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+/**
+ * This test attempts to reproduce the bug described in SERVER-48002. This is a best-effort test
+ * that will not detect this bug on every run, even if a bug exists.
+ *
+ * Snapshot isolation cannot be guaranteed for operations that ignore prepare conflicts.
+ * This means that two reads of the same record in the same snapshot can return different results.
+ * In practice, the DataCorruptionDetected assertion added by SERVER-40620 will trigger if an index
+ * points to a non-existent record.
+ *
+ * Queries that ignore prepare conflicts and use an index to satisfy a read can read a key from an
+ * index and fetch a record that appears to go missing within the same snapshot. This may happen
+ * when the collection read races with a prepared transaction that commits and deletes the record.
+ *
+ *
+ * @tags: [
+ * uses_prepare_transaction,
+ * uses_transactions,
+ * ]
+ */
+(function() {
+"use strict";
+
+const replTest = new ReplSetTest({nodes: 2});
+replTest.startSet();
+replTest.initiate();
+
+const primary = replTest.getPrimary();
+const dbName = "query_with_txn_prepared";
+const collName = "coll";
+
+assert.commandWorked(primary.getDB(dbName)[collName].createIndexes([{x: 1}]));
+
+const transactionShell = startParallelShell(function() {
+ load("jstests/core/txns/libs/prepare_helpers.js"); // For PrepareHelpers.
+
+ while (db.getSiblingDB("query_with_txn_prepared")["stopQueries"].find().count() == 0) {
+ for (let i = 0; i < 100; ++i) {
+ const session = db.getMongo().startSession();
+ const sessionColl = session.getDatabase("query_with_txn_prepared")["coll"];
+
+ session.startTransaction({readConcern: {level: "majority"}});
+ if (Math.random() < 0.5) {
+ assert.commandWorked(sessionColl.update({x: 1}, {x: 1}, {upsert: true}));
+ } else {
+ assert.commandWorked(sessionColl.remove({x: 1}));
+ }
+
+ const prepareTimestamp = PrepareHelpers.prepareTransaction(session);
+ assert.commandWorked(PrepareHelpers.commitTransaction(session, prepareTimestamp));
+ }
+ }
+}, primary.port);
+
+for (let i = 0; i < 2000; ++i) {
+ const result = primary.getDB(dbName)[collName].find({x: 1}).toArray();
+ assert([0, 1].includes(result.length), result);
+}
+
+assert.commandWorked(primary.getDB(dbName)["stopQueries"].insert({stop: 1}));
+transactionShell();
+
+replTest.stopSet();
+}());