1 files changed, 50 insertions, 0 deletions
diff --git a/devtools/client/inspector/rules/test/browser_rules_add-rule-button-state.js b/devtools/client/inspector/rules/test/browser_rules_add-rule-button-state.js
new file mode 100644
index 0000000000..578f50c5a8
--- /dev/null
+++ b/devtools/client/inspector/rules/test/browser_rules_add-rule-button-state.js
@@ -0,0 +1,50 @@
+/* Any copyright is dedicated to the Public Domain.
+ http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+// Tests if the `Add rule` button disables itself properly for non-element nodes
+// and anonymous element.
+
+const TEST_URI = `
+  <style type="text/css">
+    #pseudo::before {
+      content: "before";
+    }
+  </style>
+  <div id="pseudo"></div>
+  <div id="testid">Test Node</div>
+`;
+
+add_task(async function () {
+  await addTab("data:text/html;charset=utf-8," + encodeURIComponent(TEST_URI));
+  const { inspector, view } = await openRuleView();
+  await testDisabledButton(inspector, view);
+});
+
+async function testDisabledButton(inspector, view) {
+  const node = "#testid";
+
+  info("Selecting a real element");
+  await selectNode(node, inspector);
+  ok(!view.addRuleButton.disabled, "Add rule button should be enabled");
+
+  info("Select a null element");
+  await view.selectElement(null);
+  ok(view.addRuleButton.disabled, "Add rule button should be disabled");
+
+  info("Selecting a real element");
+  await selectNode(node, inspector);
+  ok(!view.addRuleButton.disabled, "Add rule button should be enabled");
+
+  info("Selecting a pseudo element");
+  const pseudo = await getNodeFront("#pseudo", inspector);
+  const children = await inspector.walker.children(pseudo);
+  const before = children.nodes[0];
+  await selectNode(before, inspector);
+  ok(view.addRuleButton.disabled, "Add rule button should be disabled");
+
+  info("Selecting a real element");
+  await selectNode(node, inspector);
+  ok(!view.addRuleButton.disabled, "Add rule button should be enabled");
+}