Fix extra net label in repro61, or remove trace

lib/solvers/LongDistancePairSolver/LongDistancePairSolver.ts

@@ -52,9 +52,11 @@ export class LongDistancePairSolver extends BaseSolver {
 
     // 1. Create initial maps and sets for efficient lookup
     const primaryConnectedPinIds = new Set<PinId>()
+    const netsWithPrimaryPairs = new Set<string>()
     for (const pair of primaryMspConnectionPairs) {
       primaryConnectedPinIds.add(pair.pins[0].pinId)
       primaryConnectedPinIds.add(pair.pins[1].pinId)
+      netsWithPrimaryPairs.add(pair.globalConnNetId)
     }
 
     const { netConnMap } = getConnectivityMapsFromInputProblem(inputProblem)
@@ -74,6 +76,12 @@ export class LongDistancePairSolver extends BaseSolver {
     const addedPairKeys = new Set<string>()
 
     for (const netId of Object.keys(netConnMap.netMap)) {
+      // Long-distance routing only "fills in" pins on a net that is already
+      // partially routed via a direct connection. Nets that exist only as
+      // net-label connections should remain label-only — drawing extra traces
+      // here is the bug seen in repro61 (issue #79).
+      if (!netsWithPrimaryPairs.has(netId)) continue
+
       const allPinIdsInNet = netConnMap.getIdsConnectedToNet(netId)
       if (allPinIdsInNet.length < 2) continue
 

lib/solvers/MspConnectionPairSolver/MspConnectionPairSolver.ts

@@ -94,7 +94,11 @@ export class MspConnectionPairSolver extends BaseSolver {
 
     const dcNetId = this.queuedDcNetIds.shift()!
 
-    const allIds = this.globalConnMap.getIdsConnectedToNet(dcNetId) as string[]
+    // Only pins that share a *direct* connection should be paired into a
+    // routed trace. Pins linked only via a net connection (net label) are
+    // expressed visually by the label itself, not by an MSP-routed trace.
+    // See repro61 (tscircuit/schematic-trace-solver#79).
+    const allIds = this.dcConnMap.getIdsConnectedToNet(dcNetId) as string[]
     const directlyConnectedPins = allIds.filter((id) => !!this.pinMap[id])
 
     if (directlyConnectedPins.length <= 1) {

lib/solvers/MspConnectionPairSolver/getConnectivityMapFromInputProblem.ts

@@ -14,7 +14,11 @@ export const getConnectivityMapsFromInputProblem = (
     ])
   }
 
-  const netConnMap = new ConnectivityMap(directConnMap.netMap)
+  // ConnectivityMap stores the netMap by reference; if we passed
+  // `directConnMap.netMap` directly, subsequent `netConnMap.addConnections`
+  // calls would mutate `directConnMap` too, polluting the "direct only" view.
+  // Clone so the two maps stay independent. (See repro61, tscircuit/schematic-trace-solver#79.)
+  const netConnMap = new ConnectivityMap(structuredClone(directConnMap.netMap))
 
   for (const netConn of inputProblem.netConnections) {
     netConnMap.addConnections([[netConn.netId, ...netConn.pinIds]])