From f7fa19a07967537d35c01190face0c32fddec88e Mon Sep 17 00:00:00 2001
From: dmatetelki <denes.matetelki@emerson.com>
Date: Wed, 23 Sep 2015 16:31:12 +0200
Subject: [PATCH] Graph has equal and disjointUnion functions

---
 lib/graph/graph.hpp                  | 10 +++++++++
 lib/graph/priority_queue.hpp         |  7 +++++--
 test/graph/fixture.hpp               |  5 +++--
 test/graph/test_graph.cpp            | 31 ++++++++++++++++++++++++++++
 test/graph/test_graph_algorithms.cpp |  2 +-
 5 files changed, 50 insertions(+), 5 deletions(-)

diff --git a/lib/graph/graph.hpp b/lib/graph/graph.hpp
index 68be930..e4e29f8 100644
--- a/lib/graph/graph.hpp
+++ b/lib/graph/graph.hpp
@@ -73,6 +73,7 @@ public:
   Graph(const std::vector<V>& vertex_list);
   Graph(std::initializer_list<Edge> edge_list);
   Graph(const std::vector<Edge>& edge_list);
+  bool operator==(const Graph& o) const { return m_vertices == o.m_vertices; }
 
   void addVertex(const_reference data);
   void removeVertex(const_reference data);
@@ -169,6 +170,15 @@ inline std::vector<typename Graph<V>::Edge> edges(const Graph<V>& g)
   return retval;
 }
 
+template <typename V>
+inline Graph<V> disjointUnion(const Graph<V>& a, const Graph<V>& b) {
+  Graph<V> g(a);
+  for (const auto& e : edges(b))
+    g.addEdge(e.source, e.destination);
+
+  return g;
+}
+
 
 // Graph implementation
 
diff --git a/lib/graph/priority_queue.hpp b/lib/graph/priority_queue.hpp
index 9a5123a..2a2a58f 100644
--- a/lib/graph/priority_queue.hpp
+++ b/lib/graph/priority_queue.hpp
@@ -9,10 +9,13 @@
  * The priority queue based Dijkstra (shortest path) algorith requires the
  * modifyKey functionality, which the std::priority_queue does not have.
  *
- * @note modifyKey is very ineffective, since std::map is not a
+ * @note modifyKey is not very efficient, since std::map is not a
  * bidirectional map, looking up an element based on value is linear.
  *
- * @todo replace std::map with a Fibonacci heap to improve performance.
+ * But not terribly that bad either: keylookup is fast thou the iteration
+ * over elements with same key is linear.
+ *
+ * @todo replace std::map with a Fibonacci or Buffer heap to improve performance.
  */
 
 template <
diff --git a/test/graph/fixture.hpp b/test/graph/fixture.hpp
index 8a43fed..ebb0830 100644
--- a/test/graph/fixture.hpp
+++ b/test/graph/fixture.hpp
@@ -1,6 +1,8 @@
 #ifndef GRAPH_TEST_FIXTURE_HPP
 #define GRAPH_TEST_FIXTURE_HPP
 
+#include <graph/graph.hpp>
+
 #include <cmath>
 
 inline std::size_t hash_f(float f) { return std::hash<float>()(f); }
@@ -16,10 +18,9 @@ struct float2 {
 };
 
 inline bool operator ==(const float2& v1, const float2& v2) { return v1.x == v2.x && v1.y == v2.y; }
+inline bool operator !=(const float2& v1, const float2& v2) { return !(v1 == v2); }
 inline float pow2(float f) { return f*f; }
 inline float dist(const float2& v1, const float2& v2) { return sqrt(pow2(v2.x - v1.x) + pow2(v2.y - v1.y)); }
-// inline float dist(const float2& v1, const float2& v2) { return abs(v2.x - v1.x) + abs(v2.y - v1.y); }
-
 
 
 namespace std {
diff --git a/test/graph/test_graph.cpp b/test/graph/test_graph.cpp
index f23d140..f4aa0eb 100644
--- a/test/graph/test_graph.cpp
+++ b/test/graph/test_graph.cpp
@@ -4,8 +4,39 @@
 
 #include "fixture.hpp"
 
+#include <map>
+#include <type_traits>
+
 TEST_CASE( "Graph creation", "[graph][data_structure]" ) {
 
+  SECTION("rule of 3+2") {
+    REQUIRE ( std::is_default_constructible<Graph<int> >::value == true);
+    REQUIRE ( std::is_copy_constructible<Graph<int> >::value == true);
+    REQUIRE ( std::is_move_constructible<Graph<int> >::value == true);
+
+    Graph<int> g1 = { 1, 2, 3 };
+    Graph<int> g2 = { 4, 5, 6 };
+    Graph<int> g3(g1); // cctor
+    REQUIRE ( g3 == g1 );
+
+    // catch does not likes templates in REQUIRE
+    constexpr bool is_assignable = std::is_assignable<Graph<int>, Graph<int> >::value;
+    REQUIRE ( is_assignable == true);
+    REQUIRE ( std::is_copy_assignable<Graph<int> >::value == true);
+    REQUIRE ( std::is_move_assignable<Graph<int> >::value == true);
+
+    g3 = g2; // assign
+    REQUIRE ( g3 == g2 );
+
+    Graph<int> g4 = g1; // cctor
+    Graph<int> g5 = std::move(g1); // move ctor, g1 become invalid
+    REQUIRE ( g4 == g5 );
+
+    Graph<int> g6 = g2; // cctor
+    g1 = std::move(g2); // move assign
+    REQUIRE ( g1 == g6 );
+  }
+
   SECTION("Initial state") {
     Graph<int> g;
     REQUIRE( empty(g) == true );
diff --git a/test/graph/test_graph_algorithms.cpp b/test/graph/test_graph_algorithms.cpp
index 4379bbd..163d328 100644
--- a/test/graph/test_graph_algorithms.cpp
+++ b/test/graph/test_graph_algorithms.cpp
@@ -103,7 +103,7 @@ TEST_CASE("Graph algorithms, small", "[graph][algorithm][dijkstra]" ) {
 
 TEST_CASE_METHOD(Fixture<float2>, "Graph algorithms, big graph", "[graph][algorithm][dijkstra][performance]" ) {
 
-  constexpr std::size_t number_of_rows = 300;
+  constexpr std::size_t number_of_rows = 1000;
   constexpr std::size_t number_of_columns = number_of_rows;
 
   Fixture<float2>::initOnce(number_of_rows, number_of_columns);