1 files changed, 70 insertions, 0 deletions
diff --git a/testing/web-platform/mozilla/tests/dom/fs/fs-writable_unlocked_on_tab_close.https.window.js b/testing/web-platform/mozilla/tests/dom/fs/fs-writable_unlocked_on_tab_close.https.window.js
new file mode 100644
index 0000000000..6e8192aaef
--- /dev/null
+++ b/testing/web-platform/mozilla/tests/dom/fs/fs-writable_unlocked_on_tab_close.https.window.js
@@ -0,0 +1,70 @@
+// META: title=Origin private file system used from multiple tabs
+// META: script=support/testHelpers.js
+
+promise_test(async t => {
+  const bc = new BroadcastChannel("Coordinate writables");
+
+  function firstReady(win) {
+    return new Promise(resolve => {
+      // Blur triggers after the unload event and after window.closed is set
+      win.onblur = () => {
+        // Closing the low-level file handle may get stuck, but the unlocking
+        // request can only be sent to the parent after the handle is closed.
+        // There is no guarantee when or if the closing will be complete.
+        //
+        // Therefore, the content process shutdown does not wait for the
+        // completion but sets window.closed and calls the unload listeners
+        // while actually still holding onto some resources.
+        //
+        // Since in this test we mainly want to ensure that a file
+        // does not remain locked indefinitely, we wait for a reasonable amount
+        // of time before creating a new writable, corresponding roughly to
+        // a 500ms closing delay.
+        const timeoutMs = 400;
+        setTimeout(() => {
+          resolve(win);
+        }, timeoutMs);
+      };
+    });
+  }
+
+  const firstTabName = "support/fs-open_writable_then_close_tab.sub.html";
+  const firstTab = await firstReady(window.open(firstTabName));
+  assert_true(firstTab.closed, "Is the first tab already closed?");
+
+  function secondReady(win) {
+    return new Promise(resolve => {
+      bc.onmessage = e => {
+        if (e.data === "Second window ready!") {
+          resolve(win);
+        }
+      };
+    });
+  }
+
+  const secondTabName = "support/fs-open_writable_after_trigger.sub.html";
+  const secondTab = await secondReady(window.open(secondTabName));
+
+  let isDone = false;
+  let childStatus = "Success";
+
+  const secondSucceeded = new Promise(resolve => {
+    bc.onmessage = e => {
+      isDone = true;
+      if (e.data !== "Success") {
+        childStatus = e.data;
+      }
+
+      resolve();
+    };
+  });
+
+  bc.postMessage("Create writable in the second window");
+
+  await secondSucceeded;
+  assert_true(isDone, "Did the second tab respond?");
+
+  await fetch_tests_from_window(secondTab);
+
+  assert_equals(childStatus, "Success");
+}, `writable available for other tabs after one tab is closed`);