From fa14310c41827060a3cf1ccd3e14e2d91edbce2c Mon Sep 17 00:00:00 2001
From: Maxime Gimeno <maxime.gimeno@gmail.com>
Date: Fri, 31 Jan 2020 16:00:42 +0100
Subject: [PATCH] Add a test

---
 Convex_hull_3/include/CGAL/convex_hull_3.h    |  8 +++--
 .../Convex_hull_3/test_ch_3_ambiguity.cpp     | 32 +++++++++++++++++++
 2 files changed, 38 insertions(+), 2 deletions(-)
 create mode 100644 Convex_hull_3/test/Convex_hull_3/test_ch_3_ambiguity.cpp

diff --git a/Convex_hull_3/include/CGAL/convex_hull_3.h b/Convex_hull_3/include/CGAL/convex_hull_3.h
index 22f1222c204..ef4267cf286 100644
--- a/Convex_hull_3/include/CGAL/convex_hull_3.h
+++ b/Convex_hull_3/include/CGAL/convex_hull_3.h
@@ -37,6 +37,7 @@
 #include <memory>
 #include <list>
 #include <vector>
+#include <type_traits>
 #include <boost/bind.hpp>
 #include <boost/next_prior.hpp>
 #include <boost/type_traits/is_floating_point.hpp>
@@ -51,6 +52,7 @@
 #include <CGAL/boost/graph/Euler_operations.h>
 #include <CGAL/boost/iterator/transform_iterator.hpp>
 #include <CGAL/boost/graph/named_params_helper.h>
+#include <CGAL/is_iterator.h>
 
 #include <boost/unordered_map.hpp>
 
@@ -1038,7 +1040,10 @@ void convex_hull_3(InputIterator first, InputIterator beyond,
 
 template <class InputIterator, class Polyhedron_3>
 void convex_hull_3(InputIterator first, InputIterator beyond,
-                   Polyhedron_3& polyhedron)
+                   Polyhedron_3& polyhedron,
+                   typename std::enable_if<
+                     CGAL::is_iterator<InputIterator>::value
+                   >::type* =0) //workaround to avoid ambiguity with next overload.
 {
    typedef typename std::iterator_traits<InputIterator>::value_type Point_3;
    typedef typename internal::Convex_hull_3::Default_traits_for_Chull_3<Point_3, Polyhedron_3>::type Traits;
@@ -1056,7 +1061,6 @@ void convex_hull_3(const VertexListGraph& g,
   Vpmap vpm = CGAL::parameters::choose_parameter(CGAL::parameters::get_parameter(np, internal_np::vertex_point),
                                         get_const_property_map(boost::vertex_point, g));
 
-    
     Vpmap_fct v2p(vpm);
   convex_hull_3(
     boost::make_transform_iterator(vertices(g).begin(), v2p),
diff --git a/Convex_hull_3/test/Convex_hull_3/test_ch_3_ambiguity.cpp b/Convex_hull_3/test/Convex_hull_3/test_ch_3_ambiguity.cpp
new file mode 100644
index 00000000000..4091ec56265
--- /dev/null
+++ b/Convex_hull_3/test/Convex_hull_3/test_ch_3_ambiguity.cpp
@@ -0,0 +1,32 @@
+#include <CGAL/Exact_predicates_inexact_constructions_kernel.h>
+#include <CGAL/Polyhedron_3.h>
+#include <CGAL/Surface_mesh.h>
+#include <CGAL/convex_hull_3.h>
+#include <vector>
+#include <fstream>
+
+
+typedef CGAL::Exact_predicates_inexact_constructions_kernel  K;
+typedef CGAL::Polyhedron_3<K>                     Polyhedron_3;
+typedef K::Point_3                                Point_3;
+typedef CGAL::Surface_mesh<Point_3>               Surface_mesh;
+
+
+int main(int argc, char* argv[])
+{
+  std::ifstream in( (argc>1)? argv[1] : "data/cross.off");
+  
+  Surface_mesh poly;
+  if(!(in >> poly))
+  {
+    std::cerr<<"Could not find input file."<<std::endl;
+    return 1;
+  }
+  
+  Surface_mesh chull;
+  // compute convex hull
+  auto np = CGAL::parameters::all_default();
+  CGAL::convex_hull_3(poly, chull, np);
+  std::cout << "The convex hull contains " << chull.number_of_vertices() << " vertices" << std::endl;
+  return 0;
+}