1 files changed, 74 insertions, 0 deletions
diff --git a/browser/base/content/test/tabs/browser_tab_a11y_description.js b/browser/base/content/test/tabs/browser_tab_a11y_description.js
new file mode 100644
index 0000000000..04f9a54a1b
--- /dev/null
+++ b/browser/base/content/test/tabs/browser_tab_a11y_description.js
@@ -0,0 +1,74 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+
+async function waitForFocusAfterKey(ariaFocus, element, key, accel = false) {
+  let event = ariaFocus ? "AriaFocus" : "focus";
+  let friendlyKey = key;
+  if (accel) {
+    friendlyKey = "Accel+" + key;
+  }
+  key = "KEY_" + key;
+  let focused = BrowserTestUtils.waitForEvent(element, event);
+  EventUtils.synthesizeKey(key, { accelKey: accel });
+  await focused;
+  ok(true, element.label + " got " + event + " after " + friendlyKey);
+}
+
+function getA11yDescription(element) {
+  let descId = element.getAttribute("aria-describedby");
+  if (!descId) {
+    return null;
+  }
+  let descElem = document.getElementById(descId);
+  if (!descElem) {
+    return null;
+  }
+  return descElem.textContent;
+}
+
+add_task(async function testTabA11yDescription() {
+  const tab1 = await addTab("http://mochi.test:8888/1", { userContextId: 1 });
+  tab1.label = "tab1";
+  const context1 = ContextualIdentityService.getUserContextLabel(1);
+  const tab2 = await addTab("http://mochi.test:8888/2", { userContextId: 2 });
+  tab2.label = "tab2";
+  const context2 = ContextualIdentityService.getUserContextLabel(2);
+
+  await BrowserTestUtils.switchTab(gBrowser, tab1);
+  let focused = BrowserTestUtils.waitForEvent(tab1, "focus");
+  tab1.focus();
+  await focused;
+  ok(true, "tab1 initially focused");
+  ok(
+    getA11yDescription(tab1).endsWith(context1),
+    "tab1 has correct a11y description"
+  );
+  ok(!getA11yDescription(tab2), "tab2 has no a11y description");
+
+  info("Moving DOM focus to tab2");
+  await waitForFocusAfterKey(false, tab2, "ArrowRight");
+  ok(
+    getA11yDescription(tab2).endsWith(context2),
+    "tab2 has correct a11y description"
+  );
+  ok(!getA11yDescription(tab1), "tab1 has no a11y description");
+
+  info("Moving ARIA focus to tab1");
+  await waitForFocusAfterKey(true, tab1, "ArrowLeft", true);
+  ok(
+    getA11yDescription(tab1).endsWith(context1),
+    "tab1 has correct a11y description"
+  );
+  ok(!getA11yDescription(tab2), "tab2 has no a11y description");
+
+  info("Removing ARIA focus (reverting to DOM focus)");
+  await waitForFocusAfterKey(true, tab2, "ArrowRight");
+  ok(
+    getA11yDescription(tab2).endsWith(context2),
+    "tab2 has correct a11y description"
+  );
+  ok(!getA11yDescription(tab1), "tab1 has no a11y description");
+
+  BrowserTestUtils.removeTab(tab1);
+  BrowserTestUtils.removeTab(tab2);
+});