Project import generated by Copybara.
GitOrigin-RevId: d9e9e3fb4e31372ec1fb43b178994ca78fa8fe70
diff --git a/static_src/shared/dom-helpers.js b/static_src/shared/dom-helpers.js
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+// Copyright 2019 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+
+// Prevent triggering input change handlers on key events that don't
+// edit forms.
+export const NON_EDITING_KEY_EVENTS = new Set(['Enter', 'Tab', 'Escape',
+ 'ArrowUp', 'ArrowLeft', 'ArrowRight', 'ArrowDown']);
+const INPUT_TYPES_WITHOUT_TEXT_INPUT = [
+ 'checkbox',
+ 'radio',
+ 'file',
+ 'submit',
+ 'button',
+ 'image',
+];
+
+// TODO: Add a method to watch for property changes in one of a subset of
+// element properties.
+// Via: https://crrev.com/c/infra/infra/+/1762911/7/appengine/monorail/static_src/elements/help/mr-cue/mr-cue.js
+
+/**
+ * Checks if a keyboard event should be disabled when the user is typing.
+ *
+ * @param {HTMLElement} element is a dom node to run checks against.
+ * @return {boolean} Whether the dom node is an element that accepts key input.
+ */
+export function isTextInput(element) {
+ const tagName = element.tagName && element.tagName.toUpperCase();
+ if (tagName === 'INPUT') {
+ const type = element.type.toLowerCase();
+ if (INPUT_TYPES_WITHOUT_TEXT_INPUT.includes(type)) {
+ return false;
+ }
+ return true;
+ }
+ return tagName === 'SELECT' || tagName === 'TEXTAREA' ||
+ element.isContentEditable;
+}
+
+/**
+ * Helper to find the EventTarget that an Event originated from, even if that
+ * EventTarget is buried until multiple layers of ShadowDOM.
+ *
+ * @param {Event} event
+ * @return {EventTarget} The DOM node that the event came from. For example,
+ * if the input was a keypress, this might be the input element the user was
+ * typing into.
+ */
+export function findDeepEventTarget(event) {
+ /**
+ * Event.target finds the element the event came from, but only
+ * finds events that come from the highest ShadowDOM level. For
+ * example, an Event listener attached to "window" will have all
+ * Events originating from the SPA set to a target of <mr-app>.
+ */
+ const path = event.composedPath();
+ return path ? path[0] : event.target;
+}