fix(tooltip): fix infinite loop in self-managed tooltips (#4269)

* fix(tooltip): fix infinite loop in self-managed tooltips

* chore: return null instead of document when no trigger is found

* chore: add a unit test to verify that event listeners are no longer attached to document

* chore: update tests to verify against triggerElement

---------

Co-authored-by: rmanole <rmanole@adobe.com>

packages/tooltip/src/Tooltip.ts

@@ -205,12 +205,12 @@ export class Tooltip extends SpectrumElement {
         );
     }
 
-    private get triggerElement(): HTMLElement {
+    private get triggerElement(): HTMLElement | null {
         // Resolve the parent element of the assigned slot (if one exists) or of the Tooltip.
         let start: HTMLElement = this.assignedSlot || this;
         let root = start.getRootNode();
-        if (window.__swc.DEBUG) {
-            if (root === document) {
+        if (root === document) {
+            if (window.__swc.DEBUG) {
                 window.__swc.warn(
                     this,
                     `Self managed <${this.localName}> elements walk up the composed tree to acquire a trigger element. No trigger element was found before the document.`,
@@ -219,8 +219,8 @@ export class Tooltip extends SpectrumElement {
                         level: 'high',
                     }
                 );
-                return root as HTMLElement;
             }
+            return null;
         }
         let triggerElement = (start.parentElement ||
             (root as ShadowRoot).host ||
@@ -231,8 +231,8 @@ export class Tooltip extends SpectrumElement {
                 triggerElement.assignedSlot || (triggerElement as HTMLElement);
             root = start.getRootNode();
             /* c8 ignore next 13 */
-            if (window.__swc.DEBUG) {
-                if (root === document) {
+            if (root === document) {
+                if (window.__swc.DEBUG) {
                     window.__swc.warn(
                         this,
                         `Self managed <${this.localName}> elements walk up the composed tree to acquire a trigger element. No trigger element was found before the document.`,
@@ -241,8 +241,8 @@ export class Tooltip extends SpectrumElement {
                             level: 'high',
                         }
                     );
-                    return root as HTMLElement;
                 }
+                return null;
             }
             triggerElement = (start.parentElement ||
                 (root as ShadowRoot).host ||

packages/tooltip/test/tooltip.test.ts

@@ -22,7 +22,7 @@ import {
 } from '@open-wc/testing';
 import { Button } from '@spectrum-web-components/button';
 import '@spectrum-web-components/button/sp-button.js';
-import { stub } from 'sinon';
+import { spy, stub } from 'sinon';
 import { testForLitDevWarnings } from '../../../test/testing-helpers.js';
 import { sendMouse } from '../../../test/plugins/browser.js';
 
@@ -214,6 +214,20 @@ describe('Tooltip', () => {
 
         expect(typeof el.tipElement).to.not.equal('undefined');
     });
+
+    it('self managed does not attach event listeners if no trigger was found', async () => {
+        const documentEventsSpy = spy(document, 'addEventListener');
+        const el = await fixture<Tooltip>(
+            html`
+                <sp-tooltip self-managed>Help text.</sp-tooltip>
+            `
+        );
+
+        await elementUpdated(el);
+        expect(documentEventsSpy.callCount).to.equal(0);
+        expect(el.overlayElement?.triggerElement).to.be.null;
+        documentEventsSpy.restore();
+    });
     describe('dev mode', () => {
         let consoleWarnStub!: ReturnType<typeof stub>;
         before(() => {