refactor: Avoid using IsArgSet() on -connect list option

This commit does not change behavior, it just changes code to handle -noconnect
values explicitly with IsArgNegated() instead of implicitly with IsArgSet(),
and adds comments to make it clear what behavior is intended when -noconnect is
specified.

Author: ryanofsky

src/init.cpp

@@ -725,8 +725,9 @@ void InitParameterInteraction(ArgsManager& args)
             LogInfo("parameter interaction: -whitebind set -> setting -listen=1\n");
     }
 
-    if (args.IsArgSet("-connect") || args.GetIntArg("-maxconnections", DEFAULT_MAX_PEER_CONNECTIONS) <= 0) {
+    if (!args.GetArgs("-connect").empty() || args.IsArgNegated("-connect") || args.GetIntArg("-maxconnections", DEFAULT_MAX_PEER_CONNECTIONS) <= 0) {
         // when only connecting to trusted nodes, do not seed via DNS, or listen by default
+        // do the same when connections are disabled
         if (args.SoftSetBoolArg("-dnsseed", false))
             LogInfo("parameter interaction: -connect or -maxconnections=0 set -> setting -dnsseed=0\n");
         if (args.SoftSetBoolArg("-listen", false))
@@ -1995,10 +1996,12 @@ bool AppInitMain(NodeContext& node, interfaces::BlockAndHeaderTipInfo* tip_info)
 
     connOptions.vSeedNodes = args.GetArgs("-seednode");
 
-    // Initiate outbound connections unless connect=0
-    connOptions.m_use_addrman_outgoing = !args.IsArgSet("-connect");
-    if (!connOptions.m_use_addrman_outgoing) {
-        const auto connect = args.GetArgs("-connect");
+    const auto connect = args.GetArgs("-connect");
+    if (!connect.empty() || args.IsArgNegated("-connect")) {
+        // Do not initiate other outgoing connections when connecting to trusted
+        // nodes, or when -noconnect is specified.
+        connOptions.m_use_addrman_outgoing = false;
+
         if (connect.size() != 1 || connect[0] != "0") {
             connOptions.m_specified_outgoing = connect;
         }