1 files changed, 72 insertions, 0 deletions
diff --git a/devtools/client/performance-new/test/browser/browser_aboutprofiling-interval.js b/devtools/client/performance-new/test/browser/browser_aboutprofiling-interval.js
new file mode 100644
index 0000000000..6dcc4e1156
--- /dev/null
+++ b/devtools/client/performance-new/test/browser/browser_aboutprofiling-interval.js
@@ -0,0 +1,72 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+"use strict";
+
+add_task(async function test() {
+  info("Test that about:profiling can modify the sampling interval.");
+
+  await withAboutProfiling(async document => {
+    const intervalInput = await getNearestInputFromText(
+      document,
+      "Sampling interval:"
+    );
+    is(
+      getActiveConfiguration().interval,
+      1,
+      "The active configuration's interval is set to a specific number initially."
+    );
+    is(
+      intervalInput.getAttribute("aria-valuemin"),
+      "0.01",
+      "aria-valuemin has the expected value"
+    );
+    is(
+      intervalInput.getAttribute("aria-valuemax"),
+      "100",
+      "aria-valuemax has the expected value"
+    );
+    is(
+      intervalInput.getAttribute("aria-valuenow"),
+      "1",
+      "aria-valuenow has the expected value"
+    );
+
+    info(
+      "Increase the interval by an arbitrary amount. The input range will " +
+        "scale that to the final value presented to the profiler."
+    );
+    setReactFriendlyInputValue(intervalInput, Number(intervalInput.value) + 1);
+
+    is(
+      getActiveConfiguration().interval,
+      2,
+      "The configuration's interval was able to be increased."
+    );
+    is(
+      intervalInput.getAttribute("aria-valuenow"),
+      "2",
+      "aria-valuenow has the expected value"
+    );
+
+    intervalInput.focus();
+
+    info("Increase the interval with the keyboard");
+    EventUtils.synthesizeKey("VK_RIGHT");
+    await waitUntil(() => getActiveConfiguration().interval === 3);
+    is(
+      intervalInput.getAttribute("aria-valuenow"),
+      "3",
+      "aria-valuenow has the expected value"
+    );
+
+    info("Decrease the interval with the keyboard");
+    EventUtils.synthesizeKey("VK_LEFT");
+    await waitUntil(() => getActiveConfiguration().interval === 2);
+    is(
+      intervalInput.getAttribute("aria-valuenow"),
+      "2",
+      "aria-valuenow has the expected value"
+    );
+  });
+});