Fix intermingling of test environments when tests run in parallel.

The SaveRestoreEnvironment helper object makes sure that the
original environment is restored immediately after the
StartProcess call returns rather than waiting for the end
of the test. When tests are executed in parallel, there is
no guarantee about the ordering of EndTest calls relative
to StartTest calls. In fact, it would be odd for them to
be nested nicely. Therefore, to avoid the corruption of
the calling ctest's environment, the original environment
must be restored before ForkProcess returns.

2 files changed, 6 insertions, 16 deletions

diff --git a/Source/CTest/cmCTestRunTest.cxx b/Source/CTest/cmCTestRunTest.cxx
index fe2437d..4c9675b 100644
--- a/Source/CTest/cmCTestRunTest.cxx
+++ b/Source/CTest/cmCTestRunTest.cxx
@@ -23,7 +23,6 @@ cmCTestRunTest::cmCTestRunTest(cmCTestTestHandler* handler)
 {
   this->CTest = handler->CTest;
   this->TestHandler = handler;
-  this->ModifyEnv = false;
   this->TestProcess = 0;
   this->TestResult.ExecutionTime =0;
   this->TestResult.ReturnValue = 0;
@@ -139,11 +138,6 @@ bool cmCTestRunTest::EndTest(size_t completed, size_t total, bool started)
     this->CompressOutput();
     }
 
-  //restore the old environment
-  if (this->ModifyEnv)
-    {
-    cmSystemTools::RestoreEnv(this->OrigEnv);
-    }
   this->WriteLogOutputTop(completed, total);
   std::string reason;
   bool passed = true;
@@ -593,9 +587,6 @@ bool cmCTestRunTest::ForkProcess(double testTimeOut,
   this->TestProcess->SetCommand(this->ActualCommand.c_str());
   this->TestProcess->SetCommandArguments(this->Arguments);
 
-  std::vector<std::string> origEnv;
-  this->ModifyEnv = (environment && environment->size()>0);
-
   // determine how much time we have
   double timeout = this->CTest->GetRemainingTimeAllowed() - 120;
   if (this->CTest->GetTimeOut() > 0 && this->CTest->GetTimeOut() < timeout)
@@ -618,9 +609,13 @@ bool cmCTestRunTest::ForkProcess(double testTimeOut,
 
   this->TestProcess->SetTimeout(timeout);
 
-  if (this->ModifyEnv)
+#ifdef CMAKE_BUILD_WITH_CMAKE
+  cmSystemTools::SaveRestoreEnvironment sre;
+#endif
+
+  if (environment && environment->size()>0)
     {
-    this->OrigEnv = cmSystemTools::AppendEnv(environment);
+    cmSystemTools::AppendEnv(environment);
     }
 
   return this->TestProcess->StartProcess();
diff --git a/Source/CTest/cmCTestRunTest.h b/Source/CTest/cmCTestRunTest.h
index 14fa2e5..d7d3a2f 100644
--- a/Source/CTest/cmCTestRunTest.h
+++ b/Source/CTest/cmCTestRunTest.h
@@ -77,14 +77,9 @@ private:
   //if this option is set to false.)
   //bool OptimizeForCTest;
 
-  //flag for whether the env was modified for this run
-  bool ModifyEnv;
-
   bool UsePrefixCommand;
   std::string PrefixCommand;
 
-  //stores the original environment if we are modifying it
-  std::vector<std::string> OrigEnv;
   std::string ProcessOutput;
   std::string CompressedOutput;
   double CompressionRatio;