integration: enable DCExecutionProfileTest_DCAware test

The test DCExecutionProfileTest.DCAware was disabled because it expected
deterministic behaviour of the token-unaware round robin load balancing.
As the Rust Driver round-robins nodes with a random shift, the test
would fail. I reworked it to check that the node in the other DC is not
used, instead of expecting a specific node in the local DC to be used.

The test is now enabled in the Makefile.

Author: wprzytula

Makefile

@@ -46,7 +46,6 @@ SCYLLA_TEST_FILTER := $(subst ${SPACE},${EMPTY},ClusterTests.*\
 :ExecutionProfileTest.Integration_Cassandra_RoundRobin\
 :ExecutionProfileTest.Integration_Cassandra_TokenAwareRouting\
 :ExecutionProfileTest.Integration_Cassandra_SpeculativeExecutionPolicy\
-:DCExecutionProfileTest.Integration_Cassandra_DCAware\
 :ControlConnectionTests.Integration_Cassandra_TopologyChange\
 :ControlConnectionTests.Integration_Cassandra_FullOutage\
 :ControlConnectionTests.Integration_Cassandra_TerminatedUsingMultipleIoThreadsWithError\

tests/src/integration/tests/test_exec_profile.cpp

@@ -715,35 +715,31 @@ CASSANDRA_INTEGRATION_TEST_F(ExecutionProfileTest, SpeculativeExecutionPolicy) {
 CASSANDRA_INTEGRATION_TEST_F(DCExecutionProfileTest, DCAware) {
   CHECK_FAILURE;
 
+  // Determine the disallowed IP address for the statement DC-aware execution
+  int const unexpected_node = 3; // The node in DC2.
+  std::stringstream unexpected_ip_address;
+  unexpected_ip_address << ccm_->get_ip_prefix() << unexpected_node;
+
   // Execute statements over all the nodes in the cluster twice
   for (size_t i = 0; i < total_nodes_ * 2; ++i) {
     // Execute the same query with the cluster default profile
     insert_.set_execution_profile(""); // Reset the insert statement
     Result result = session_.execute(insert_);
     ASSERT_EQ(CASS_OK, result.error_code());
 
-    // Determine the expected IP address for the statement execution
-    int expected_node = ((i * 2) % number_dc1_nodes_) + 1;
-    std::stringstream expected_ip_address;
-    expected_ip_address << ccm_->get_ip_prefix() << expected_node;
-
     // Execute a batched query with assigned profile
     Batch batch;
     batch.add(insert_);
     batch.set_execution_profile("dc_aware");
     result = session_.execute(batch);
     ASSERT_EQ(CASS_OK, result.error_code());
-    ASSERT_STREQ(expected_ip_address.str().c_str(), result.host().c_str());
-
-    // Increment the expected round robin IP address
-    expected_ip_address.str("");
-    expected_ip_address << ccm_->get_ip_prefix() << expected_node + 1;
+    ASSERT_STRNE(unexpected_ip_address.str().c_str(), result.host().c_str());
 
     // Execute a simple query with assigned profile
     insert_.set_execution_profile("dc_aware");
     result = session_.execute(insert_);
     ASSERT_EQ(CASS_OK, result.error_code());
-    ASSERT_STREQ(expected_ip_address.str().c_str(), result.host().c_str());
+    ASSERT_STRNE(unexpected_ip_address.str().c_str(), result.host().c_str());
   }
 }