feat(web): added testing structure

packages/web/package.json

@@ -36,7 +36,17 @@
   ],
   "scripts": {
     "build": "tsc --project tsconfig.build.json",
-    "prepublishOnly": "npm run build"
+    "prepublishOnly": "npm run build",
+    "dev": "vitest --watch",
+    "test": "vitest run",
+    "test:ui": "vitest --ui",
+    "test:coverage": "vitest run --coverage"
+  },
+  "devDependencies": {
+    "vitest": "^2.0.0",
+    "@vitest/ui": "^2.0.0",
+    "jsdom": "^24.0.0",
+    "vite": "^6.3.5"
   },
   "peerDependencies": {
     "typescript": ">=4.5.0"

packages/web/tests/setup.ts

@@ -0,0 +1,30 @@
+import { vi } from "vitest";
+
+// Mock Web Serial API
+const mockSerialPort = {
+  readable: new ReadableStream(),
+  writable: new WritableStream(),
+  close: vi.fn(),
+  forget: vi.fn(),
+  getInfo: vi.fn(() => ({ usbVendorId: 0x1234, usbProductId: 0x5678 })),
+};
+
+const mockSerial = {
+  requestPort: vi.fn(() => Promise.resolve(mockSerialPort)),
+  getPorts: vi.fn(() => Promise.resolve([mockSerialPort])),
+};
+
+// Mock WebUSB API
+const mockUSB = {
+  requestDevice: vi.fn(),
+  getDevices: vi.fn(() => Promise.resolve([])),
+};
+
+// Attach to global navigator
+Object.defineProperty(globalThis, "navigator", {
+  value: {
+    ...globalThis.navigator,
+    serial: mockSerial,
+    usb: mockUSB,
+  },
+});

packages/web/tests/utils/browser-support.test.ts

@@ -0,0 +1,35 @@
+import { describe, it, expect } from "vitest";
+import {
+  isWebSerialSupported,
+  isWebUSBSupported,
+} from "../../src/utils/browser-support.js";
+
+describe("browser-support", () => {
+  it("should detect Web Serial API support", () => {
+    expect(isWebSerialSupported()).toBe(true);
+  });
+
+  it("should detect WebUSB API support", () => {
+    expect(isWebUSBSupported()).toBe(true);
+  });
+
+  it("should handle missing Web Serial API gracefully", () => {
+    const originalSerial = globalThis.navigator.serial;
+    delete (globalThis.navigator as any).serial;
+
+    expect(isWebSerialSupported()).toBe(false);
+
+    // Restore
+    globalThis.navigator.serial = originalSerial;
+  });
+
+  it("should handle missing WebUSB API gracefully", () => {
+    const originalUSB = globalThis.navigator.usb;
+    delete (globalThis.navigator as any).usb;
+
+    expect(isWebUSBSupported()).toBe(false);
+
+    // Restore
+    globalThis.navigator.usb = originalUSB;
+  });
+});

packages/web/tests/utils/sign-magnitude.test.ts

@@ -0,0 +1,44 @@
+import { describe, it, expect } from "vitest";
+import {
+  encodeSignMagnitude,
+  decodeSignMagnitude,
+} from "../../src/utils/sign-magnitude.js";
+
+describe("sign-magnitude encoding", () => {
+  it("should encode positive values correctly", () => {
+    expect(encodeSignMagnitude(100)).toBe(100);
+    expect(encodeSignMagnitude(2047)).toBe(2047);
+    expect(encodeSignMagnitude(0)).toBe(0);
+  });
+
+  it("should encode negative values correctly", () => {
+    expect(encodeSignMagnitude(-100)).toBe(0x800 | 100); // Set sign bit (bit 11)
+    expect(encodeSignMagnitude(-2047)).toBe(0x800 | 2047);
+    expect(encodeSignMagnitude(-1)).toBe(0x800 | 1);
+  });
+
+  it("should decode back to original values", () => {
+    const testValues = [0, 1, 100, -100, 2047, -2047, -1];
+
+    testValues.forEach((value) => {
+      const encoded = encodeSignMagnitude(value);
+      const decoded = decodeSignMagnitude(encoded);
+      expect(decoded).toBe(value);
+    });
+  });
+
+  it("should throw on magnitude overflow", () => {
+    expect(() => encodeSignMagnitude(2048)).toThrow();
+    expect(() => encodeSignMagnitude(-2048)).toThrow();
+  });
+
+  it("should handle edge cases", () => {
+    // Test maximum positive value
+    expect(encodeSignMagnitude(2047)).toBe(2047);
+    expect(decodeSignMagnitude(2047)).toBe(2047);
+
+    // Test maximum negative value
+    expect(encodeSignMagnitude(-2047)).toBe(0x800 | 2047);
+    expect(decodeSignMagnitude(0x800 | 2047)).toBe(-2047);
+  });
+});

packages/web/vite.config.ts

@@ -0,0 +1,18 @@
+import { defineConfig } from "vitest/config";
+
+export default defineConfig({
+  test: {
+    environment: "jsdom",
+    globals: true,
+    setupFiles: ["./tests/setup.ts"],
+  },
+  build: {
+    lib: {
+      entry: "./src/index.ts",
+      formats: ["es"],
+    },
+    rollupOptions: {
+      external: ["typescript"],
+    },
+  },
+});