Merge pull request #165 from tscircuit/trace-layer-fix

trace layer fix for explicitly defined smtpads

lib/components/base-components/PrimitiveComponent.ts

@@ -479,7 +479,7 @@ export abstract class PrimitiveComponent<
   getAvailablePcbLayers(): string[] {
     if (this.isPcbPrimitive) {
       const { maybeFlipLayer } = this._getPcbPrimitiveFlippedHelpers()
-      if ("layer" in this._parsedProps) {
+      if ("layer" in this._parsedProps || this.componentName === "SmtPad") {
         const layer = maybeFlipLayer(this._parsedProps.layer ?? "top")
         return [layer]
       }

tests/components/normal-components/chip-layer-trace-bug.test.tsx

@@ -0,0 +1,69 @@
+import { test, expect } from "bun:test"
+import { getTestFixture } from "tests/fixtures/get-test-fixture"
+
+const FlippedChip = ({
+  name,
+  ...props
+}: { name: string; [key: string]: any }) => (
+  <group>
+    <chip {...props} name={name} layer="bottom" />
+  </group>
+)
+
+test("chip with flipped layer should have traces on correct layer", async () => {
+  const { circuit } = getTestFixture()
+
+  circuit.add(
+    <board width="20mm" height="20mm">
+      <FlippedChip
+        name="U1"
+        footprint={
+          <footprint>
+            <smtpad
+              shape="rect"
+              width="1mm"
+              height="1mm"
+              pcbX={-2}
+              pcbY={0}
+              portHints={["1"]}
+            />
+            <smtpad
+              shape="rect"
+              width="1mm"
+              height="1mm"
+              pcbX={2}
+              pcbY={0}
+              portHints={["2"]}
+            />
+          </footprint>
+        }
+        pcbX={0}
+        pcbY={0}
+      />
+      <resistor
+        name="R1"
+        resistance="10k"
+        footprint="0402"
+        pcbX={-5}
+        pcbY={0}
+      />
+      <trace from=".R1 > .pin2" to=".U1 > .1" />
+    </board>,
+  )
+
+  circuit.render()
+
+  const traces = circuit.db.pcb_trace.list()
+
+  const routeLayers = traces[0].route.flatMap((point) => {
+    if ("layer" in point) {
+      return [point.layer]
+    }
+    return [point.to_layer, point.from_layer]
+  })
+
+  expect(circuit).toMatchPcbSnapshot(import.meta.path)
+
+  expect(routeLayers).toContain("bottom")
+  expect(routeLayers).toContain("top")
+})