1 files changed, 62 insertions, 0 deletions
diff --git a/devtools/client/inspector/rules/test/browser_rules_mathml-element.js b/devtools/client/inspector/rules/test/browser_rules_mathml-element.js
new file mode 100644
index 0000000000..275426b105
--- /dev/null
+++ b/devtools/client/inspector/rules/test/browser_rules_mathml-element.js
@@ -0,0 +1,62 @@
+/* Any copyright is dedicated to the Public Domain.
+ http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+// Tests that the rule-view displays correctly on MathML elements.
+
+const TEST_URI = `
+  <div>
+    <math xmlns=\http://www.w3.org/1998/Math/MathML\>
+      <mfrac>
+        <msubsup>
+          <mi>a</mi>
+          <mi>i</mi>
+          <mi>j</mi>
+        </msubsup>
+        <msub>
+          <mi>x</mi>
+          <mn>0</mn>
+        </msub>
+      </mfrac>
+    </math>
+  </div>
+`;
+
+add_task(async function () {
+  await addTab("data:text/html;charset=utf-8," + encodeURIComponent(TEST_URI));
+  const { inspector, view } = await openRuleView();
+
+  info("Select the DIV node and verify the rule-view shows rules");
+  await selectNode("div", inspector);
+  ok(
+    view.element.querySelectorAll(".ruleview-rule").length,
+    "The rule-view shows rules for the div element"
+  );
+
+  info("Select various MathML nodes and verify the rule-view is empty");
+  await selectNode("math", inspector);
+  ok(
+    !view.element.querySelectorAll(".ruleview-rule").length,
+    "The rule-view is empty for the math element"
+  );
+
+  await selectNode("msubsup", inspector);
+  ok(
+    !view.element.querySelectorAll(".ruleview-rule").length,
+    "The rule-view is empty for the msubsup element"
+  );
+
+  await selectNode("mn", inspector);
+  ok(
+    !view.element.querySelectorAll(".ruleview-rule").length,
+    "The rule-view is empty for the mn element"
+  );
+
+  info("Select again the DIV node and verify the rule-view shows rules");
+  await selectNode("div", inspector);
+  ok(
+    view.element.querySelectorAll(".ruleview-rule").length,
+    "The rule-view shows rules for the div element"
+  );
+});