print stats in fuzzer

Author: karthikeyann

velox/exec/fuzzer/JoinFuzzer.cpp

@@ -430,8 +430,9 @@ RowVectorPtr JoinFuzzer::execute(
 
   TestScopedSpillInjection scopedSpillInjection(spillPct);
   RowVectorPtr result;
+  TaskStats stats;
   try {
-    result = builder.maxDrivers(2).copyResults(pool_.get());
+    std::tie(result, stats) = builder.maxDrivers(2).copyResultsWithStats(pool_.get());
   } catch (VeloxRuntimeError& e) {
     if (FLAGS_enable_oom_injection &&
         e.errorCode() == facebook::velox::error_code::kMemCapExceeded &&
@@ -451,6 +452,8 @@ RowVectorPtr JoinFuzzer::execute(
   // avoid the potential interference of the background activities across query
   // executions.
   test::waitForAllTasksToBeDeleted();
+  std::cout << exec::printPlanWithStats(*plan.plan, stats, true)
+          << std::endl;
   return result;
 }
 

velox/exec/tests/utils/AssertQueryBuilder.cpp

@@ -226,6 +226,14 @@ RowVectorPtr AssertQueryBuilder::copyResults(memory::MemoryPool* pool) {
   return copyResults(pool, unused);
 }
 
+std::pair<RowVectorPtr, TaskStats> AssertQueryBuilder::copyResultsWithStats(memory::MemoryPool* pool) {
+  std::shared_ptr<Task> unused;
+  auto result = copyResults(pool, unused);
+  auto stats = unused->taskStats();
+  return std::make_pair(result, stats);
+}
+
+
 RowVectorPtr AssertQueryBuilder::copyResults(
     memory::MemoryPool* pool,
     std::shared_ptr<Task>& task) {

velox/exec/tests/utils/AssertQueryBuilder.h

@@ -178,6 +178,8 @@ class AssertQueryBuilder {
   /// query returns empty result.
   RowVectorPtr copyResults(memory::MemoryPool* pool);
 
+  std::pair<RowVectorPtr, TaskStats> copyResultsWithStats(memory::MemoryPool* pool);
+
   /// Similar to above method and also returns the task.
   RowVectorPtr copyResults(
       memory::MemoryPool* pool,