1 files changed, 53 insertions, 0 deletions
diff --git a/devtools/client/responsive/test/browser/browser_tab_close.js b/devtools/client/responsive/test/browser/browser_tab_close.js
new file mode 100644
index 0000000000..6abe3536f9
--- /dev/null
+++ b/devtools/client/responsive/test/browser/browser_tab_close.js
@@ -0,0 +1,53 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+// Verify RDM closes synchronously when tabs are closed.
+
+const TEST_URL = "http://example.com/";
+
+addRDMTask(
+  null,
+  async function () {
+    const tab = await addTab(TEST_URL);
+
+    const { ui } = await openRDM(tab);
+    await waitForDeviceAndViewportState(ui);
+    const clientClosed = waitForClientClose(ui);
+
+    closeRDM(tab, {
+      reason: "TabClose",
+    });
+
+    // This flag is set at the end of `ResponsiveUI.destroy`.  If it is true
+    // without waiting for `closeRDM` above, then we must have closed
+    // synchronously.
+    is(ui.destroyed, true, "RDM closed synchronously");
+
+    await clientClosed;
+    await removeTab(tab);
+  },
+  { onlyPrefAndTask: true }
+);
+
+addRDMTask(
+  null,
+  async function () {
+    const tab = await addTab(TEST_URL);
+
+    const { ui } = await openRDM(tab);
+    await waitForDeviceAndViewportState(ui);
+    const clientClosed = waitForClientClose(ui);
+
+    await removeTab(tab);
+
+    // This flag is set at the end of `ResponsiveUI.destroy`.  If it is true without
+    // waiting for `closeRDM` itself and only removing the tab, then we must have closed
+    // synchronously in response to tab closing.
+    is(ui.destroyed, true, "RDM closed synchronously");
+
+    await clientClosed;
+  },
+  { onlyPrefAndTask: true }
+);