Access-Control-Allow-Private-Network in CORS middleware tests

middleware/cors/cors_test.go

@@ -689,6 +689,43 @@ func Test_CORS_AllowCredentials(t *testing.T) {
 	}
 }
 
+// The Enhancement for issue #2804
+func Test_CORS_AllowPrivateNetworkAccess(t *testing.T) {
+	t.Parallel()
+
+	// Test scenario where AllowPrivateNetworkAccess is enabled
+	app := fiber.New()
+	app.Use(New(Config{
+		AllowPrivateNetworkAccess: true,
+	}))
+
+	handler := app.Handler()
+
+	ctx := &fasthttp.RequestCtx{}
+	ctx.Request.Header.SetMethod(fiber.MethodOptions)
+	ctx.Request.Header.Set(fiber.HeaderOrigin, "https://example.com")
+	ctx.Request.Header.Set("Access-Control-Request-Private-Network", "true")
+	handler(ctx)
+
+	// Verify the Access-Control-Allow-Private-Network header is set to "true"
+	require.Equal(t, "true", string(ctx.Response.Header.Peek("Access-Control-Allow-Private-Network")), "The Access-Control-Allow-Private-Network header should be set to 'true' when AllowPrivateNetworkAccess is enabled")
+
+	// Reset ctx for next test
+	ctx = &fasthttp.RequestCtx{}
+	ctx.Request.Header.SetMethod(fiber.MethodOptions)
+	ctx.Request.Header.Set(fiber.HeaderOrigin, "https://example.com")
+
+	// Test scenario where AllowPrivateNetworkAccess is disabled (default)
+	app = fiber.New()
+	app.Use(New())
+
+	handler = app.Handler()
+	handler(ctx)
+
+	// Verify the Access-Control-Allow-Private-Network header is not present
+	require.Equal(t, "", string(ctx.Response.Header.Peek("Access-Control-Allow-Private-Network")), "The Access-Control-Allow-Private-Network header should not be present by default")
+}
+
 // go test -v -run=^$ -bench=Benchmark_CORS_NewHandler -benchmem -count=4
 func Benchmark_CORS_NewHandler(b *testing.B) {
 	app := fiber.New()