[lldb] Add a SubsystemRAII that takes care of calling Initialize and Terminate in the unit tests

Summary:
Many of our tests need to initialize certain subsystems/plugins of LLDB such as
`FileSystem` or `HostInfo` by calling their static `Initialize` functions before the
test starts and then calling `::Terminate` after the test is done (in reverse order).
This adds a lot of error-prone boilerplate code to our testing code.

This patch adds a RAII called SubsystemRAII that ensures that we always call
::Initialize and then call ::Terminate after the test is done (and that the Terminate
calls are always in the reverse order of the ::Initialize calls). It also gets rid of
all of the boilerplate that we had for these calls.

Per-fixture initialization is still not very nice with this approach as it would
require some kind of static unique_ptr that gets manually assigned/reseted
from the gtest SetUpTestCase/TearDownTestCase functions. Because of that
I changed all per-fixture setup to now do per-test setup which can be done
by just having the SubsystemRAII as a member of the test fixture. This change doesn't
influence our normal test runtime as LIT anyway runs each test case separately
(and the Initialize/Terminate calls are anyway not very expensive). It will however
make running all tests in a single executable slightly slower.

Reviewers: labath, JDevlieghere, martong, espindola, shafik

Reviewed By: labath

Subscribers: mgorny, rnkovacs, emaste, MaskRay, abidh, lldb-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D71630

1 files changed, 5 insertions, 13 deletions

diff --git a/lldb/unittests/Symbol/TestLineEntry.cpp b/lldb/unittests/Symbol/TestLineEntry.cpp
index b6325fa115b..cb2adba3ece 100644
--- a/lldb/unittests/Symbol/TestLineEntry.cpp
+++ b/lldb/unittests/Symbol/TestLineEntry.cpp
@@ -14,6 +14,7 @@
 #include "Plugins/ObjectFile/Mach-O/ObjectFileMachO.h"
 #include "Plugins/SymbolFile/DWARF/DWARFASTParserClang.h"
 #include "Plugins/SymbolFile/DWARF/SymbolFileDWARF.h"
+#include "TestingSupport/SubsystemRAII.h"
 #include "TestingSupport/TestUtilities.h"
 #include "lldb/Symbol/ClangASTContext.h"
 
@@ -31,17 +32,13 @@ using namespace lldb_private;
 using namespace lldb;
 
 class LineEntryTest : public testing::Test {
+  SubsystemRAII<FileSystem, HostInfo, ObjectFileMachO, SymbolFileDWARF,
+                ClangASTContext>
+      subsystem;
+
 public:
   void SetUp() override;
 
-  void TearDown() override {
-    ClangASTContext::Terminate();
-    SymbolFileDWARF::Terminate();
-    ObjectFileMachO::Terminate();
-    HostInfo::Terminate();
-    FileSystem::Terminate();
-  }
-
 protected:
   llvm::Expected<LineEntry> GetLineEntryForLine(uint32_t line);
   llvm::Optional<TestFile> m_file;
@@ -49,11 +46,6 @@ protected:
 };
 
 void LineEntryTest::SetUp() {
-  FileSystem::Initialize();
-  HostInfo::Initialize();
-  ObjectFileMachO::Initialize();
-  SymbolFileDWARF::Initialize();
-  ClangASTContext::Initialize();
   auto ExpectedFile = TestFile::fromYamlFile("inlined-functions.yaml");
   ASSERT_THAT_EXPECTED(ExpectedFile, llvm::Succeeded());
   m_file.emplace(std::move(*ExpectedFile));