[ntuple] Refactor out AddAuxiliary

Author: enirolf

tree/ntuple/v7/inc/ROOT/RNTupleProcessor.hxx

@@ -563,15 +563,6 @@ private:
                         std::unique_ptr<RNTupleModel> primaryModel = nullptr,
                         std::vector<std::unique_ptr<RNTupleModel>> auxModels = {});
 
-   /////////////////////////////////////////////////////////////////////////////
-   /// \brief Add an auxiliary RNTuple to the processor.
-   ///
-   /// \param[in] auxNTuple The source specification (name and storage location) of the auxiliary RNTuple.
-   /// \param[in] joinFields The names of the fields used in the join.
-   /// \param[in] ntupleIdx The index of the ntuple according to fNTuples.
-   void
-   AddAuxiliary(const RNTupleOpenSpec &auxNTuple, const std::vector<std::string> &joinFields, std::size_t ntupleIdx);
-
    /////////////////////////////////////////////////////////////////////////////
    /// \brief Connect all fields, once the primary and all auxiliary RNTuples have been added.
    void ConnectFields();

tree/ntuple/v7/src/RNTupleProcessor.cxx

@@ -351,6 +351,8 @@ ROOT::Experimental::RNTupleJoinProcessor::RNTupleJoinProcessor(const RNTupleOpen
 
    for (const auto &auxNTuple : auxNTuples) {
       fAuxiliaryPageSources.emplace_back(Internal::RPageSource::Create(auxNTuple.fNTupleName, auxNTuple.fStorage));
+      if (!joinFields.empty())
+         fJoinTables.emplace_back(Internal::RNTupleJoinTable::Create(joinFields));
    }
 
    if (!primaryModel)
@@ -371,12 +373,6 @@ ROOT::Experimental::RNTupleJoinProcessor::RNTupleJoinProcessor(const RNTupleOpen
       auto &field = value.GetField();
       const auto &fieldName = field.GetQualifiedFieldName();
 
-      auto isAuxParent = std::find_if(auxNTuples.cbegin(), auxNTuples.cend(), [&fieldName](const RNTupleOpenSpec &n) {
-         return fieldName.substr(0, n.fNTupleName.size()) == n.fNTupleName;
-      });
-      if (isAuxParent != auxNTuples.end())
-         continue;
-
       // If the model provided by the user has a default entry, use the value pointers from the default entry of the
       // model that was passed to this constructor. This way, the pointers returned by RNTupleModel::MakeField can be
       // used in the processor loop to access the corresponding field values.
@@ -385,11 +381,18 @@ ROOT::Experimental::RNTupleJoinProcessor::RNTupleJoinProcessor(const RNTupleOpen
          fEntry->BindValue(fieldName, valuePtr);
       }
 
-      fFieldContexts.try_emplace(fieldName, field.Clone(fieldName), fEntry->GetToken(fieldName));
-   }
+      auto auxNTupleName = std::find_if(auxNTuples.cbegin(), auxNTuples.cend(), [&fieldName](const RNTupleOpenSpec &n) {
+         return fieldName.substr(0, n.fNTupleName.size()) == n.fNTupleName;
+      });
 
-   for (unsigned i = 0; i < auxNTuples.size(); ++i) {
-      AddAuxiliary(auxNTuples[i], joinFields, i + 1 /* ntupleIdx */);
+      if (auxNTupleName == auxNTuples.end()) {
+         fFieldContexts.try_emplace(fieldName, field.Clone(field.GetFieldName()), fEntry->GetToken(fieldName));
+      } else if (fieldName != auxNTupleName->fNTupleName) {
+         // Add 1 because we also have to take into account the primary ntuple.
+         auto ntupleIdx = std::distance(auxNTuples.begin(), auxNTupleName) + 1;
+         fFieldContexts.try_emplace(fieldName, field.Clone(field.GetFieldName()), fEntry->GetToken(fieldName),
+                                    ntupleIdx);
+      }
    }
 }
 
@@ -436,32 +439,6 @@ void ROOT::Experimental::RNTupleJoinProcessor::SetModel(std::unique_ptr<RNTupleM
    fModel->Freeze();
 }
 
-void ROOT::Experimental::RNTupleJoinProcessor::AddAuxiliary(const RNTupleOpenSpec &auxNTuple,
-                                                            const std::vector<std::string> &joinFields,
-                                                            std::size_t ntupleIdx)
-{
-   assert(fNEntriesProcessed == 0 && "cannot add auxiliary ntuples after processing has started");
-
-   auto &auxParentField = fModel->GetConstField(auxNTuple.fNTupleName);
-
-   for (const auto &field : auxParentField.GetConstSubfields()) {
-      // If the model was provided by the user and it has a default entry, use the value pointers from the entry in
-      // the entry managed by the processor. This way, the pointers returned by RNTupleModel::MakeField can be used
-      // in the processor loop to access the corresponding field values.
-      if (!fModel->IsBare()) {
-         auto valuePtr = fModel->GetDefaultEntry().GetPtr<void>(field->GetQualifiedFieldName());
-         fEntry->BindValue(field->GetQualifiedFieldName(), valuePtr);
-      }
-
-      auto token = fEntry->GetToken(field->GetQualifiedFieldName());
-      fFieldContexts.try_emplace(field->GetQualifiedFieldName(), field->Clone(field->GetFieldName()), token, ntupleIdx);
-   }
-
-   // If no join fields have been specified, an aligned join is assumed and an join table won't be created.
-   if (!joinFields.empty())
-      fJoinTables.emplace_back(Internal::RNTupleJoinTable::Create(joinFields));
-}
-
 void ROOT::Experimental::RNTupleJoinProcessor::ConnectFields()
 {
    for (auto &[_, fieldContext] : fFieldContexts) {