diff --git a/mozilla/editor/txmgr/tests/TestTXMgr.cpp b/mozilla/editor/txmgr/tests/TestTXMgr.cpp
index faa2b67f7a9..28aca7148a7 100644
--- a/mozilla/editor/txmgr/tests/TestTXMgr.cpp
+++ b/mozilla/editor/txmgr/tests/TestTXMgr.cpp
@@ -1,8 +1,150 @@
-#include "nsITransactionManager.h"
+#include "nsTransactionManager.h"
+
+class TestTransaction : public nsITransaction
+{
+public:
+
+  TestTransaction()  {}
+  ~TestTransaction()
+  {
+    printf("~TestTransaction: 0x%.8x\n", this);
+  }
+
+  NS_DECL_ISUPPORTS
+
+  virtual nsresult Do()
+  {
+    printf("0x%.8x: Do()\n", this);
+    return NS_OK;
+  }
+
+  virtual nsresult Undo()
+  {
+    printf("0x%.8x: Undo()\n", this);
+    return NS_OK;
+  }
+
+  virtual nsresult Redo()
+  {
+    printf("0x%.8x: Redo()\n", this);
+    return NS_OK;
+  }
+
+  virtual nsresult Write(nsIOutputStream *aOutputStream)
+  {
+    return NS_OK;
+  }
+
+  virtual nsresult GetUndoString(nsString **aString)
+  {
+    *aString = 0;
+    return NS_OK;
+  }
+
+  virtual nsresult GetRedoString(nsString **aString)
+  {
+    *aString = 0;
+    return NS_OK;
+  }
+
+};
+
+NS_IMPL_ADDREF(TestTransaction)
+NS_IMPL_RELEASE(TestTransaction)
+
+static NS_DEFINE_IID(kISupportsIID, NS_ISUPPORTS_IID);
+static NS_DEFINE_IID(kITransactionIID, NS_ITRANSACTION_IID);
+
+nsresult
+TestTransaction::QueryInterface(REFNSIID aIID, void** aInstancePtr)
+{
+  if (NULL == aInstancePtr) {
+    return NS_ERROR_NULL_POINTER;
+  }
+  if (aIID.Equals(kISupportsIID)) {
+    *aInstancePtr = (void*)(nsISupports*)this;
+    NS_ADDREF_THIS();
+    return NS_OK;
+  }
+  if (aIID.Equals(kITransactionIID)) {
+    *aInstancePtr = (void*)(nsITransaction*)this;
+    NS_ADDREF_THIS();
+    return NS_OK;
+  }
+  *aInstancePtr = 0;
+  return NS_NOINTERFACE;
+}
+
+class TestDoErrorTransaction : public TestTransaction
+{
+public:
+
+  virtual nsresult Do()
+  {
+    TestTransaction::Do();
+    return NS_ERROR_FAILURE;
+  }
+};
+
+class TestUndoErrorTransaction : public TestTransaction
+{
+public:
+
+  virtual nsresult Undo()
+  {
+    TestTransaction::Undo();
+    return NS_ERROR_FAILURE;
+  }
+};
+
+class TestRedoErrorTransaction : public TestTransaction
+{
+public:
+
+  virtual nsresult Redo()
+  {
+    TestTransaction::Redo();
+    return NS_ERROR_FAILURE;
+  }
+};
 
 int
 main (int argc, char *argv[])
 {
+  nsTransactionManager     *mgr = new nsTransactionManager();
+  TestTransaction          *tt  = new TestTransaction();
+  TestDoErrorTransaction   *det = new TestDoErrorTransaction();
+  TestUndoErrorTransaction *uet = new TestUndoErrorTransaction();
+  TestRedoErrorTransaction *ret = new TestRedoErrorTransaction();
+
+  mgr->AddRef();
+
+  printf("-- TestTransaction: 0x%.8x\n", (nsITransaction *)tt);
+  mgr->Do(tt);
+  mgr->Undo();
+  mgr->Redo();
+  mgr->Undo();
+
+  printf("-- TestDoErrorTransaction: 0x%.8x\n", (nsITransaction *)det);
+  mgr->Do(det);
+  mgr->Undo();
+  mgr->Redo();
+  mgr->Undo();
+
+  printf("-- TestUndoErrorTransaction: 0x%.8x\n", (nsITransaction *)uet);
+  mgr->Do(uet);
+  mgr->Undo();
+  mgr->Redo();
+  mgr->Undo();
+
+  printf("-- TestRedoErrorTransaction: 0x%.8x\n", (nsITransaction *)ret);
+  mgr->Do(ret);
+  mgr->Undo();
+  mgr->Redo();
+  mgr->Undo();
+
+  mgr->Release();
+
   return 0;
 }