1 files changed, 55 insertions, 0 deletions
diff --git a/devtools/client/inspector/rules/test/browser_rules_flexbox-highlighter-on-mutation.js b/devtools/client/inspector/rules/test/browser_rules_flexbox-highlighter-on-mutation.js
new file mode 100644
index 0000000000..eb887f9848
--- /dev/null
+++ b/devtools/client/inspector/rules/test/browser_rules_flexbox-highlighter-on-mutation.js
@@ -0,0 +1,55 @@
+/* Any copyright is dedicated to the Public Domain.
+ http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+// Tests that the flexbox highlighter is hidden when the highlighted flexbox container is
+// removed from the page.
+
+const TEST_URI = `
+  <style type='text/css'>
+    #flex {
+      display: flex;
+    }
+  </style>
+  <div id="flex"></div>
+`;
+
+add_task(async function () {
+  await addTab("data:text/html;charset=utf-8," + encodeURIComponent(TEST_URI));
+  const { inspector, view } = await openRuleView();
+  const HIGHLIGHTER_TYPE = inspector.highlighters.TYPES.FLEXBOX;
+  const {
+    getNodeForActiveHighlighter,
+    waitForHighlighterTypeShown,
+    waitForHighlighterTypeHidden,
+  } = getHighlighterTestHelpers(inspector);
+
+  const onRuleViewUpdated = view.once("ruleview-refreshed");
+  await selectNode("#flex", inspector);
+  await onRuleViewUpdated;
+  const container = getRuleViewProperty(view, "#flex", "display").valueSpan;
+  const flexboxToggle = container.querySelector(
+    ".js-toggle-flexbox-highlighter"
+  );
+
+  info("Toggling ON the flexbox highlighter from the rule-view.");
+  const onHighlighterShown = waitForHighlighterTypeShown(HIGHLIGHTER_TYPE);
+  flexboxToggle.click();
+  await onHighlighterShown;
+  ok(
+    getNodeForActiveHighlighter(HIGHLIGHTER_TYPE),
+    "Flexbox highlighter is shown."
+  );
+
+  info("Remove the #flex container in the content page.");
+  const onHighlighterHidden = waitForHighlighterTypeHidden(HIGHLIGHTER_TYPE);
+  await SpecialPowers.spawn(gBrowser.selectedBrowser, [], () =>
+    content.document.querySelector("#flex").remove()
+  );
+  await onHighlighterHidden;
+  ok(
+    !getNodeForActiveHighlighter(HIGHLIGHTER_TYPE),
+    "Flexbox highlighter is hidden."
+  );
+});