1 files changed, 32 insertions, 0 deletions
diff --git a/devtools/client/inspector/test/browser_inspector_pane-toggle-layout-invariant.js b/devtools/client/inspector/test/browser_inspector_pane-toggle-layout-invariant.js
new file mode 100644
index 0000000000..1abc7db975
--- /dev/null
+++ b/devtools/client/inspector/test/browser_inspector_pane-toggle-layout-invariant.js
@@ -0,0 +1,32 @@
+/* Any copyright is dedicated to the Public Domain.
+ http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+// Test that documents with suppressed whitespace nodes are unaffected by the
+// activation of the inspector panel.
+
+const TEST_URL = URL_ROOT + "doc_inspector_pane-toggle-layout-invariant.html";
+
+async function getInvariantRect() {
+  return SpecialPowers.spawn(gBrowser.selectedBrowser, [], async function () {
+    const invariant = content.document.getElementById("invariant");
+    return invariant.getBoundingClientRect();
+  });
+}
+
+add_task(async function () {
+  await addTab(TEST_URL);
+
+  // Get the initial position of the "invariant" element. We'll later check it
+  // again and we'll expect to get the same value.
+  const beforeRect = await getInvariantRect();
+
+  // Open the inspector.
+  await openInspector();
+
+  const afterRect = await getInvariantRect();
+
+  is(afterRect.x, beforeRect.x, "invariant x should be same as initial value.");
+  is(afterRect.y, beforeRect.y, "invariant y should be same as initial value.");
+});