Merge branch 'cherry-pick-11e991b0' into '2018-patches'

Propagate MR !191 from 2017-patches to 2018-patches

See merge request !194

Calo/CaloAssociators/src/CaloDigit2MCLinks2Table.cpp

@@ -71,6 +71,7 @@ protected:
     : GaudiAlgorithm ( name , pSvc ) 
     , m_inputs ( 1 , LHCb::CaloDigitLocation::Ecal      ) 
     , m_output ( "Relations/" + LHCb::CaloDigitLocation::Default ) 
+    , m_respectInputDigitLocation ( true ) 
   {
     declareProperty 
       ( "Inputs" , 
@@ -80,6 +81,17 @@ protected:
       ( "Output" , 
         m_output , 
         "TES-Output Location of Relation Table CaloDigit->MCParticle" ) ;
+    /*
+     * Problem: By default, this algorithm will ask the linker tables for links
+     * based on the index *and* location of the input digits. This means
+     * cloning digits and then running this algorithm on the clones won't work.
+     * Solution: Only associate digits based on their index, enabled by setting
+     * this property to false.
+     */
+    declareProperty 
+      ( "RespectInputDigitLocation" , 
+        m_respectInputDigitLocation , 
+        "If false, do not check that the location of the input digits match those defined in the linker table, only the index" ) ;
   } 
   /// virtual destructor (protected)
   virtual ~CaloDigit2MCLinks2Table() {}
@@ -100,6 +112,7 @@ private:
   typedef std::vector<std::string>  Inputs ;
   Inputs      m_inputs ;
   std::string m_output ;
+  bool        m_respectInputDigitLocation ;
   // ==========================================================================
 };
 // ============================================================================
@@ -150,7 +163,7 @@ StatusCode CaloDigit2MCLinks2Table::execute    ()
       if ( 0 == digit ) { continue ; }
       
       // use Linker
-      const LHCb::MCParticle* particle = linker.first( digit ) ;
+      const LHCb::MCParticle* particle = m_respectInputDigitLocation ? linker.first(digit) : linker.first(digit->index());
       if ( 0 == particle ) { continue ; }
       
       // use the auxillary container to be immune agains