fix net-based differential pairs in autorouting phases

lib/components/primitive-components/Group/Group_getRoutingPhasePlans.ts

@@ -128,13 +128,14 @@ function traceHasEndpointMatchingConnectionSelector(
   trace: Trace,
   connectionSelectorEndpointKey: string,
 ): boolean {
-  return trace
-    .getTracePortPathSelectors()
-    .some(
-      (selector) =>
-        convertPortSelectorToEndpointKey(selector) ===
-        connectionSelectorEndpointKey,
-    )
+  return [
+    ...trace.getTracePortPathSelectors(),
+    ...trace.getTracePathNetSelectors(),
+  ].some(
+    (selector) =>
+      convertPortSelectorToEndpointKey(selector) ===
+      connectionSelectorEndpointKey,
+  )
 }
 
 function getAutoroutersByPhaseIndex(
@@ -307,6 +308,19 @@ export function Group_getRoutingPhasePlans(
         convertPortSelectorToEndpointKey,
       )
       plan.connectionSelectors = connectionSelectors
+      for (const selector of connectionSelectors) {
+        const net = group.selectOne<Net>(selector, { type: "net" })
+        if (!net || breakoutByNet.has(net)) continue
+        if (!phaseProps.reroute) {
+          for (const existingPlan of plansByPhaseIndex.values()) {
+            if (existingPlan === plan) continue
+            existingPlan.nets = existingPlan.nets.filter(
+              (existingNet) => existingNet !== net,
+            )
+          }
+        }
+        if (!plan.nets.includes(net)) plan.nets.push(net)
+      }
 
       for (const trace of traces) {
         if (breakoutByTrace.has(trace)) continue

lib/components/primitive-components/Group/Group_phasedAutoroutingUtils.ts

@@ -21,6 +21,12 @@ export function connectionIsInRoutingPhase(
   for (const trace of phasePlan.traces) {
     if (!trace.source_trace_id) continue
     if (connection.source_trace_id === trace.source_trace_id) return true
+    // Breakouts use their split, group-owned connections, not the whole net.
+    if (
+      !phasePlan.routingPcbGroupId &&
+      connection.source_trace_ids?.includes(trace.source_trace_id)
+    )
+      return true
     if (connection.name === trace.source_trace_id) return true
     if (connection.rootConnectionName === trace.source_trace_id) return true
     if (connection.mergedConnectionNames?.includes(trace.source_trace_id)) {

lib/utils/autorouting/SimpleRouteJson.ts

@@ -2,7 +2,7 @@ import type {
   SimpleRouteJson as AutorouterSimpleRouteJson,
   SimplifiedPcbTrace as AutorouterSimplifiedPcbTrace,
 } from "@tscircuit/capacity-autorouter"
-import type { PcbGroup } from "circuit-json"
+import type { PcbGroup, SourceTrace } from "circuit-json"
 import type { CircuitJsonMetadata, Obstacle } from "../obstacles/types"
 
 export type { CircuitJsonMetadata, Obstacle } from "../obstacles/types"
@@ -83,6 +83,8 @@ export type SimpleRouteConnection = {
   name: SrjConnectionName
   routingPcbGroupId?: PcbGroupId
   source_trace_id?: string
+  /** Source traces combined into a net-based routing connection. */
+  source_trace_ids?: SourceTrace["source_trace_id"][]
   rootConnectionName?: string
   mergedConnectionNames?: string[]
   isOffBoard?: boolean

lib/utils/autorouting/getDifferentialPairsForSimpleRouteJson.ts

@@ -137,8 +137,13 @@ const getDifferentialPairSrjConnectionNamesByCohortOrThrow = ({
   const matchingSrjConnections: SimpleRouteConnection[] = []
   for (const srjConnection of srjConnections) {
     if (
-      srjConnection.source_trace_id &&
-      differentialPairSourceTraceIds.includes(srjConnection.source_trace_id)
+      (srjConnection.source_trace_id &&
+        differentialPairSourceTraceIds.includes(
+          srjConnection.source_trace_id,
+        )) ||
+      srjConnection.source_trace_ids?.some((sourceTraceId) =>
+        differentialPairSourceTraceIds.includes(sourceTraceId),
+      )
     ) {
       matchingSrjConnections.push(srjConnection)
     }

lib/utils/autorouting/getSimpleRouteJsonFromCircuitJson.ts

@@ -709,6 +709,9 @@ export const getSimpleRouteJsonFromCircuitJson = ({
       name:
         net.source_net_id ??
         sharedConnMap.getNetConnectedToId(net.source_net_id),
+      source_trace_ids: connectedSourceTraces.map(
+        (sourceTrace) => sourceTrace.source_trace_id,
+      ),
       nominalTraceWidth: nominalTraceWidthFromConnectedTraces,
       width: nominalTraceWidthFromConnectedTraces,
       pointsToConnect,

tests/components/primitive-components/differential-pair/net-fragments-point-to-point.test.tsx

@@ -1,4 +1,5 @@
 import { expect, test } from "bun:test"
+import { getSimpleRouteJsonFromCircuitJson } from "lib/utils/autorouting/getSimpleRouteJsonFromCircuitJson"
 import { getTestFixture } from "tests/fixtures/get-test-fixture"
 
 test("does not warn for a two-terminal conductor split through a source net", (): void => {
@@ -30,4 +31,20 @@ test("does not warn for a two-terminal conductor split through a source net", ()
           warning.property_name === "negativeConnection",
       ),
   ).toEqual([])
+
+  const board = circuit.firstChild
+  if (!board) throw new Error("Expected a board")
+  const { simpleRouteJson } = getSimpleRouteJsonFromCircuitJson({
+    db: circuit.db,
+    subcircuitComponent: board,
+  })
+  expect(simpleRouteJson.differentialPairs).toEqual([
+    {
+      connectionNames: [
+        circuit.db.source_net.getWhere({ name: "DP" })!.source_net_id,
+        circuit.db.source_trace.getWhere({ name: "DM" })!.source_trace_id,
+      ],
+      lengthTolerance: 0.1,
+    },
+  ])
 })

tests/repros/usb-c-breakout-net-pair.test.tsx

@@ -1,25 +1,21 @@
 import { expect, test } from "bun:test"
-import { getSimpleRouteJsonFromCircuitJson } from "lib/utils/autorouting/getSimpleRouteJsonFromCircuitJson"
+import { createAutoroutingPhaseIoStack } from "tests/fixtures/create-autorouting-phase-io-stack"
 import { getTestFixture } from "tests/fixtures/get-test-fixture"
 
 import UsbBreakoutBoard from "./usb-c-breakout/board"
 
 test("USB-C breakout pair wired through named nets", async () => {
   const { circuit } = getTestFixture()
+  const phases = createAutoroutingPhaseIoStack(circuit)
   circuit.add(<UsbBreakoutBoard />)
   await circuit.renderUntilSettled()
   expect(circuit.db.source_failed_to_create_component_error.list()).toEqual([])
   expect(circuit.db.source_trace_not_connected_error.list()).toEqual([])
-  const board = circuit.firstChild
-  if (!board) throw new Error("Expected USB-C breakout board")
-  expect(() =>
-    getSimpleRouteJsonFromCircuitJson({
-      db: circuit.db,
-      subcircuitComponent: board,
-    }),
-  ).toThrow(
-    'Could not find an SRJ connection for trace name or port selector ".R3 > .pin1"',
-  )
-  expect(circuit.db.pcb_trace.list()).toHaveLength(0)
+  expect(phases).toHaveLength(2)
+  expect(phases[0]?.startSimpleRouteJson?.differentialPairs).toHaveLength(1)
+  expect(phases[0]?.endSimpleRouteJson?.traces).toHaveLength(2)
+  expect(circuit.db.pcb_autorouting_error.list()).toEqual([])
+  expect(circuit.db.pcb_trace_error.list()).toEqual([])
+  expect(circuit.db.pcb_port_not_connected_error.list()).toEqual([])
   await expect(circuit).toMatchPcbSnapshot(import.meta.path)
 }, 30_000)