cmState: Move snapshot creation to the cmake instance.

Don't create a snapshot in Initialize(), but leave the creation
responsibility to the cmake instance instead.  Previously, the
cmState would Initialize() in its constructor, and the cmake instance
would re-Initialize() during Configure().  The end result was the
same and there would be one snapshot present.  However, cmLocalGenerator
also created a snapshot on construction, and that one was used, leaving
the first snapshot unused, and potential for off-by-one errors.

Fix that by making the cmLocalGenerator use the existing snapshot
if it is top-level.  Add a CurrentSnapshot to the cmake instance and
populated it while configuring a directory.  This will eventually
replace the 'current local generator' concept.  Fix the GetParent
implementation to be able to return the first snapshot.

1 files changed, 2 insertions, 1 deletions

diff --git a/Source/cmake.cxx b/Source/cmake.cxx
index 1c9842e..3ef85b6 100644
--- a/Source/cmake.cxx
+++ b/Source/cmake.cxx
@@ -134,6 +134,7 @@ cmake::cmake()
 
   this->Policies = new cmPolicies();
   this->State = new cmState(this);
+  this->CurrentSnapshot = this->State->CreateSnapshot(cmState::Snapshot());
 
 #ifdef __APPLE__
   struct rlimit rlp;
@@ -185,7 +186,7 @@ cmake::~cmake()
 
 void cmake::CleanupCommandsAndMacros()
 {
-  this->State->Initialize();
+  this->State->Reset();
   this->State->RemoveUserDefinedCommands();
 }