Refactored polls module into layered architecture with typed domain objects, isolated SSE handling, and comprehensive tests.

owlbot/builtin_modules/polls/static/shared/dom.js

@@ -0,0 +1,52 @@
+// Copyright 2026 Logan Fick
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+export function requireElement(root, selector, elementType = Element) {
+    const element = root.querySelector(selector);
+    if (element === null) {
+        throw new Error(`Missing required element: ${selector}`);
+    }
+    if (!(element instanceof elementType)) {
+        throw new Error(`Element ${selector} is not a ${elementType.name}`);
+    }
+    return element;
+}
+
+export function createTextElement(tagName, className, text) {
+    const element = document.createElement(tagName);
+    if (className) {
+        element.className = className;
+    }
+    element.textContent = text;
+    return element;
+}
+
+export function setHidden(element, hidden) {
+    element.classList.toggle("d-none", hidden);
+}
+
+export function showAlert(container, message, variant = "danger") {
+    const alert = document.createElement("div");
+    alert.className = `alert alert-${variant} mb-0`;
+    alert.setAttribute("role", "alert");
+    alert.textContent = message;
+
+    container.replaceChildren(alert);
+}
+
+export function disableControls(root) {
+    for (const control of root.querySelectorAll("button, input, select, textarea")) {
+        control.disabled = true;
+    }
+}