chore(sonar): resolve maintainability findings (74 → 1)

client/src/components/features/parser-output.tsx

@@ -17,6 +17,7 @@ import { useState } from "react";
 import * as React from "react";
 import type { SeverityLevel } from "@shared/reserved-names-validator";
 import type { SourceLocation } from "@shared/source-project";
+import { isUnoPwmPin } from "@shared/utils/arduino-utils";
 import {
   formatSourceNavigationTarget,
   isSourceLocation,
@@ -28,7 +29,6 @@ import { TabBar } from "@/components/ui/tab-bar";
 import { getSeverityStatus, getStatusColor, getStatusTextClass } from "@/lib/status-semantics";
 
 // Module-level constants (not re-created on every render)
-const PWM_PINS = new Set([3, 5, 6, 9, 10, 11]);
 const ALL_PIN_RECORDS: IOPinRecord[] = Array.from({ length: 20 }, (_, pinId) => ({
   pin: pinId >= 14 ? `A${pinId - 14}` : String(pinId),
   pinId,
@@ -80,7 +80,7 @@ function getRxTxBadge(pin: string): JSX.Element | null {
 /** Returns a PWM tilde element for PWM-capable pins, or null. Fixes S1940 IIFE anti-pattern. */
 function getPwmTilde(pin: string): JSX.Element | null {
   const n = Number.parseInt(pin, 10);
-  return !Number.isNaN(n) && PWM_PINS.has(n)
+  return !Number.isNaN(n) && isUnoPwmPin(n)
     ? <span className="text-yellow-400">~</span>
     : null;
 }

client/src/hooks/usePinPollingEngine.ts

@@ -1,9 +1,9 @@
 import { useEffect } from "react";
 import type { PinState } from "@/components/features/arduino-board";
+import { UNO_PWM_PINS, isUnoPwmPin } from "@shared/utils/arduino-utils";
 
 // Constants
 const VIEWBOX_HEIGHT = 209;
-const PWM_PINS = [3, 5, 6, 9, 10, 11];
 const FADE_OUT_MS = 200;
 
 /**
@@ -240,7 +240,7 @@ function pinColorForState(state: PinState, pin: number, brightness: number): str
   if (brightness <= 0) return "var(--color-black)";
   const intensity = Math.round(brightness * 255);
   if (state.type === "digital") return `rgb(${intensity}, 0, 0)`;
-  if (PWM_PINS.includes(pin)) {
+  if (isUnoPwmPin(pin)) {
     const pwmIntensity = Math.round((state.value / 255) * intensity);
     return `rgb(${pwmIntensity}, 0, 0)`;
   }
@@ -391,7 +391,7 @@ export function usePinPollingEngine({
       return;
     }
 
-    for (const pin of PWM_PINS) {
+    for (const pin of UNO_PWM_PINS) {
       const valStr = getPinState(pin)?.value?.toString() ?? "";
       updateLabelForPin(svgEl, `pin-${pin}-state`, `pin-${pin}-frame`, `pin-${pin}-val`, valStr, showPWMValues);
     }

shared/parsers/hardware-compatibility-parser.ts

@@ -6,8 +6,8 @@ import {
   type StaticIOOperation,
   type UnresolvedStaticIOCall,
 } from "@shared/io-registry-parser";
+import { UNO_PWM_PINS, isUnoPwmPin } from "@shared/utils/arduino-utils";
 
-const PWM_PINS = new Set([3, 5, 6, 9, 10, 11]);
 const DIGITAL_OPERATIONS = new Set<StaticIOOperation>([
   "digitalRead",
   "digitalWrite",
@@ -93,13 +93,13 @@ export class HardwareCompatibilityParser {
 
   private checkAnalogWritePWM(): ParserMessage[] {
     return resolvedCalls(this.analysis, "analogWrite")
-      .filter(({ pinId }) => !PWM_PINS.has(pinId))
+      .filter(({ pinId }) => !isUnoPwmPin(pinId))
       .map((call) => ({
         id: randomUUID(),
         type: "warning" as const,
         category: "hardware" as const,
         severity: 2 as const,
-        message: `analogWrite(${call.sourceExpression}, ...) used on pin ${call.pinId}, which doesn't support PWM on Arduino UNO. PWM pins: 3, 5, 6, 9, 10, 11.`,
+        message: `analogWrite(${call.sourceExpression}, ...) used on pin ${call.pinId}, which doesn't support PWM on Arduino UNO. PWM pins: ${UNO_PWM_PINS.join(", ")}.`,
         suggestion: "// Use PWM pin instead: analogWrite(3, value);",
         ...sourceLocation(call),
       }));

shared/utils/arduino-utils.ts

@@ -9,3 +9,16 @@ const PIN_MODE_NAMES: Record<number, PinMode> = {
 export function pinModeToString(mode: number): PinMode {
   return PIN_MODE_NAMES[mode] ?? "INPUT"; // Default to INPUT for invalid modes
 }
+
+/**
+ * PWM-capable digital pins of the Arduino UNO (the pins marked "~"), in board
+ * order. The single definition of this hardware property: UI, polling engine
+ * and hardware-compatibility checks all derive from it.
+ */
+export const UNO_PWM_PINS: readonly number[] = [3, 5, 6, 9, 10, 11];
+
+const UNO_PWM_PIN_SET: ReadonlySet<number> = new Set(UNO_PWM_PINS);
+
+export function isUnoPwmPin(pin: number): boolean {
+  return UNO_PWM_PIN_SET.has(pin);
+}

tests/client/arduino-simulator-codechange.test.tsx

@@ -76,7 +76,7 @@ test("handles simulation_status message", async () => {
 
   // Sanity-check: hook exposes empty queue initially
   const wsMock = (await import("@/hooks/use-websocket")).useWebSocket();
-  expect(wsMock.messageQueue.length).toBe(0);
+  expect(wsMock.messageQueue).toHaveLength(0);
 
   // Push message AFTER mount and trigger re-render in act()
   await act(async () => {
@@ -98,11 +98,9 @@ test("handles simulation_status message", async () => {
     vi.runOnlyPendingTimers();
   });
 
-  // Test the assertion
-  await act(async () => {
-    await waitFor(() => {
-      expect(document.querySelector('[data-testid="sim-status"]')?.textContent).toBe("running");
-    });
+  // waitFor flushes its own updates; no surrounding act() needed
+  await waitFor(() => {
+    expect(document.querySelector('[data-testid="sim-status"]')?.textContent).toBe("running");
   });
 
   // Final timer flush

tests/client/font-scale-utils.test.ts

@@ -110,90 +110,34 @@ describe("Font Scale Utils", () => {
   });
 
   describe("increaseFontScale", () => {
-    it("should increase from S to M", () => {
-      setFontScale(0.875); // S
+    it.each([
+      { title: "should increase from S to M", from: 0.875, changed: true, to: 1.0 },
+      { title: "should increase from M to L", from: 1.0, changed: true, to: 1.125 },
+      { title: "should increase from L to XL", from: 1.125, changed: true, to: 1.25 },
+      { title: "should increase from XL to XXL", from: 1.25, changed: true, to: 1.5 },
+      { title: "should not increase beyond XXL", from: 1.5, changed: false, to: 1.5 },
+      { title: "should handle custom scale values (0.9 jumps to M)", from: 0.9, changed: true, to: 1.0 },
+    ])("$title", ({ from, changed, to }) => {
+      setFontScale(from);
       const result = increaseFontScale();
-      expect(result).toBe(true);
-      expect(getCurrentFontScale()).toBe(1.0); // M
-    });
-
-    it("should increase from M to L", () => {
-      setFontScale(1.0); // M
-      const result = increaseFontScale();
-      expect(result).toBe(true);
-      expect(getCurrentFontScale()).toBe(1.125); // L
-    });
-
-    it("should increase from L to XL", () => {
-      setFontScale(1.125); // L
-      const result = increaseFontScale();
-      expect(result).toBe(true);
-      expect(getCurrentFontScale()).toBe(1.25); // XL
-    });
-
-    it("should increase from XL to XXL", () => {
-      setFontScale(1.25); // XL
-      const result = increaseFontScale();
-      expect(result).toBe(true);
-      expect(getCurrentFontScale()).toBe(1.5); // XXL
-    });
-
-    it("should not increase beyond XXL", () => {
-      setFontScale(1.5); // XXL
-      const result = increaseFontScale();
-      expect(result).toBe(false);
-      expect(getCurrentFontScale()).toBe(1.5); // Still XXL
-    });
-
-    it("should handle custom scale values", () => {
-      setFontScale(0.9); // Between S and M
-      const result = increaseFontScale();
-      expect(result).toBe(true);
-      expect(getCurrentFontScale()).toBe(1.0); // Jumps to M
+      expect(result).toBe(changed);
+      expect(getCurrentFontScale()).toBe(to);
     });
   });
 
   describe("decreaseFontScale", () => {
-    it("should decrease from XXL to XL", () => {
-      setFontScale(1.5); // XXL
-      const result = decreaseFontScale();
-      expect(result).toBe(true);
-      expect(getCurrentFontScale()).toBe(1.25); // XL
-    });
-
-    it("should decrease from XL to L", () => {
-      setFontScale(1.25); // XL
-      const result = decreaseFontScale();
-      expect(result).toBe(true);
-      expect(getCurrentFontScale()).toBe(1.125); // L
-    });
-
-    it("should decrease from L to M", () => {
-      setFontScale(1.125); // L
-      const result = decreaseFontScale();
-      expect(result).toBe(true);
-      expect(getCurrentFontScale()).toBe(1.0); // M
-    });
-
-    it("should decrease from M to S", () => {
-      setFontScale(1.0); // M
-      const result = decreaseFontScale();
-      expect(result).toBe(true);
-      expect(getCurrentFontScale()).toBe(0.875); // S
-    });
-
-    it("should not decrease below S", () => {
-      setFontScale(0.875); // S
-      const result = decreaseFontScale();
-      expect(result).toBe(false);
-      expect(getCurrentFontScale()).toBe(0.875); // Still S
-    });
-
-    it("should handle custom scale values", () => {
-      setFontScale(1.1); // Between M and L
+    it.each([
+      { title: "should decrease from XXL to XL", from: 1.5, changed: true, to: 1.25 },
+      { title: "should decrease from XL to L", from: 1.25, changed: true, to: 1.125 },
+      { title: "should decrease from L to M", from: 1.125, changed: true, to: 1.0 },
+      { title: "should decrease from M to S", from: 1.0, changed: true, to: 0.875 },
+      { title: "should not decrease below S", from: 0.875, changed: false, to: 0.875 },
+      { title: "should handle custom scale values (1.1 jumps to M)", from: 1.1, changed: true, to: 1.0 },
+    ])("$title", ({ from, changed, to }) => {
+      setFontScale(from);
       const result = decreaseFontScale();
-      expect(result).toBe(true);
-      expect(getCurrentFontScale()).toBe(1.0); // Jumps to M
+      expect(result).toBe(changed);
+      expect(getCurrentFontScale()).toBe(to);
     });
   });
 

tests/client/hooks/use-backend-health.test.tsx

@@ -451,7 +451,7 @@ describe("useBackendHealth", () => {
     });
 
     // No new calls after unmount
-    expect(fetchSpy.mock.calls.length).toBe(callsBefore);
+    expect(fetchSpy.mock.calls).toHaveLength(callsBefore);
   });
 
   it("should not update state after unmount", async () => {

tests/client/hooks/use-toast.test.ts

@@ -57,7 +57,7 @@ describe("use-toast", () => {
       expect(t).toHaveProperty("update");
     });
 
-    expect(result.current.toasts.length).toBe(1);
+    expect(result.current.toasts).toHaveLength(1);
     expect(result.current.toasts[0].title).toBe("Hello");
     expect(result.current.toasts[0].open).toBe(true);
   });
@@ -87,7 +87,7 @@ describe("use-toast", () => {
     });
 
     // TOAST_LIMIT = 1, so only the newest toast should be present
-    expect(result.current.toasts.length).toBe(1);
+    expect(result.current.toasts).toHaveLength(1);
     expect(result.current.toasts[0].title).toBe("Second");
   });
 
@@ -138,7 +138,7 @@ describe("use-toast", () => {
       vi.advanceTimersByTime(4000);
     });
 
-    expect(result.current.toasts.length).toBe(0);
+    expect(result.current.toasts).toHaveLength(0);
   });
 
   it("dismiss without toastId dismisses all toasts", () => {
@@ -173,7 +173,7 @@ describe("use-toast", () => {
       vi.advanceTimersByTime(4000);
     });
 
-    expect(result.current.toasts.length).toBe(0);
+    expect(result.current.toasts).toHaveLength(0);
   });
 
   it("onOpenChange(false) triggers dismiss", () => {
@@ -255,6 +255,6 @@ describe("use-toast", () => {
       vi.advanceTimersByTime(4000);
     });
 
-    expect(result.current.toasts.length).toBe(0);
+    expect(result.current.toasts).toHaveLength(0);
   });
 });

tests/client/output-panel-auto-behavior.test.tsx

@@ -380,7 +380,7 @@ error: missing semicolon on line 5`;
       // Verify the condition logic
       expect(successCondition.lastCompilationResult).toBe("success");
       expect(successCondition.hasCompilationErrors).toBe(false);
-      expect(successCondition.parserMessages.length).toBe(0);
+      expect(successCondition.parserMessages).toHaveLength(0);
 
       // Panel should be minimized to 3%
       const shouldMinimize =

tests/client/output-panel.test.tsx

@@ -103,7 +103,7 @@ describe("OutputPanel — callback reference stability", () => {
     return new Promise<void>((resolve) => {
       requestAnimationFrame(() => {
         observer.disconnect();
-        expect(records.length).toBe(0);
+        expect(records).toHaveLength(0);
         resolve();
       });
     });