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diff --git a/src/third_party/wiredtiger/test/suite/test_txn27.py b/src/third_party/wiredtiger/test/suite/test_txn27.py
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+++ b/src/third_party/wiredtiger/test/suite/test_txn27.py
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+#!/usr/bin/env python
+#
+# Public Domain 2014-present MongoDB, Inc.
+# Public Domain 2008-2014 WiredTiger, Inc.
+#
+# This is free and unencumbered software released into the public domain.
+#
+# Anyone is free to copy, modify, publish, use, compile, sell, or
+# distribute this software, either in source code form or as a compiled
+# binary, for any purpose, commercial or non-commercial, and by any
+# means.
+#
+# In jurisdictions that recognize copyright laws, the author or authors
+# of this software dedicate any and all copyright interest in the
+# software to the public domain. We make this dedication for the benefit
+# of the public at large and to the detriment of our heirs and
+# successors. We intend this dedication to be an overt act of
+# relinquishment in perpetuity of all present and future rights to this
+# software under copyright law.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+# IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR
+# OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+# ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+# OTHER DEALINGS IN THE SOFTWARE.
+
+import wiredtiger, wttest, time
+from wtdataset import SimpleDataSet
+
+# test_txn27.py
+#   Test that the API returning a rollback error sets the reason for the rollback.
+class test_txn27(wttest.WiredTigerTestCase):
+    conn_config = 'cache_size=1MB'
+
+    def test_rollback_reason(self):
+        uri = "table:txn27"
+        # Create a very basic table.
+        ds = SimpleDataSet(self, uri, 10, key_format='S', value_format='S')
+        ds.populate()
+
+        # Update key 5 in the first session.
+        session1 = self.session
+        cursor1 = session1.open_cursor(uri)
+        session1.begin_transaction()
+        cursor1[ds.key(5)] = "aaa"
+
+        # Update the same key in the second session, expect a conflict error to be produced.
+        session2 = self.conn.open_session()
+        cursor2 = session2.open_cursor(uri)
+        session2.begin_transaction()
+        cursor2.set_key(ds.key(5))
+        cursor2.set_value("bbb")
+        msg1 = '/conflict between concurrent operations/'
+        self.assertRaisesException(wiredtiger.WiredTigerError, lambda: cursor2.update(), msg1)
+        self.assertEquals('/' + session2.get_rollback_reason() + '/', msg1)
+
+        # Rollback the transactions, check that session2's rollback error was cleared.
+        session2.rollback_transaction()
+        self.assertEquals(session2.get_rollback_reason(), None)
+        session1.rollback_transaction()
+
+        # Start a new transaction and insert a value far too large for cache.
+        session1.begin_transaction()
+        cursor1.set_key(ds.key(1))
+        cursor1.set_value("a"*1024*5000)
+        self.assertEqual(0, cursor1.update())
+
+        # Let WiredTiger's accounting catch up.
+        time.sleep(2)
+
+        # Attempt to insert another value with the same transaction. This will result in the
+        # application thread being pulled into eviction and getting rolled back.
+        cursor1.set_key(ds.key(2))
+        cursor1.set_value("b"*1024)
+
+        # This is the message that we expect to be raised when a thread is rolled back due to
+        # cache pressure.
+        msg2 = 'oldest pinned transaction ID rolled back for eviction'
+        # Expect stdout to give us the true reason for the rollback.
+        with self.expectedStdoutPattern(msg2):
+            # This reason is the default reason for WT_ROLLBACK errors so we need to catch it.
+            self.assertRaisesException(wiredtiger.WiredTigerError, lambda: cursor1.update(), msg1)
+        # Expect the rollback reason to give us the true reason for the rollback.
+        self.assertEquals(session1.get_rollback_reason(), msg2)
+
+if __name__ == '__main__':
+    wttest.run()