Add tests for the flavor tagging EDM

This moves some tests for the flavor tagging EDM into FlavourTaggingTests to consolidate them.

Also adds a new test focused on checking the links to associated particles.

PhysicsAnalysis/JetTagging/FlavourTaggingTests/util/test-associated-iparticles.cxx

+// Copyright (C) 2002-2022 CERN for the benefit of the ATLAS collaboration
+
+#include "xAODRootAccess/Init.h"
+#include "xAODRootAccess/tools/ReturnCheck.h"
+#include "xAODRootAccess/TEvent.h"
+#include "xAODJet/JetContainer.h"
+#include "xAODTracking/TrackParticle.h"
+
+#include "AsgMessaging/MessageCheck.h"
+
+#include "TFile.h"
+#include "TTree.h"
+#include "TError.h"
+
+int main ATLAS_NOT_THREAD_SAFE (int argc, char *argv[]) {
+
+  ANA_CHECK_SET_TYPE (int);
+  using namespace asg::msgUserCode;
+  gErrorIgnoreLevel = kError;
+
+  if (argc != 4) {
+    std::cerr << "usage: " << argv[0] << ": <DAOD> <jet collection> <associated collection>"
+              << "\n\n"
+              << "Return codes:\n"
+              << " -1: usage error\n"
+              << "  1: broken association\n"
+              << "  2: some associated objects are not tracks\n"
+              << "  0: association works, is all tracks" << std::endl;
+    return -1;
+  }
+  std::string file = argv[1];
+  std::string jets_name = argv[2];
+  std::string linked_particles_name = argv[3];
+
+  // The name of the application:
+  const std::string APP_NAME = "TestAssociatedIparticles";
+
+  // Set up the environment:
+  ANA_CHECK( xAOD::Init() );
+
+  // Set up the event object:
+  xAOD::TEvent event(xAOD::TEvent::kClassAccess);
+
+  // Open the file:
+  std::unique_ptr<TFile> ifile(TFile::Open(file.c_str(), "READ"));
+  if ( ! ifile.get() || ifile->IsZombie()) {
+    std::cerr << "Couldn't open file: " << file << std::endl;
+    return 1;
+  }
+
+  // Connect the event object to it:
+  ANA_CHECK( event.readFrom(ifile.get()) );
+
+  unsigned long long nbad = 0;
+  unsigned long long ngood = 0;
+  unsigned long long nIParticle = 0;
+  unsigned long long nTrack = 0;
+  unsigned long long entries = event.getEntries();
+  for (unsigned long long entry = 0; entry < entries; ++entry) {
+    // Load the event:
+    if (event.getEntry(entry) < 0) {
+      std::cerr << "Couldn't load entry " << entry << " from file"
+                << file << std::endl;
+      return 1;
+    }
+    const xAOD::JetContainer *jets = nullptr;
+    ANA_CHECK( event.retrieve(jets, jets_name) );
+    for (const xAOD::Jet *const jet : *jets) {
+      std::vector<const xAOD::IParticle*> particles;
+      if (!jet->getAssociatedObjects(linked_particles_name, particles)){
+        nbad++;
+      } else {
+        ngood++;
+        nIParticle += particles.size();
+        for (const auto* part: particles) {
+          if (dynamic_cast<const xAOD::TrackParticle*>(part)) {
+            nTrack++;
+          }
+        }
+      }
+    }
+  }
+  std::cout << "Summary: found " << ngood << " out of " << nbad + ngood <<" jets with valid links to associated particles " << std::endl;
+  std::cout << "Found " << nIParticle << " associated xAOD::IParticles, "
+            << nTrack << " of which were tracks" << std::endl;
+  if (nbad > 0) return 1;
+  if (nIParticle > nTrack) return 2;
+  return 0;
+}