From 14b8930f791318365a55ac48d3ff226d8554ea7a Mon Sep 17 00:00:00 2001
From: Laurent Rineau <laurent.rineau@cgal.org>
Date: Fri, 31 Jan 2020 14:49:31 +0100
Subject: [PATCH] Fix a clang-tidy warning by using nullptr instead of 0

---
 Spatial_sorting/include/CGAL/spatial_sort.h            |  3 ++-
 TDS_2/include/CGAL/Triangulation_data_structure_2.h    |  2 +-
 .../include/CGAL/Constrained_triangulation_2.h         | 10 +++++-----
 Triangulation_2/include/CGAL/Triangulation_2.h         |  6 +++---
 4 files changed, 11 insertions(+), 10 deletions(-)

diff --git a/Spatial_sorting/include/CGAL/spatial_sort.h b/Spatial_sorting/include/CGAL/spatial_sort.h
index 8aa44ff6af7..891889e4b50 100644
--- a/Spatial_sorting/include/CGAL/spatial_sort.h
+++ b/Spatial_sorting/include/CGAL/spatial_sort.h
@@ -118,7 +118,8 @@ void spatial_sort (RandomAccessIterator begin, RandomAccessIterator end,
     typedef std::iterator_traits<RandomAccessIterator> ITraits;
     typedef typename ITraits::value_type               value_type;
 
-    internal::spatial_sort(begin, end, k, policy, static_cast<value_type *> (0),
+    internal::spatial_sort(begin, end, k, policy,
+                           static_cast<value_type *> (nullptr),
 			   threshold_hilbert,threshold_multiscale,ratio);
 }
 
diff --git a/TDS_2/include/CGAL/Triangulation_data_structure_2.h b/TDS_2/include/CGAL/Triangulation_data_structure_2.h
index 9eb67f85818..680ab3579e9 100644
--- a/TDS_2/include/CGAL/Triangulation_data_structure_2.h
+++ b/TDS_2/include/CGAL/Triangulation_data_structure_2.h
@@ -822,7 +822,7 @@ is_edge(Vertex_handle va, Vertex_handle vb,
 {
   Face_handle fc = va->face(); 
   Face_handle start = fc;
-  if (fc == 0) return false;
+  if (fc == nullptr) return false;
   int inda, indb;
   do {
     inda=fc->index(va);
diff --git a/Triangulation_2/include/CGAL/Constrained_triangulation_2.h b/Triangulation_2/include/CGAL/Constrained_triangulation_2.h
index 4805a68e33e..9fe6473e79a 100644
--- a/Triangulation_2/include/CGAL/Constrained_triangulation_2.h
+++ b/Triangulation_2/include/CGAL/Constrained_triangulation_2.h
@@ -556,7 +556,7 @@ public:
     {
       Edge_circulator ec=incident_edges(v), done(ec);
       bool are_there = false;
-      if (ec == 0) return are_there;
+      if (ec == nullptr) return are_there;
       do {
 	if(is_constrained(*ec)) {
 	  *out++ = *ec;
@@ -572,7 +572,7 @@ public:
  OutputItEdges  incident_constraints(Vertex_handle v, 
 				      OutputItEdges out) const {
    Edge_circulator ec=incident_edges(v), done(ec);
-   if (ec == 0) return  out;
+   if (ec == nullptr) return  out;
    do {
      if(is_constrained(*ec))    *out++ = *ec;
      ec++;
@@ -1064,7 +1064,7 @@ update_constraints_incident(Vertex_handle va,
     //dimension() ==2
     int cwi, ccwi, indf;
     Face_circulator fc=incident_faces(va), done(fc);  
-    CGAL_triangulation_assertion(fc != 0);
+    CGAL_triangulation_assertion(fc != nullptr);
     do {
       indf = fc->index(va);
       cwi=cw(indf);
@@ -1091,7 +1091,7 @@ clear_constraints_incident(Vertex_handle va)
  Edge_circulator ec=incident_edges(va), done(ec);
  Face_handle f;
  int indf;
-  if ( ec != 0){
+  if ( ec != nullptr){
     do {
       f = (*ec).first ;
       indf = (*ec).second;
@@ -1278,7 +1278,7 @@ Constrained_triangulation_2<Gt,Tds,Itag>::
 remove_incident_constraints(Vertex_handle v)
 {
    Edge_circulator ec=incident_edges(v), done(ec);
-   if (ec == 0) return;
+   if (ec == nullptr) return;
    do {
 	if(is_constrained(*ec)) { remove_constrained_edge((*ec).first,
 						   (*ec).second);}
diff --git a/Triangulation_2/include/CGAL/Triangulation_2.h b/Triangulation_2/include/CGAL/Triangulation_2.h
index de91b826848..62c1d72902d 100644
--- a/Triangulation_2/include/CGAL/Triangulation_2.h
+++ b/Triangulation_2/include/CGAL/Triangulation_2.h
@@ -625,7 +625,7 @@ std::ptrdiff_t insert(InputIterator first, InputIterator last,
          typename std::iterator_traits<InputIterator>::value_type,
          Point
          >
-         >::type* = NULL)
+         >::type* = nullptr)
 #else
   template < class InputIterator >
   std::ptrdiff_t
@@ -1013,7 +1013,7 @@ includes_edge(Vertex_handle va, Vertex_handle vb,
   Orientation orient;
   int indv;
   Edge_circulator ec = incident_edges(va), done(ec);
-  if (ec != 0) {
+  if (ec != nullptr) {
     do {
       //find the index of the other vertex of *ec
       indv = 3 - ((*ec).first)->index(va) - (*ec).second ;
@@ -2602,7 +2602,7 @@ march_locate_2D_LFC(Face_handle start,
   }else {
     lfc = Line_face_circulator(start->vertex(0), this, t);
   }
-  if(lfc==0 || lfc.collinear_outside()){
+  if(lfc==nullptr || lfc.collinear_outside()){
     // point t lies outside or on the convex hull
     // we walk on the convex hull to find it out
     Face_circulator fc = incident_faces(infinite_vertex());