Merge branch 'TP.CreateTransient' into 'master'

Add helper class CreateTransient to TPConverterBase

See merge request !2807

Database/TPTools/TPTools/TPConverter.h

@@ -470,6 +470,25 @@ protected:
 
 // --------------------------------------------------------------
 
+namespace TPCnv {
+
+/** @class  TPCnv::CreateTransient
+    Helper class to make specializing the creation of transient objects
+    in the TPConverterBase::createTransient() easier.
+
+    Provide specialization before definition of your T/P converter for transient typeTRANS
+    The final T/P converter can still overwrite its whole createTransient() method 
+*/
+   template<class TRANS>
+   class CreateTransient  {
+      public:
+      static std::unique_ptr<TRANS>  create() { return std::make_unique<TRANS>(); }
+   };
+
+} // namespace TPCnv
+
+
+
 // Base converter template for polymorphic types
 
 // Converters for objects in the same inheritance tree must share the same

Database/TPTools/TPTools/TPConverter.icc

@@ -62,10 +62,13 @@ toPersistent_impl( const TRANS *trans, MsgStream &log )
 
 template< class TRANS_BASE, class TRANS, class PERS >
 TRANS* TPPolyCnvBase<TRANS_BASE, TRANS, PERS>::
-createTransient(const PERS* persObj, MsgStream &log) {
-   std::unique_ptr<TRANS>	trans(new TRANS());
+createTransient(const PERS* persObj, MsgStream &log)
+{
+   // this is by default equivalent to 'new TRANS()'
+   std::unique_ptr<TRANS> trans = TPCnv::CreateTransient<TRANS>::create();
+   
    this->persToTrans(persObj, trans.get(), log);
-   return(trans.release());
+   return( trans.release() );
 }