1 files changed, 43 insertions, 0 deletions
diff --git a/devtools/client/inspector/rules/test/browser_rules_add-rule-and-remove-style-node.js b/devtools/client/inspector/rules/test/browser_rules_add-rule-and-remove-style-node.js
new file mode 100644
index 0000000000..1505f70c32
--- /dev/null
+++ b/devtools/client/inspector/rules/test/browser_rules_add-rule-and-remove-style-node.js
@@ -0,0 +1,43 @@
+/* Any copyright is dedicated to the Public Domain.
+ http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+// Tests that bug 1736412 is fixed
+// We press "add new rule", then we remove the style node
+// We then try to press "add new rule again"
+
+const TEST_URI = '<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 selectNode("#testid", inspector);
+  await addNewRule(inspector, view);
+  await testNewRule(view, 1);
+  await testRemoveStyleNode();
+  await addNewRule(inspector, view);
+  await testNewRule(view, 1);
+});
+
+function testNewRule(view) {
+  const ruleEditor = getRuleViewRuleEditor(view, 1);
+  const editor = ruleEditor.selectorText.ownerDocument.activeElement;
+  is(editor.value, "#testid", "Selector editor value is as expected");
+  info("Escaping from the selector field the change");
+  EventUtils.synthesizeKey("KEY_Escape");
+}
+
+async function testRemoveStyleNode() {
+  info("Removing the style node from the dom");
+  const nbStyleSheets = await SpecialPowers.spawn(
+    gBrowser.selectedBrowser,
+    [],
+    () => {
+      content.document.styleSheets[0].ownerNode.remove();
+      return content.document.styleSheets.length;
+    }
+  );
+  is(nbStyleSheets, 0, "Style node has been removed");
+}