MXS-1507: Test resultset checksum functionality

The test verifies that different results returned by the replayed
transaction cause the replaying to be aborted.

maxscale-system-test/CMakeLists.txt

@@ -617,6 +617,10 @@ add_test_executable(mxs1506_no_master.cpp mxs1506_no_master mxs1506_delayed_retr
 # https://jira.mariadb.org/browse/MXS-1507
 add_test_executable(mxs1507_trx_replay.cpp mxs1507_trx_replay mxs1507_trx_replay LABELS readwritesplit REPL_BACKEND)
 
+# MXS-1507: Inconsistent transactions
+# https://jira.mariadb.org/browse/MXS-1507
+add_test_executable(mxs1507_inconsistent_trx.cpp mxs1507_inconsistent_trx mxs1507_trx_replay LABELS readwritesplit REPL_BACKEND)
+
 # MXS-1509: Show correct server state for multisource replication
 # https://jira.mariadb.org/browse/MXS-1509
 add_test_executable(mxs1509.cpp mxs1509 mxs1509 LABELS mysqlmon REPL_BACKEND)

maxscale-system-test/mxs1507_inconsistent_trx.cpp

@@ -0,0 +1,63 @@
+/**
+ * MXS-1507: Test inconsistent result detection
+ *
+ * https://jira.mariadb.org/browse/MXS-1507
+ */
+#include "testconnections.h"
+#include <functional>
+#include <iostream>
+#include <vector>
+
+using namespace std;
+
+int main(int argc, char** argv)
+{
+    TestConnections test(argc, argv);
+
+    auto query = [&](string q)
+    {
+        return execute_query_silent(test.maxscales->conn_rwsplit[0], q.c_str()) == 0;
+    };
+
+    auto ok = [&](string q)
+    {
+        test.assert(query(q), "Query '%s' should work: %s", q.c_str(), mysql_error(test.maxscales->conn_rwsplit[0]));
+    };
+
+    auto err = [&](string q)
+    {
+        test.assert(!query(q), "Query should not work: %s", q.c_str());
+    };
+
+    // Create a table and insert one value
+    test.maxscales->connect();
+    ok("CREATE OR REPLACE TABLE test.t1 (id INT)");
+    ok("INSERT INTO test.t1 VALUES (1)");
+
+    // Make sure it's replicated to all slaves before starting the transaction
+    test.repl->connect();
+    test.repl->sync_slaves();
+
+    // Read the inserted value inside a read-only transaction
+    ok("START TRANSACTION READ ONLY");
+    ok("SELECT * FROM test.t1");
+
+    // Modify the related data mid-transaction
+    execute_query(test.repl->nodes[0], "INSERT INTO test.t1 VALUES (2)");
+    test.repl->sync_slaves();
+    test.repl->disconnect();
+
+    // Block the node where the transaction is active
+    test.repl->block_node(1);
+    sleep(5);
+
+    // The checksums for the results should conflict causing the replay to fail
+    err("COMMIT");
+    test.maxscales->disconnect();
+
+    test.maxscales->connect();
+    ok("DROP TABLE test.t1");
+    test.maxscales->disconnect();
+
+    return test.global_result;
+}