Don't do public accessor workarounds if not needed (#875)

Some public accessor hacks are now hidden behind preprocessor macros.
This will serve as a reminder to remove these workarounds in the far
future when combine doesn't support old ROOT versions anymore.

interface/utils.h

@@ -56,8 +56,10 @@ namespace utils {
 
     /// factorize a RooAbsReal
     void factorizeFunc(const RooArgSet &observables, RooAbsReal &pdf, RooArgList &obsTerms, RooArgList &otherTerms, bool keepDuplicates = true, bool debug=false);
+#if ROOT_VERSION_CODE < ROOT_VERSION(6,28,0)
     /// workaround for RooProdPdf::components()
     RooArgList factors(const RooProduct &prod) ;
+#endif
 
     /// Note: doesn't recompose Simultaneous pdfs properly, for that use factorizePdf method
     RooAbsPdf *makeObsOnlyPdf(RooStats::ModelConfig &model, const char *name="obsPdf") ;

src/CachingMultiPdf.cc

@@ -134,7 +134,11 @@ void cacheutils::CachingAddPdf::setIncludeZeroWeights(bool includeZeroWeights)
 cacheutils::CachingProduct::CachingProduct(const RooProduct &pdf, const RooArgSet &obs) :
     pdf_(&pdf)
 {
+#if ROOT_VERSION_CODE < ROOT_VERSION(6,28,0)
     const RooArgList & pdfs = utils::factors(pdf);
+#else
+    const RooArgList & pdfs = pdf.realComponents();
+#endif
     //std::cout << "Making a CachingProduct for " << pdf.GetName() << " with " << pdfs.getSize() << " pdfs, " << coeffs.getSize() << " coeffs." << std::endl;
     for (int i = 0, n = pdfs.getSize(); i < n; ++i) {
         RooAbsReal *pdfi = (RooAbsReal*) pdfs.at(i);

src/VectorizedHistFactoryPdfs.cc

@@ -81,24 +81,32 @@ cacheutils::VectorizedParamHistFunc::fill(std::vector<Double_t> &out) const
     }
 }
 
+#if ROOT_VERSION_CODE < ROOT_VERSION(6,30,0)
 namespace {
     class PiecewiseInterpolationWithAccessor : public PiecewiseInterpolation {
         public:
             PiecewiseInterpolationWithAccessor(const PiecewiseInterpolation &p) :
                 PiecewiseInterpolation(p) {}
-            const RooAbsReal & nominal() const { return _nominal.arg(); }
-            int getInterpCode(int i) const { return _interpCode[i]; }
+            const RooAbsReal* nominalHist() const { return &_nominal.arg(); }
+            const std::vector<int>&  interpolationCodes() const { return _interpCode; }
             bool positiveDefinite() const { return _positiveDefinite; }
     };
 }
+#endif
 
 cacheutils::CachingPiecewiseInterpolation::CachingPiecewiseInterpolation(const PiecewiseInterpolation &pdf, const RooArgSet &obs) :
     pdf_(&pdf)
 {
+#if ROOT_VERSION_CODE < ROOT_VERSION(6,30,0)
+    // Since ROOT 6.30, the public accessors are in upstream RooFit and we
+    // don't need this hack.
     PiecewiseInterpolationWithAccessor fixme(pdf);
+#else
+    auto& fixme = pdf;
+#endif
     const RooArgList & highList  = pdf.highList();
     const RooArgList & lowList   = pdf.lowList();
-    const RooAbsReal & nominal   = fixme.nominal(); 
+    const RooAbsReal & nominal   = *fixme.nominalHist();
     const RooArgList & coeffs = pdf.paramList();
     //std::cout << "Making a CachingPiecewiseInterpolation for " << pdf.GetName() << " with " << highList.getSize() << " pdfs, " << coeffs.getSize() << " coeffs." << std::endl;
     positiveDefinite_ = fixme.positiveDefinite();
@@ -109,7 +117,7 @@ cacheutils::CachingPiecewiseInterpolation::CachingPiecewiseInterpolation(const P
         RooAbsReal *pdfiLo = (RooAbsReal*) lowList.at(i);
         cachingPdfsLow_.push_back(makeCachingPdf(pdfiLo, &obs));
         coeffs_.push_back((RooAbsReal*) coeffs.at(i));
-        codes_.push_back(fixme.getInterpCode(i));
+        codes_.push_back(fixme.interpolationCodes()[i]);
         //std::cout << "      PiecewiseInterpolation Adding " << pdf.GetName() << "[" << i << "] Hi    : " << pdfiHi->ClassName() << " " << pdfiHi->GetName() << " using " << typeid(cachingPdfsHi_.back()).name() << std::endl;
         //std::cout << "      PiecewiseInterpolation Adding " << pdf.GetName() << "[" << i << "] Hi    : " << pdfiHi->ClassName() << " " << pdfiHi->GetName() << " using " << typeid(cachingPdfsHi_.back()).name() << std::endl;
         //std::cout << "      PiecewiseInterpolation Adding " << pdf.GetName() << "[" << i << "] Coeff : " << coeffs_.back()->ClassName() << " " << coeffs_.back()->GetName()  << std::endl;

src/utils.cc

@@ -43,7 +43,13 @@
 
 using namespace std;
 
+#if ROOT_VERSION_CODE < ROOT_VERSION(6,28,0)
+
 // This is needed to be able to factorize products in factorizeFunc, since RooProduct::components() strips duplicates
+//
+// Note: since ROOT 6.28.00, this workaround is not necessary more, because
+// there is direct public access to the _compRSet via
+// RooProduct::realComponents().
 namespace {
     class RooProductWithAccessors : public RooProduct {
         public:
@@ -61,6 +67,12 @@ namespace {
     };
 }
 
+RooArgList utils::factors(const RooProduct &prod) {
+    return ::RooProductWithAccessors(prod).realTerms();
+}
+
+#endif
+
 void utils::printRDH(RooAbsData *data) {
   std::vector<std::string> varnames, catnames;
   const RooArgSet *b0 = data->get();
@@ -224,9 +236,6 @@ void utils::factorizePdf(const RooArgSet &observables, RooAbsPdf &pdf, RooArgLis
 }
 
 
-RooArgList utils::factors(const RooProduct &prod) {
-    return ::RooProductWithAccessors(prod).realTerms();
-}
 void utils::factorizeFunc(const RooArgSet &observables, RooAbsReal &func, RooArgList &obsTerms, RooArgList &constraints, bool keepDuplicate, bool debug) {
     RooAbsPdf *pdf = dynamic_cast<RooAbsPdf *>(&func);
     if (pdf != 0) { 
@@ -236,7 +245,11 @@ void utils::factorizeFunc(const RooArgSet &observables, RooAbsReal &func, RooArg
     const std::type_info & id = typeid(func);
     if (id == typeid(RooProduct)) {
         RooProduct *prod = dynamic_cast<RooProduct *>(&func);
+#if ROOT_VERSION_CODE < ROOT_VERSION(6,28,0)
         RooArgList components(utils::factors(*prod));
+#else
+        RooArgList components(prod->realComponents());
+#endif
         //std::cout << "Function " << func.GetName() << " is a RooProduct with " << components.getSize() << " components." << std::endl;
         std::unique_ptr<TIterator> iter(components.createIterator());
         for (RooAbsReal *funci = (RooAbsReal *) iter->Next(); funci != 0; funci = (RooAbsReal *) iter->Next()) {