1 files changed, 71 insertions, 0 deletions
diff --git a/devtools/client/inspector/markup/test/browser_markup_shadowdom_slotted_keyboard_focus.js b/devtools/client/inspector/markup/test/browser_markup_shadowdom_slotted_keyboard_focus.js
new file mode 100644
index 0000000000..86ee603f56
--- /dev/null
+++ b/devtools/client/inspector/markup/test/browser_markup_shadowdom_slotted_keyboard_focus.js
@@ -0,0 +1,71 @@
+/* Any copyright is dedicated to the Public Domain.
+ http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+// Test that cycling focus with keyboard (via TAB key) in slotted nodes works.
+
+const TEST_URL = `data:text/html;charset=utf-8,
+  <test-component>
+    <div slot="slot1" id="el1">slot1-1</div>
+  </test-component>
+
+  <script>
+    'use strict';
+    customElements.define('test-component', class extends HTMLElement {
+      constructor() {
+        super();
+        let shadowRoot = this.attachShadow({mode: 'open'});
+        shadowRoot.innerHTML = '<slot name="slot1"></slot>';
+      }
+    });
+  </script>`;
+
+add_task(async function () {
+  const { inspector } = await openInspectorForURL(TEST_URL);
+  const { markup } = inspector;
+  const win = inspector.markup.doc.defaultView;
+
+  info("Find and expand the test-component shadow DOM host.");
+  const hostFront = await getNodeFront("test-component", inspector);
+  const hostContainer = markup.getContainer(hostFront);
+  await expandContainer(inspector, hostContainer);
+
+  info("Expand the shadow root");
+  const shadowRootContainer = hostContainer.getChildContainers()[0];
+  await expandContainer(inspector, shadowRootContainer);
+
+  info("Expand the slot");
+  const slotContainer = shadowRootContainer.getChildContainers()[0];
+  await expandContainer(inspector, slotContainer);
+
+  info("Select the slotted container for the element");
+  const node = slotContainer.getChildContainers()[0].node;
+  const container = inspector.markup.getContainer(node, true);
+  await selectNode(node, inspector, "no-reason", true);
+
+  const root = inspector.markup.getContainer(inspector.markup._rootNode);
+  root.elt.focus();
+  const tagSpan = container.elt.querySelector(".tag");
+  const revealLink = container.elt.querySelector(".reveal-link");
+
+  info("Hit Enter to focus on the first element");
+  let tagFocused = once(tagSpan, "focus");
+  EventUtils.synthesizeAndWaitKey("KEY_Enter", {}, win);
+  await tagFocused;
+
+  info("Hit Tab to focus on the next element");
+  const linkFocused = once(revealLink, "focus");
+  EventUtils.synthesizeKey("KEY_Tab", {}, win);
+  await linkFocused;
+
+  info("Hit Tab again to cycle focus to the first element");
+  tagFocused = once(tagSpan, "focus");
+  EventUtils.synthesizeKey("KEY_Tab", {}, win);
+  await tagFocused;
+
+  ok(
+    inspector.markup.doc.activeElement === tagSpan,
+    "Focus has gone back to first element"
+  );
+});