diff -r 000000000000 -r 6474c204b198 dom/indexedDB/test/unit/test_overlapping_transactions.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/dom/indexedDB/test/unit/test_overlapping_transactions.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,92 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+var testGenerator = testSteps();
+
+function testSteps()
+{
+  const name = this.window ? window.location.pathname : "Splendid Test";
+  const objectStores = [ "foo", "bar" ];
+
+  let request = indexedDB.open(name, 1);
+  request.onerror = errorHandler;
+  request.onupgradeneeded = grabEventAndContinueHandler;
+  let event = yield undefined;
+
+  let db = event.target.result;
+  is(db.objectStoreNames.length, 0, "Correct objectStoreNames list");
+
+  event.target.onsuccess = grabEventAndContinueHandler;
+  for (let i in objectStores) {
+    db.createObjectStore(objectStores[i], { autoIncrement: true });
+  }
+  let event = yield undefined;
+
+  is(db.objectStoreNames.length, objectStores.length,
+     "Correct objectStoreNames list");
+
+  for (let i = 0; i < 50; i++) {
+    let stepNumber = 0;
+
+    request = db.transaction(["foo"], "readwrite")
+                .objectStore("foo")
+                .add({});
+    request.onerror = errorHandler;
+    request.onsuccess = function(event) {
+      is(stepNumber, 1, "This callback came first");
+      stepNumber++;
+      event.target.transaction.oncomplete = grabEventAndContinueHandler;
+    }
+
+    request = db.transaction(["foo"], "readwrite")
+                .objectStore("foo")
+                .add({});
+    request.onerror = errorHandler;
+    request.onsuccess = function(event) {
+      is(stepNumber, 2, "This callback came second");
+      stepNumber++;
+      event.target.transaction.oncomplete = grabEventAndContinueHandler;      
+    }
+
+    request = db.transaction(["foo", "bar"], "readwrite")
+                .objectStore("bar")
+                .add({});
+    request.onerror = errorHandler;
+    request.onsuccess = function(event) {
+      is(stepNumber, 3, "This callback came third");
+      stepNumber++;
+      event.target.transaction.oncomplete = grabEventAndContinueHandler;      
+    }
+
+    request = db.transaction(["foo", "bar"], "readwrite")
+                .objectStore("bar")
+                .add({});
+    request.onerror = errorHandler;
+    request.onsuccess = function(event) {
+      is(stepNumber, 4, "This callback came fourth");
+      stepNumber++;
+      event.target.transaction.oncomplete = grabEventAndContinueHandler;
+    }
+
+    request = db.transaction(["bar"], "readwrite")
+                .objectStore("bar")
+                .add({});
+    request.onerror = errorHandler;
+    request.onsuccess = function(event) {
+      is(stepNumber, 5, "This callback came fifth");
+      stepNumber++;
+      event.target.transaction.oncomplete = grabEventAndContinueHandler;
+    }
+
+    stepNumber++;
+    yield undefined; yield undefined; yield undefined; yield undefined; yield undefined;
+
+    is(stepNumber, 6, "All callbacks received");
+  }
+
+  finishTest();
+  yield undefined;
+}
+