diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
index 4f34818..a873778 100644
--- a/test/CMakeLists.txt
+++ b/test/CMakeLists.txt
@@ -48,6 +48,7 @@ target_link_libraries(integration_sleepy folly_headers)
 # Unit tests
 
 add_executable(test_type_graph
+  main.cpp
   test_add_padding.cpp
   test_alignment_calc.cpp
   test_drgn_parser.cpp
@@ -56,6 +57,7 @@ add_executable(test_type_graph
   test_remove_top_level_pointer.cpp
   test_topo_sorter.cpp
   test_type_identifier.cpp
+  type_graph_utils.cpp
 )
 add_dependencies(test_type_graph integration_test_target)
 target_compile_definitions(test_type_graph PRIVATE
diff --git a/test/main.cpp b/test/main.cpp
new file mode 100644
index 0000000..c3686ba
--- /dev/null
+++ b/test/main.cpp
@@ -0,0 +1,19 @@
+#include <gtest/gtest.h>
+
+/*
+ * This listener ensures that test failures (ASSERTs) in helper functions
+ * propagate all the way up and stop the test from continuing.
+ */
+class ThrowListener : public testing::EmptyTestEventListener {
+  void OnTestPartResult(const testing::TestPartResult& result) override {
+    if (result.type() == testing::TestPartResult::kFatalFailure) {
+      throw testing::AssertionException(result);
+    }
+  }
+};
+
+int main(int argc, char* argv[]) {
+  ::testing::InitGoogleTest(&argc, argv);
+  ::testing::UnitTest::GetInstance()->listeners().Append(new ThrowListener);
+  return RUN_ALL_TESTS();
+}
diff --git a/test/test_add_padding.cpp b/test/test_add_padding.cpp
index c8f16b0..d02a873 100644
--- a/test/test_add_padding.cpp
+++ b/test/test_add_padding.cpp
@@ -5,30 +5,10 @@
 #include "oi/type_graph/Printer.h"
 #include "oi/type_graph/TypeGraph.h"
 #include "oi/type_graph/Types.h"
+#include "test/type_graph_utils.h"
 
 using namespace type_graph;
 
-void test(Pass pass,
-          std::vector<std::reference_wrapper<Type>> types,
-          std::string_view expected) {
-  TypeGraph typeGraph;
-  for (const auto& type : types) {
-    typeGraph.addRoot(type);
-  }
-
-  pass.run(typeGraph);
-
-  std::stringstream out;
-  Printer printer(out);
-
-  for (const auto& type : types) {
-    printer.print(type);
-  }
-
-  expected.remove_prefix(1);  // Remove initial '\n'
-  EXPECT_EQ(expected, out.str());
-}
-
 TEST(AddPaddingTest, BetweenMembers) {
   auto myclass = std::make_unique<Class>(Class::Kind::Class, "MyClass", 16);
   auto myint8 = std::make_unique<Primitive>(Primitive::Kind::Int8);
diff --git a/test/test_name_gen.cpp b/test/test_name_gen.cpp
index ae8044e..44ba065 100644
--- a/test/test_name_gen.cpp
+++ b/test/test_name_gen.cpp
@@ -1,17 +1,11 @@
 #include <gtest/gtest.h>
 
-#include "oi/ContainerInfo.h"
 #include "oi/type_graph/NameGen.h"
 #include "oi/type_graph/Types.h"
+#include "test/type_graph_utils.h"
 
 using namespace type_graph;
 
-Container getVector() {
-  ContainerInfo info{"std::vector", SEQ_TYPE, "vector"};
-
-  return Container{info, 24};
-}
-
 TEST(NameGenTest, ClassParams) {
   auto myparam1 = std::make_unique<Class>(Class::Kind::Struct, "MyParam", 13);
   auto myparam2 = std::make_unique<Class>(Class::Kind::Struct, "MyParam", 13);
diff --git a/test/type_graph_utils.cpp b/test/type_graph_utils.cpp
new file mode 100644
index 0000000..49ed491
--- /dev/null
+++ b/test/type_graph_utils.cpp
@@ -0,0 +1,68 @@
+#include "test/type_graph_utils.h"
+
+#include <gtest/gtest.h>
+
+#include "oi/ContainerInfo.h"
+#include "oi/type_graph/PassManager.h"
+#include "oi/type_graph/Printer.h"
+#include "oi/type_graph/TypeGraph.h"
+
+using type_graph::Container;
+using type_graph::Pass;
+using type_graph::Type;
+using type_graph::TypeGraph;
+
+template <typename T>
+using ref = std::reference_wrapper<T>;
+
+namespace {
+void check(const std::vector<ref<Type>>& types,
+           std::string_view expected,
+           std::string_view comment) {
+  std::stringstream out;
+  type_graph::Printer printer(out);
+
+  for (const auto& type : types) {
+    printer.print(type);
+  }
+
+  expected.remove_prefix(1);  // Remove initial '\n'
+  ASSERT_EQ(expected, out.str())
+      << "Test failure " << comment << " running pass";
+}
+}  // namespace
+
+void test(type_graph::Pass pass,
+          std::vector<ref<Type>> rootTypes,
+          std::string_view expectedBefore,
+          std::string_view expectedAfter) {
+  check(rootTypes, expectedBefore, "before");
+
+  TypeGraph typeGraph;
+  for (const auto& type : rootTypes) {
+    typeGraph.addRoot(type);
+  }
+
+  pass.run(typeGraph);
+
+  check(rootTypes, expectedAfter, "after");
+}
+
+void test(type_graph::Pass pass,
+          std::vector<ref<Type>> rootTypes,
+          std::string_view expectedAfter) {
+  TypeGraph typeGraph;
+  for (const auto& type : rootTypes) {
+    typeGraph.addRoot(type);
+  }
+
+  pass.run(typeGraph);
+
+  check(rootTypes, expectedAfter, "after");
+}
+
+Container getVector() {
+  static ContainerInfo info{"std::vector", SEQ_TYPE, "vector"};
+  info.stubTemplateParams = {1};
+  return Container{info, 24};
+}
diff --git a/test/type_graph_utils.h b/test/type_graph_utils.h
new file mode 100644
index 0000000..c339557
--- /dev/null
+++ b/test/type_graph_utils.h
@@ -0,0 +1,22 @@
+#pragma once
+
+#include <functional>
+#include <string_view>
+#include <vector>
+
+namespace type_graph {
+class Container;
+class Pass;
+class Type;
+}  // namespace type_graph
+
+void test(type_graph::Pass pass,
+          std::vector<std::reference_wrapper<type_graph::Type>> rootTypes,
+          std::string_view expectedBefore,
+          std::string_view expectedAfter);
+
+void test(type_graph::Pass pass,
+          std::vector<std::reference_wrapper<type_graph::Type>> rootTypes,
+          std::string_view expectedAfter);
+
+type_graph::Container getVector();