fix: exclude net-label-only nets from MSP pair queue (closes #79)

[satyamdas03]

Problem

Pins connected only via netConnections (net labels like VCC/GND, with no directConnections) incorrectly produced routed wire traces. Since net labels already represent the electrical connection visually, drawing a wire trace between these pins creates a spurious extra line (the repro61 bug).

Root Cause

getConnectivityMapsFromInputProblem passes directConnMap.netMap by reference to new ConnectivityMap(...). When netConnMap.addConnections adds net-label entries, it mutates the same underlying object — so directConnMap.netMap ends up containing all nets, including purely-netlabel ones.

As a result, Object.keys(netConnMap.netMap) in MspConnectionPairSolver queues every net (including VCC, GND that have zero direct wires), which generates spurious MSP pairs and traces.

Fix

Build a flat Set<string> of pin IDs that appear in at least one directConnections entry. Then filter the queued net IDs to only those where at least one connected pin is in that set:

const directlyWiredPinIds = new Set<string>()
for (const dc of inputProblem.directConnections) {
  for (const pid of dc.pinIds) {
    directlyWiredPinIds.add(pid)
  }
}
this.queuedDcNetIds = Object.keys(netConnMap.netMap).filter((netId) => {
  const connectedIds = netConnMap.getIdsConnectedToNet(netId) as string[]
  return connectedIds.some((id) => directlyWiredPinIds.has(id))
})

Tests

• MspConnectionPairSolver_repro61 — verifies 0 MSP pairs for net-label-only circuits ✅
• SchematicTracePipelineSolver_repro61 — full pipeline, 0 traces generated ✅
• MspConnectionPairSolver_repro1 expectation corrected (4 → 2 pairs; GND was net-label-only) ✅
• 7 example snapshots updated (cleaner output — no more spurious GND traces) ✅
• 51 pass, 0 fail — full suite ✅

/claim #79

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Project	Deployment	Actions	Updated (UTC)
schematic-trace-solver	Ready	Preview, Comment	Apr 5, 2026 3:19am