feat(tooltip): tests and code conformance

2nd-gen/packages/core/components/tooltip/Tooltip.base.ts

@@ -248,6 +248,13 @@ export abstract class TooltipBase extends SpectrumElement {
     this.dispatchAfterEvent(this.open);
   };
 
+  // Allows Escape behavior to be testable, does not interfere with native popover dismissal
+  private readonly handleKeyDown = (event: KeyboardEvent): void => {
+    if (event.key === 'Escape' && this.open) {
+      this.open = false;
+    }
+  };
+
   protected override updated(changedProperties: PropertyValues): void {
     super.updated(changedProperties);
     if (changedProperties.has('open')) {
@@ -269,12 +276,14 @@ export abstract class TooltipBase extends SpectrumElement {
     this.addEventListener('beforetoggle', this.handleBeforeToggle);
     this.addEventListener('toggle', this.handleToggle);
     this.addEventListener('transitionend', this.handleTransitionEnd);
+    document.addEventListener('keydown', this.handleKeyDown);
   }
 
   public override disconnectedCallback(): void {
     super.disconnectedCallback();
     this.removeEventListener('beforetoggle', this.handleBeforeToggle);
     this.removeEventListener('toggle', this.handleToggle);
     this.removeEventListener('transitionend', this.handleTransitionEnd);
+    document.removeEventListener('keydown', this.handleKeyDown);
   }
 }

2nd-gen/packages/swc/.storybook/preview.ts

@@ -248,6 +248,7 @@ const preview = {
               'Tools vs packages',
               'Writing migration guides',
               'Focus management',
+              'Changelog strategy',
             ],
             'Style guide',
             [
@@ -390,6 +391,11 @@ const preview = {
                 ['Rendering and styling migration analysis'],
                 'Field label',
                 ['Rendering and styling migration analysis'],
+                'Grid',
+                [
+                  'Accessibility migration analysis',
+                  'Rendering and styling migration analysis',
+                ],
                 'Help text',
                 ['Rendering and styling migration analysis'],
                 'Illustrated message',
@@ -436,6 +442,7 @@ const preview = {
                 'Popover',
                 [
                   'Accessibility migration analysis',
+                  'Migration plan',
                   'Rendering and styling migration analysis',
                 ],
                 'Progress bar',

2nd-gen/packages/swc/components/tooltip/Tooltip.ts

@@ -28,6 +28,11 @@ import styles from './tooltip.css';
  * @slot - Text label displayed in the tooltip.
  *
  * @cssprop --swc-tooltip-background-color - Background color of the tooltip bubble. Defaults to the neutral background color token.
+ *
+ * @fires swc-open - Dispatched when the tooltip begins to open, before the transition plays.
+ * @fires swc-close - Dispatched when the tooltip begins to close, before the transition plays.
+ * @fires swc-after-open - Dispatched after the tooltip finishes opening, once the transition completes.
+ * @fires swc-after-close - Dispatched after the tooltip finishes closing, once the transition completes.
  */
 export class Tooltip extends TooltipBase {
   // ──────────────────────────────

2nd-gen/packages/swc/components/tooltip/stories/tooltip.stories.ts

@@ -27,9 +27,9 @@ import {
 import '@adobe/spectrum-wc/components/button/swc-button.js';
 import '@adobe/spectrum-wc/components/tooltip/swc-tooltip.js';
 
-// ────────────────────
-//    METADATA SETUP
-// ────────────────────
+// ────────────────
+//    METADATA
+// ────────────────
 
 const { args, argTypes, template } = getStorybookHelpers('swc-tooltip');
 

2nd-gen/packages/swc/components/tooltip/test/tooltip.a11y.spec.ts

@@ -0,0 +1,158 @@
+/**
+ * Copyright 2026 Adobe. All rights reserved.
+ * This file is licensed to you 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 REPRESENTATIONS
+ * OF ANY KIND, either express or implied. See the License for the specific language
+ * governing permissions and limitations under the License.
+ */
+
+import { expect, test } from '@playwright/test';
+
+import { gotoStory } from '../../../utils/a11y-helpers.js';
+
+/**
+ * Accessibility tests for Tooltip component (2nd Generation)
+ *
+ * ARIA snapshot tests validate the accessibility tree structure.
+ * aXe WCAG compliance and color contrast validation are run via
+ * test-storybook (see .storybook/test-runner.ts). Both are included
+ * in the `test:a11y` command.
+ */
+
+test.describe('Tooltip - ARIA Snapshots', () => {
+  test('closed tooltip is hidden from accessibility tree', async ({ page }) => {
+    const root = await gotoStory(
+      page,
+      'components-tooltip--overview',
+      'swc-button'
+    );
+    // The trigger button is accessible; the closed popover is hidden from the tree.
+    await expect(root).toMatchAriaSnapshot(`
+      - button "Open"
+    `);
+  });
+
+  test('open tooltip exposes role="tooltip" in accessibility tree', async ({
+    page,
+  }) => {
+    await gotoStory(page, 'components-tooltip--overview', 'swc-button');
+
+    // Open the tooltip programmatically (HoverController not yet wired).
+    await page.evaluate(() => {
+      const tooltip = document.querySelector('swc-tooltip') as HTMLElement & {
+        open: boolean;
+      };
+      if (tooltip) {
+        tooltip.open = true;
+      }
+    });
+
+    // Wait for the popover to appear in the top layer.
+    await page.waitForFunction(() =>
+      document.querySelector('swc-tooltip')?.matches(':popover-open')
+    );
+
+    const root = page.locator('#storybook-root');
+    await expect(root).toMatchAriaSnapshot(`
+      - button "Open"
+      - tooltip "Save your changes"
+    `);
+  });
+
+  test('tooltip is removed from accessibility tree when closed', async ({
+    page,
+  }) => {
+    await gotoStory(page, 'components-tooltip--overview', 'swc-button');
+
+    // Open then close via the property.
+    await page.evaluate(() => {
+      const tooltip = document.querySelector('swc-tooltip') as HTMLElement & {
+        open: boolean;
+      };
+      if (tooltip) {
+        tooltip.open = true;
+      }
+    });
+    await page.waitForFunction(() =>
+      document.querySelector('swc-tooltip')?.matches(':popover-open')
+    );
+
+    await page.evaluate(() => {
+      const tooltip = document.querySelector('swc-tooltip') as HTMLElement & {
+        open: boolean;
+      };
+      if (tooltip) {
+        tooltip.open = false;
+      }
+    });
+    await page.waitForFunction(
+      () => !document.querySelector('swc-tooltip')?.matches(':popover-open')
+    );
+
+    const root = page.locator('#storybook-root');
+    await expect(root).toMatchAriaSnapshot(`
+      - button "Open"
+    `);
+  });
+
+  test('Escape closes an open tooltip', async ({ page }) => {
+    await gotoStory(page, 'components-tooltip--overview', 'swc-button');
+
+    await page.evaluate(() => {
+      const tooltip = document.querySelector('swc-tooltip') as HTMLElement & {
+        open: boolean;
+      };
+      if (tooltip) {
+        tooltip.open = true;
+      }
+    });
+    await page.waitForFunction(() =>
+      document.querySelector('swc-tooltip')?.matches(':popover-open')
+    );
+
+    await page.keyboard.press('Escape');
+
+    await page.waitForFunction(
+      () => !document.querySelector('swc-tooltip')?.matches(':popover-open')
+    );
+
+    const open = await page.evaluate(
+      () => (document.querySelector('swc-tooltip') as { open?: boolean })?.open
+    );
+    expect(open, 'tooltip.open is false after Escape').toBe(false);
+  });
+
+  test('all variant triggers are accessible', async ({ page }) => {
+    const root = await gotoStory(
+      page,
+      'components-tooltip--variants',
+      'swc-button'
+    );
+    await expect(root).toMatchAriaSnapshot(`
+      - button "Save"
+      - button "Upload"
+      - button "Delete"
+    `);
+  });
+
+  test('all placement triggers are accessible', async ({ page }) => {
+    const root = await gotoStory(
+      page,
+      'components-tooltip--placements',
+      'swc-button'
+    );
+    // Each placement renders a separate trigger button.
+    await expect(root).toMatchAriaSnapshot(`
+      - button "top"
+      - button "right"
+      - button "end"
+      - button "bottom"
+      - button "left"
+      - button "start"
+    `);
+  });
+});