Add capacitive touch slider snapshot test

tests/capacitive-touch-slider.test.tsx

@@ -0,0 +1,106 @@
+import { test, expect } from "bun:test"
+import { Circuit } from "../lib/Circuit"
+
+// Capacitive Touch Slider Test
+// This test demonstrates polygon smtpads with solder mask for capacitive touch
+
+test("capacitive touch slider with polygon smtpads and solder mask", () => {
+  const circuit = new Circuit()
+
+  circuit.add(
+    <board width="30mm" height="10mm">
+      {/* Capacitive touch slider with 5 segments */}
+      <group>
+        {/* Segment 1 */}
+        <smtpad
+          name="slider_1"
+          shape="polygon"
+          points={[
+            { x: 0, y: 0 },
+            { x: 5, y: 0 },
+            { x: 5, y: 8 },
+            { x: 0, y: 8 },
+          ]}
+          layer="top"
+          coveredWithSolderMask={true}
+          solderMaskMargin={0.1}
+        />
+        {/* Segment 2 */}
+        <smtpad
+          name="slider_2"
+          shape="polygon"
+          points={[
+            { x: 5.5, y: 0 },
+            { x: 10.5, y: 0 },
+            { x: 10.5, y: 8 },
+            { x: 5.5, y: 8 },
+          ]}
+          layer="top"
+          coveredWithSolderMask={true}
+          solderMaskMargin={0.1}
+        />
+        {/* Segment 3 */}
+        <smtpad
+          name="slider_3"
+          shape="polygon"
+          points={[
+            { x: 11, y: 0 },
+            { x: 16, y: 0 },
+            { x: 16, y: 8 },
+            { x: 11, y: 8 },
+          ]}
+          layer="top"
+          coveredWithSolderMask={true}
+          solderMaskMargin={0.1}
+        />
+        {/* Segment 4 */}
+        <smtpad
+          name="slider_4"
+          shape="polygon"
+          points={[
+            { x: 16.5, y: 0 },
+            { x: 21.5, y: 0 },
+            { x: 21.5, y: 8 },
+            { x: 16.5, y: 8 },
+          ]}
+          layer="top"
+          coveredWithSolderMask={true}
+          solderMaskMargin={0.1}
+        />
+        {/* Segment 5 */}
+        <smtpad
+          name="slider_5"
+          shape="polygon"
+          points={[
+            { x: 22, y: 0 },
+            { x: 27, y: 0 },
+            { x: 27, y: 8 },
+            { x: 22, y: 8 },
+          ]}
+          layer="top"
+          coveredWithSolderMask={true}
+          solderMaskMargin={0.1}
+        />
+      </group>
+    </board>
+  )
+
+  circuit.render()
+
+  // Get PCB elements
+  const pcbElements = circuit.getCircuitJson()
+
+  // Check for smtpad elements
+  const smtpads = pcbElements.filter((el: any) => el.type === "pcb_smtpad")
+  expect(smtpads.length).toBe(5)
+
+  // Check that all smtpads have coveredWithSolderMask
+  for (const smtpad of smtpads) {
+    expect(smtpad.shape).toBe("polygon")
+    expect(smtpad.is_covered_with_solder_mask).toBe(true)
+    expect(smtpad.soldermask_margin).toBe(0.1)
+  }
+
+  // Generate snapshot for visual verification
+  expect(circuit.getCircuitJson()).toMatchSnapshot("capacitive-touch-slider")
+})