[core] Add test for ROOT-3594

root/io/tree/CMakeLists.txt

@@ -5,3 +5,6 @@
 #
 #-------------------------------------------------------------------------------
 ROOTTEST_ADD_OLDTEST()
+
+ROOTTEST_ADD_TEST(trefTest
+                  MACRO trefTest.C+)

root/io/tree/trefTest.C

@@ -0,0 +1,148 @@
+// This is a test included with minimal editing from
+// item ROOT-3594
+
+#include "ROOT/TProcessExecutor.hxx"
+
+#include "TClonesArray.h"
+#include "TFile.h"
+#include "TH1F.h"
+#include "TRefArray.h"
+#include "TTree.h"
+#include "TSystem.h"
+
+#include <iostream>
+
+class ObjA : public TObject {
+public:
+   UInt_t    fObjAVal;
+   TRefArray fObjB;
+   void      Clear(Option_t *)
+   {
+      fObjAVal = 0;
+      fObjB.Clear();
+   }
+
+   ClassDef(ObjA, 1);
+};
+
+class ObjB : public TObject {
+public:
+   UInt_t fObjBVal;
+   void   Clear(Option_t *) { fObjBVal = 0; }
+
+   ClassDef(ObjB, 1);
+};
+
+class Top : public TObject {
+public:
+   Top()
+   {
+      fObjAArray = new TClonesArray(ObjA::Class(), 10);
+      fObjBArray = new TClonesArray(ObjB::Class(), 10);
+   }
+   ~Top()
+   {
+      delete fObjAArray;
+      delete fObjBArray;
+   }
+
+   TClonesArray *fObjAArray; //->
+   TClonesArray *fObjBArray; //->
+   void          Clear(Option_t          */*opt*/ = "")
+   {
+      fObjAArray->Clear("C");
+      fObjBArray->Clear("C");
+   }
+
+   ClassDef(Top, 1);
+};
+
+bool fpCompare(double val, double ref)
+{
+   return 0.00001 > fabs(val - ref);
+}
+
+const char *gTheFileName = "trefTest.root";
+
+int createfile()
+{
+   Top  *atop = new Top();
+   TFile afile(gTheFileName, "recreate");
+   TTree tree("tree", "tree");
+
+   tree.BranchRef();
+   tree.Branch("top", atop);
+
+   for (size_t j = 0; j < 2; j++) {
+      Int_t saveNumber = TProcessID::GetObjectCount();
+      for (size_t i = 0; i < 10; i++) {
+         ObjA *a     = static_cast<ObjA *>(atop->fObjAArray->New(i));
+         ObjB *b     = static_cast<ObjB *>(atop->fObjBArray->New(i));
+         a->fObjAVal = i * 100 + j;
+         b->fObjBVal = i * 10 + j * 2;
+         a->fObjB.Add(b);
+      }
+      tree.Fill();
+      atop->Clear();
+      TProcessID::SetObjectCount(saveNumber);
+   }
+   tree.Write();
+   afile.Close();
+   return 0;
+}
+
+class CreateFileInProcessRAAI {
+public:
+   CreateFileInProcessRAAI()
+   {
+      // We need to create the file from another PID for the test to be effective
+      // NOTE: TSystem::AccessPathName returns true if the file can NOT be accessed
+      if (gSystem->AccessPathName(gTheFileName)) {
+         ROOT::TProcessExecutor pe(1);
+         std::vector<int> args = {0};
+         pe.Map([](){return createfile();}, 1);
+      }
+   }
+   ~CreateFileInProcessRAAI() { gSystem->Unlink(gTheFileName); }
+};
+
+int trefTest()
+{
+
+   CreateFileInProcessRAAI cfip_raai;
+
+   TFile afile(gTheFileName);
+   auto  tree = afile.Get<TTree>("tree");
+   tree->Draw("((ObjB*)(fObjAArray.fObjB.At(0))).fObjBVal >> hist(100, 0, 100)");
+   auto       hist     = (TH1F *)gDirectory->Get("hist");
+   std::cout << hist << std::endl;
+   const auto nEntries = hist->GetEntries();  // 20
+   const auto mean     = hist->GetMean();     // 46
+   const auto rms      = hist->GetRMS();      // 28.74021572639983
+   const auto skewness = hist->GetSkewness(); // 0.05219694055188104
+   const auto kurtosis = hist->GetKurtosis(); // -1.2194668103524087
+
+   int retcode = 0;
+   if (nEntries != 20) {
+      retcode++;
+      std::cerr << "Wrong number of entries: expected 20, obtained " << nEntries << std::endl;
+   }
+   if (!fpCompare(mean, 46.)) {
+      retcode++;
+      std::cerr << "Wrong mean: expected 46, obtained " << mean << std::endl;
+   }
+   if (!fpCompare(rms, 28.74021572639983)) {
+      retcode++;
+      std::cerr << "Wrong rms: expected 28.74021572639983, obtained " << rms << std::endl;
+   }
+   if (!fpCompare(skewness, 0.05219694055188104)) {
+      retcode++;
+      std::cerr << "Wrong skewness: expected 0.05219694055188104, obtained " << skewness << std::endl;
+   }
+   if (!fpCompare(kurtosis, -1.2194668103524087)) {
+      retcode++;
+      std::cerr << "Wrong kurtosis: expected -1.2194668103524087, obtained " << kurtosis << std::endl;
+   }
+
+   return retcode;
+}