[tree] Small cleanups in TEventList.

- Remove unused headers.
- Use member initialisers to clean up constructors.
- Apply clang-tidy/clang-format fixes for member init.

Author: hageboeck

tree/tree/inc/TEventList.h

@@ -31,15 +31,15 @@ class TCollection;
 class TEventList : public TNamed {
 
 protected:
-   Int_t            fN;           ///<  Number of elements in the list
-   Int_t            fSize;        ///<  Size of array
-   Int_t            fDelta;       ///<  Increment size
-   bool             fReapply;     ///<  If true, TTree::Draw will 'reapply' the original cut
-   Long64_t        *fList;        ///<[fN]Array of elements
-   TDirectory      *fDirectory;   ///<! Pointer to directory holding this tree
+   Int_t fN = 0;                     ///<  Number of elements in the list
+   Int_t fSize = 100;                ///<  Size of array
+   Int_t fDelta = 100;               ///<  Increment size
+   bool fReapply = false;            ///<  If true, TTree::Draw will 'reapply' the original cut
+   Long64_t *fList = nullptr;        ///<[fN]Array of elements
+   TDirectory *fDirectory = nullptr; ///<! Pointer to directory holding this tree
 
 public:
-   TEventList();
+   TEventList() = default;
    TEventList(const char *name, const char *title="",Int_t initsize=0, Int_t delta = 0);
    TEventList(const TEventList &list);
              ~TEventList() override;

tree/tree/src/TEventList.cxx

@@ -50,66 +50,49 @@ the TEventList object created in the above commands:
 #include "TBuffer.h"
 #include "TCut.h"
 #include "TDirectory.h"
-#include "TList.h"
-#include "TMath.h"
-#include "strlcpy.h"
-#include "snprintf.h"
+#include "TCollection.h"
+#include "TMathBase.h"
+#include "TROOT.h"
 
-
-////////////////////////////////////////////////////////////////////////////////
-/// Default constructor for a EventList.
-
-TEventList::TEventList(): TNamed()
-{
-   fN          = 0;
-   fSize       = 100;
-   fDelta      = 100;
-   fList       = nullptr;
-   fDirectory  = nullptr;
-   fReapply    = false;
-}
+#include <algorithm>
 
 ////////////////////////////////////////////////////////////////////////////////
 /// Create a EventList.
 ///
 /// This Eventlist is added to the list of objects in current directory.
 
 TEventList::TEventList(const char *name, const char *title, Int_t initsize, Int_t delta)
-  :TNamed(name,title), fReapply(false)
+   : TNamed(name, title), fSize(std::max(100, initsize)), fDelta(std::max(100, delta))
 {
-   fN = 0;
-   if (initsize > 100) fSize  = initsize;
-   else                fSize  = 100;
-   if (delta > 100)    fDelta = delta;
-   else                fDelta = 100;
-   fList       = nullptr;
-   fDirectory  = gDirectory;
-   if (fDirectory) fDirectory->Append(this);
+   if (ROOT::Experimental::ObjectAutoRegistrationEnabled()) {
+      fDirectory = gDirectory;
+      if (fDirectory)
+         fDirectory->Append(this);
+   }
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 /// Copy constructor.
 
-TEventList::TEventList(const TEventList &list) : TNamed(list)
+TEventList::TEventList(const TEventList &list)
+   : TNamed(list),
+     fN(list.fN),
+     fSize(list.fSize),
+     fDelta(list.fDelta),
+     fReapply(list.fReapply),
+     fList(new Long64_t[fSize])
 {
-   fN     = list.fN;
-   fSize  = list.fSize;
-   fDelta = list.fDelta;
-   fList  = new Long64_t[fSize];
-   for (Int_t i=0; i<fN; i++)
-      fList[i] = list.fList[i];
-   fReapply = list.fReapply;
-   fDirectory = nullptr;
+   std::copy(list.fList, list.fList + list.fN, fList);
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 /// Default destructor for a EventList.
 
 TEventList::~TEventList()
 {
-   delete [] fList;  fList = nullptr;
-   if (fDirectory) fDirectory->Remove(this);
-   fDirectory  = nullptr;
+   delete[] fList;
+   if (fDirectory)
+      fDirectory->Remove(this);
 }
 
 ////////////////////////////////////////////////////////////////////////////////