[Exp PyROOT] Pass file open mode as parameter

bindings/pyroot_experimental/PyROOT/test/TreeHelper.h

@@ -11,9 +11,10 @@ struct MyStruct {
 // - vectorb: branch of type `std::vector<double>`, size `arraysize`
 // - structb: struct branch of type `MyStruct`
 // - structleafb: struct branch of type `MyStruct`, created as a leaf list
-void CreateTTree(const char *filename, const char *treename, int nentries, int arraysize, int more)
+void CreateTTree(const char *filename, const char *treename, int nentries, int arraysize, int more,
+                 const char* openmode)
 {
-   TFile f(filename, "RECREATE");
+   TFile f(filename, openmode);
    TTree t(treename, "Test tree");
 
    // Float branch

bindings/pyroot_experimental/PyROOT/test/ttree_branch_attr.py

@@ -20,7 +20,12 @@ class TTreeBranchAttr(unittest.TestCase):
     @classmethod
     def setUpClass(cls):
         ROOT.gInterpreter.Declare('#include "TreeHelper.h"')
-        ROOT.CreateTTree(cls.filename, cls.treename, cls.nentries, cls.arraysize, cls.more)
+        ROOT.CreateTTree(cls.filename,
+                         cls.treename,
+                         cls.nentries,
+                         cls.arraysize,
+                         cls.more,
+                         "RECREATE")
 
     # Helper
     def get_file_and_tree(self):

bindings/pyroot_experimental/PyROOT/test/ttree_iterable.py

@@ -23,7 +23,12 @@ class TTreeIterable(unittest.TestCase):
     @classmethod
     def setUpClass(cls):
         ROOT.gInterpreter.Declare('#include "TreeHelper.h"')                                          
-        ROOT.CreateTTree(cls.filename, cls.treename, cls.nentries, cls.arraysize, cls.more)
+        ROOT.CreateTTree(cls.filename,
+                         cls.treename,
+                         cls.nentries,
+                         cls.arraysize,
+                         cls.more,
+                         "RECREATE")
 
     # Helper
     def get_file_and_tree(self):

bindings/pyroot_experimental/PyROOT/test/ttree_setbranchaddress.py

@@ -27,7 +27,12 @@ class TTreeSetBranchAddress(unittest.TestCase):
     @classmethod
     def setUpClass(cls):
         ROOT.gInterpreter.Declare('#include "TreeHelper.h"')
-        ROOT.CreateTTree(cls.filename, cls.treename, cls.nentries, cls.arraysize, cls.more)
+        ROOT.CreateTTree(cls.filename,
+                         cls.treename,
+                         cls.nentries,
+                         cls.arraysize,
+                         cls.more,
+                         "RECREATE")
 
     # Helper
     def get_file_tree_and_chain(self):