test: repro #655 — net labels are placed inside chip bodies

tests/repros/repro-net-label-inside-chip-655.test.ts

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+import { expect, test } from "bun:test"
+import { SchematicTracePipelineSolver } from "lib/solvers/SchematicTracePipelineSolver/SchematicTracePipelineSolver"
+import "tests/fixtures/matcher"
+import inputProblem from "../bug-reports/bug-report-20260707T230831Z/bug-report-20260707T230831Z.json"
+
+// Reproduction for https://github.com/tscircuit/schematic-trace-solver/issues/655
+//
+// A net label must never render on top of a chip body — it ends up drawn
+// behind the component and is illegible. On this board the final placement
+// leaves four net labels 100% inside chip bodies:
+//
+//   VIN                  inside schematic_component_0 (U1)
+//   U1.FB to R2.pin1     inside schematic_component_4 (R1)
+//   PG                   inside schematic_component_0 (U1)
+//   VOUT                 inside schematic_component_6 (R3)
+//
+// NetLabelNetLabelCollisionSolver only relocates a label when it overlaps
+// *another label* (findNextCollidingPair looks for label-label overlaps).
+// A label sitting inside a chip without a label-label collision is never
+// checked against chips or moved out. Additionally, several chips on this
+// board overlap each other, so a pin can be covered by another chip's body —
+// port-only labels anchored on such pins collide in every orientation.
+//
+// This test pins the CURRENT (buggy) behavior so the bug is tracked by CI.
+// A fix should flip the assertion to .toEqual([]).
+test("repro #655: net labels are placed inside chip bodies", () => {
+  const solver = new SchematicTracePipelineSolver(inputProblem as any)
+  solver.solve()
+
+  const labels =
+    solver.netLabelNetLabelCollisionSolver!.getOutput().netLabelPlacements
+  const chips = solver.inputProblem.chips
+
+  const rectBounds = (
+    center: { x: number; y: number },
+    width: number,
+    height: number,
+  ) => ({
+    minX: center.x - width / 2,
+    maxX: center.x + width / 2,
+    minY: center.y - height / 2,
+    maxY: center.y + height / 2,
+  })
+
+  const overlapArea = (
+    a: { minX: number; maxX: number; minY: number; maxY: number },
+    b: { minX: number; maxX: number; minY: number; maxY: number },
+  ) => {
+    const ox = Math.min(a.maxX, b.maxX) - Math.max(a.minX, b.minX)
+    const oy = Math.min(a.maxY, b.maxY) - Math.max(a.minY, b.minY)
+    return ox > 0 && oy > 0 ? ox * oy : 0
+  }
+
+  const labelsInsideChips = labels.filter((label) => {
+    const labelBounds = rectBounds(label.center, label.width, label.height)
+    const labelArea = label.width * label.height
+    return chips.some(
+      (chip) =>
+        overlapArea(
+          labelBounds,
+          rectBounds(chip.center, chip.width, chip.height),
+        ) >
+        labelArea * 0.5,
+    )
+  })
+
+  // BUG: four labels render fully inside chip bodies
+  expect(labelsInsideChips.map((label) => label.netId).sort()).toEqual([
+    "PG",
+    "U1.FB to R2.pin1",
+    "VIN",
+    "VOUT",
+  ])
+})