1 files changed, 31 insertions, 0 deletions
diff --git a/devtools/client/inspector/rules/test/browser_rules_lineNumbers.js b/devtools/client/inspector/rules/test/browser_rules_lineNumbers.js
new file mode 100644
index 0000000000..9c9d1ef9ab
--- /dev/null
+++ b/devtools/client/inspector/rules/test/browser_rules_lineNumbers.js
@@ -0,0 +1,31 @@
+/* Any copyright is dedicated to the Public Domain.
+ http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+// Test that editing a rule will update the line numbers of subsequent
+// rules in the rule view.
+
+const TESTCASE_URI = URL_ROOT + "doc_ruleLineNumbers.html";
+
+add_task(async function () {
+  await addTab(TESTCASE_URI);
+  const { inspector, view } = await openRuleView();
+  await selectNode("#testid", inspector);
+
+  const bodyRuleEditor = getRuleViewRuleEditor(view, 3);
+  const value = getRuleViewLinkTextByIndex(view, 2);
+  // Note that this is relative to the <style>.
+  is(value.slice(-2), ":6", "initial rule line number is 6");
+
+  const onLocationChanged = once(
+    bodyRuleEditor.rule.domRule,
+    "location-changed"
+  );
+  await addProperty(view, 1, "font-size", "23px");
+  await onLocationChanged;
+
+  const newBodyTitle = getRuleViewLinkTextByIndex(view, 2);
+  // Note that this is relative to the <style>.
+  is(newBodyTitle.slice(-2), ":7", "updated rule line number is 7");
+});