test: Use test-listener rather than TestBase to assure quiescence after each method.

test/test_common/test_base.cc

@@ -6,13 +6,12 @@
 
 namespace Envoy {
 
-void TestBase::checkSingletonQuiescensce() {
+void TestListener::OnTestEnd(const ::testing::TestInfo& test_info) {
   // Check that all singletons have been destroyed.
   std::string active_singletons = Envoy::Test::Globals::describeActiveSingletons();
   RELEASE_ASSERT(active_singletons.empty(),
-                 absl::StrCat("FAIL: Active singletons exist:\n", active_singletons));
+                 absl::StrCat("FAIL [", test_info.test_suite_name(), ".", test_info.name(),
+                              "]: Active singletons exist:\n", active_singletons));
 }
 
-TestBase::~TestBase() { checkSingletonQuiescensce(); }
-
 } // namespace Envoy

test/test_common/test_base.h

@@ -4,7 +4,7 @@
 
 namespace Envoy {
 
-// Provides a common test-base class for all tests in Envoy to use. This offers
+// Provides a test listener to be called after each test method. This offers
 // a place to put hooks we'd like to run on every test. There's currently a
 // check that all test-scoped singletons have been destroyed. A test-scoped
 // singleton might remain at the end of a test if it's transitively referenced
@@ -17,18 +17,16 @@ namespace Envoy {
 //     than there were at the start of it. This is likely to fail in a few
 //     places when introduced, but we could add known test overrides for this.
 //
-// Note: nothing compute-intensive should be put in this test-class, as it will
+// Note: nothing compute-intensive should be put in this class, as it will
 // be a tax paid by every test method in the codebase.
-class TestBase : public ::testing::Test {
-public:
-  static void checkSingletonQuiescensce();
-  ~TestBase() override;
+class TestListener : public ::testing::EmptyTestEventListener {
+  void OnTestEnd(const ::testing::TestInfo& test_info) override;
 };
 
-// Templatized version of TestBase. See above notes.
-template <class T> class TestBaseWithParam : public ::testing::TestWithParam<T> {
-public:
-  ~TestBaseWithParam() { TestBase::checkSingletonQuiescensce(); }
-};
+// TODO(jmarantz): Before Alyssa found this TestListener hook for me, we had
+// merged a PR that added the same functionality via common TestBase classes.
+// These should be removed.
+using TestBase = ::testing::Test;
+template <class T> using TestBaseWithParam = ::testing::TestWithParam<T>;
 
 } // namespace Envoy

test/test_runner.h

@@ -18,6 +18,13 @@ class TestRunner {
     ::testing::InitGoogleMock(&argc, argv);
     Event::Libevent::Global::initialize();
 
+    // Add a test-listener so we can call a hook where we can do a quiescence
+    // check after each method. See
+    // https://github.com/google/googletest/blob/master/googletest/docs/advanced.md
+    // for details.
+    ::testing::TestEventListeners& listeners = ::testing::UnitTest::GetInstance()->listeners();
+    listeners.Append(new TestListener);
+
     // Use the recommended, but not default, "threadsafe" style for the Death Tests.
     // See: https://github.com/google/googletest/commit/84ec2e0365d791e4ebc7ec249f09078fb5ab6caa
     ::testing::FLAGS_gtest_death_test_style = "threadsafe";
@@ -45,12 +52,7 @@ class TestRunner {
       file_logger = std::make_unique<Logger::FileSinkDelegate>(
           TestEnvironment::getOptions().logPath(), access_log_manager, Logger::Registry::getSink());
     }
-    int exit_status = RUN_ALL_TESTS();
-
-    // Check that all singletons have been destroyed.
-    TestBase::checkSingletonQuiescensce();
-
-    return exit_status;
+    return RUN_ALL_TESTS();
   }
 };
 } // namespace Envoy