RPC: do not print ping info in getpeerinfo when no ping received yet, fix help

src/rpc/net.cpp

@@ -97,9 +97,9 @@ UniValue getpeerinfo(const UniValue& params, bool fHelp)
             "    \"bytesrecv\": n,            (numeric) The total bytes received\n"
             "    \"conntime\": ttt,           (numeric) The connection time in seconds since epoch (Jan 1 1970 GMT)\n"
             "    \"timeoffset\": ttt,         (numeric) The time offset in seconds\n"
-            "    \"pingtime\": n,             (numeric) ping time\n"
-            "    \"minping\": n,              (numeric) minimum observed ping time\n"
-            "    \"pingwait\": n,             (numeric) ping wait\n"
+            "    \"pingtime\": n,             (numeric) ping time (if available)\n"
+            "    \"minping\": n,              (numeric) minimum observed ping time (if any at all)\n"
+            "    \"pingwait\": n,             (numeric) ping wait (if non-zero)\n"
             "    \"version\": v,              (numeric) The peer version, such as 7001\n"
             "    \"subver\": \"/Satoshi:0.8.5/\",  (string) The string version\n"
             "    \"inbound\": true|false,     (boolean) Inbound (true) or Outbound (false)\n"
@@ -150,8 +150,10 @@ UniValue getpeerinfo(const UniValue& params, bool fHelp)
         obj.push_back(Pair("bytesrecv", stats.nRecvBytes));
         obj.push_back(Pair("conntime", stats.nTimeConnected));
         obj.push_back(Pair("timeoffset", stats.nTimeOffset));
-        obj.push_back(Pair("pingtime", stats.dPingTime));
-        obj.push_back(Pair("minping", stats.dPingMin));
+        if (stats.dPingTime > 0.0)
+            obj.push_back(Pair("pingtime", stats.dPingTime));
+        if (stats.dPingMin < std::numeric_limits<int64_t>::max()/1e6)
+            obj.push_back(Pair("minping", stats.dPingMin));
         if (stats.dPingWait > 0.0)
             obj.push_back(Pair("pingwait", stats.dPingWait));
         obj.push_back(Pair("version", stats.nVersion));