Disable stdin/stdout for environment_check inferior process

To work around an address sanitizer issue on macOS where
environment_check prints a spurious stderr msg when executing,

environment_check(41292,0x113e7a600) malloc: nano zone abandoned due to inability to preallocate reserved vm space.

And TestClient::Continue() which intends to continue to exit
instead sees the stderr output streamed, and doesn't handle that
unexpected output.  Easiest to disable stdin/stdout for this
one test case to avoid this corner case issue with this TestClient.cpp
way of expecting a stop reply packet after continuing.

Differential Revision: https://reviews.llvm.org/D158237

Author: jasonmolenda

lldb/unittests/tools/lldb-server/tests/LLGSTest.cpp

@@ -41,9 +41,10 @@ TEST_F(TestBase, DS_TEST(DebugserverEnv)) {
   // Test that --env takes precedence over inherited environment variables.
   putenv(const_cast<char *>("LLDB_TEST_MAGIC_VARIABLE=foobar"));
 
-  auto ClientOr = TestClient::launchCustom(getLogFileName(),
-      { "--env", "LLDB_TEST_MAGIC_VARIABLE=LLDB_TEST_MAGIC_VALUE" },
-                                     {getInferiorPath("environment_check")});
+  auto ClientOr = TestClient::launchCustom(
+      getLogFileName(), /* disable_stdio */ true,
+      {"--env", "LLDB_TEST_MAGIC_VARIABLE=LLDB_TEST_MAGIC_VALUE"},
+      {getInferiorPath("environment_check")});
   ASSERT_THAT_EXPECTED(ClientOr, Succeeded());
   auto &Client = **ClientOr;
 

lldb/unittests/tools/lldb-server/tests/TestClient.cpp

@@ -59,10 +59,13 @@ Expected<std::unique_ptr<TestClient>> TestClient::launch(StringRef Log) {
 }
 
 Expected<std::unique_ptr<TestClient>> TestClient::launch(StringRef Log, ArrayRef<StringRef> InferiorArgs) {
-  return launchCustom(Log, {}, InferiorArgs);
+  return launchCustom(Log, false, {}, InferiorArgs);
 }
 
-Expected<std::unique_ptr<TestClient>> TestClient::launchCustom(StringRef Log, ArrayRef<StringRef> ServerArgs, ArrayRef<StringRef> InferiorArgs) {
+Expected<std::unique_ptr<TestClient>>
+TestClient::launchCustom(StringRef Log, bool disable_stdio,
+                         ArrayRef<StringRef> ServerArgs,
+                         ArrayRef<StringRef> InferiorArgs) {
   const ArchSpec &arch_spec = HostInfo::GetArchitecture();
   Args args;
   args.AppendArgument(LLDB_SERVER);
@@ -111,6 +114,8 @@ Expected<std::unique_ptr<TestClient>> TestClient::launchCustom(StringRef Log, Ar
   // Accept().
   Info.SetMonitorProcessCallback(&ProcessLaunchInfo::NoOpMonitorCallback);
 
+  if (disable_stdio)
+    Info.GetFlags().Set(lldb::eLaunchFlagDisableSTDIO);
   status = Host::LaunchProcess(Info);
   if (status.Fail())
     return status.ToError();

lldb/unittests/tools/lldb-server/tests/TestClient.h

@@ -48,8 +48,9 @@ class TestClient
   /// using this for generic tests, as the two stubs have different
   /// command-line interfaces.
   static llvm::Expected<std::unique_ptr<TestClient>>
-  launchCustom(llvm::StringRef Log, llvm::ArrayRef<llvm::StringRef> ServerArgs, llvm::ArrayRef<llvm::StringRef> InferiorArgs);
-
+  launchCustom(llvm::StringRef Log, bool disable_stdio,
+               llvm::ArrayRef<llvm::StringRef> ServerArgs,
+               llvm::ArrayRef<llvm::StringRef> InferiorArgs);
 
   ~TestClient() override;
   llvm::Error SetInferior(llvm::ArrayRef<std::string> inferior_args);