination(CScriptID(segwitScr)));
             r.pushKV("segwit", sr);
         }