1 files changed, 55 insertions, 0 deletions
diff --git a/devtools/client/inspector/rules/test/browser_rules_grid-highlighter-on-reload.js b/devtools/client/inspector/rules/test/browser_rules_grid-highlighter-on-reload.js
new file mode 100644
index 0000000000..7850b069ae
--- /dev/null
+++ b/devtools/client/inspector/rules/test/browser_rules_grid-highlighter-on-reload.js
@@ -0,0 +1,55 @@
+/* Any copyright is dedicated to the Public Domain.
+ http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+// Test that a grid highlighter showing grid gaps can be displayed after reloading the
+// page (Bug 1342051).
+
+const TEST_URI = `
+  <style type='text/css'>
+    #grid {
+      display: grid;
+      grid-gap: 10px;
+    }
+  </style>
+  <div id="grid">
+    <div id="cell1">cell1</div>
+    <div id="cell2">cell2</div>
+  </div>
+`;
+
+add_task(async function () {
+  await addTab("data:text/html;charset=utf-8," + encodeURIComponent(TEST_URI));
+
+  info("Check that the grid highlighter can be displayed");
+  await checkGridHighlighter();
+
+  info("Close the toolbox before reloading the tab");
+  await gDevTools.closeToolboxForTab(gBrowser.selectedTab);
+
+  await reloadBrowser();
+
+  info(
+    "Check that the grid highlighter can be displayed after reloading the page"
+  );
+  await checkGridHighlighter();
+});
+
+async function checkGridHighlighter() {
+  const { inspector, view } = await openRuleView();
+  const { highlighters } = inspector;
+  const HIGHLIGHTER_TYPE = inspector.highlighters.TYPES.GRID;
+  const { waitForHighlighterTypeShown } = getHighlighterTestHelpers(inspector);
+
+  await selectNode("#grid", inspector);
+  const container = getRuleViewProperty(view, "#grid", "display").valueSpan;
+  const gridToggle = container.querySelector(".js-toggle-grid-highlighter");
+
+  info("Toggling ON the CSS grid highlighter from the rule-view.");
+  const onHighlighterShown = waitForHighlighterTypeShown(HIGHLIGHTER_TYPE);
+  gridToggle.click();
+  await onHighlighterShown;
+
+  is(highlighters.gridHighlighters.size, 1, "CSS grid highlighter is shown.");
+}