Index: src/test/Makefile.am
===================================================================
--- src/test/Makefile.am	(revision 800)
+++ src/test/Makefile.am	(revision 810)
@@ -3,11 +3,18 @@
 noinst_HEADERS = test_tools.h graph_test.h
 
-check_PROGRAMS = test_tools_pass test_tools_fail \
+check_PROGRAMS = \
+	bfs_test \
+	dfs_test \
+	dijkstra_test \
+	error_test \
 	graph_test \
-	dijkstra_test bfs_test dfs_test \
-	minlengthpaths_test mincostflows_test \
-	unionfind_test xy_test \
+	kruskal_test \
+	mincostflows_test \
+	minlengthpaths_test \
+	test_tools_fail \
+	test_tools_pass \
 	time_measure_test \
-	error_test 
+	unionfind_test \
+	xy_test
 
 
@@ -20,4 +27,5 @@
 error_test_SOURCES = error_test.cc
 graph_test_SOURCES = graph_test.cc
+kruskal_test_SOURCES = kruskal_test.cc
 mincostflows_test_SOURCES = mincostflows_test.cc
 minlengthpaths_test_SOURCES = minlengthpaths_test.cc
Index: src/test/kruskal_test.cc
===================================================================
--- src/test/kruskal_test.cc	(revision 810)
+++ src/test/kruskal_test.cc	(revision 810)
@@ -0,0 +1,94 @@
+#include <iostream>
+#include <vector>
+
+#include "test_tools.h"
+#include <hugo/maps.h>
+#include <hugo/kruskal.h>
+#include <hugo/list_graph.h>
+#include <hugo/skeletons/maps.h>
+#include <hugo/skeletons/graph.h>
+
+
+using namespace std;
+using namespace hugo;
+
+void checkCompileKruskal()
+{
+  skeleton::WriteMap<skeleton::StaticGraphSkeleton::Edge,bool> w;
+
+  kruskalEdgeMap(skeleton::StaticGraphSkeleton(),
+		 skeleton::ReadMap<skeleton::StaticGraphSkeleton::Edge,int>(),
+		 w);
+}
+
+int main() {
+
+  typedef ListGraph::Node Node;
+  typedef ListGraph::Edge Edge;
+  typedef ListGraph::NodeIt NodeIt;
+  typedef ListGraph::EdgeIt EdgeIt;
+
+  ListGraph G;
+
+  Node s=G.addNode();
+  Node v1=G.addNode();
+  Node v2=G.addNode();
+  Node v3=G.addNode();
+  Node v4=G.addNode();
+  Node t=G.addNode();
+  
+  Edge e1 = G.addEdge(s, v1);
+  Edge e2 = G.addEdge(s, v2);
+  Edge e3 = G.addEdge(v1, v2);
+  Edge e4 = G.addEdge(v2, v1);
+  Edge e5 = G.addEdge(v1, v3);
+  Edge e6 = G.addEdge(v3, v2);
+  Edge e7 = G.addEdge(v2, v4);
+  Edge e8 = G.addEdge(v4, v3);
+  Edge e9 = G.addEdge(v3, t);
+  Edge e10 = G.addEdge(v4, t);
+
+  typedef ListGraph::EdgeMap<int> ECostMap;
+  typedef ListGraph::EdgeMap<bool> EBoolMap;
+
+  ECostMap edge_cost_map(G, 2);
+  EBoolMap tree_map(G);
+  
+
+  //Test with const map.
+  check(kruskalEdgeMap(G, ConstMap<ListGraph::Edge,int>(2), tree_map)==10,
+	"Total cost should be 10");
+  //Test with a edge map (filled with uniform costs).
+  check(kruskalEdgeMap(G, edge_cost_map, tree_map)==10,
+	"Total cost should be 10");
+
+  edge_cost_map.set(e1, -10);
+  edge_cost_map.set(e2, -9);
+  edge_cost_map.set(e3, -8);
+  edge_cost_map.set(e4, -7);
+  edge_cost_map.set(e5, -6);
+  edge_cost_map.set(e6, -5);
+  edge_cost_map.set(e7, -4);
+  edge_cost_map.set(e8, -3);
+  edge_cost_map.set(e9, -2);
+  edge_cost_map.set(e10, -1);
+
+  vector<Edge> tree_edge_vec;
+
+  //Test with a edge map and inserter.
+  check(kruskalEdgeMap_IteratorOut(G, edge_cost_map,
+				   back_inserter(tree_edge_vec))
+	==-31,
+	"Total cost should be -31.");
+
+  check(tree_edge_vec.size()==5,"The tree should have 5 edges.");
+
+  check(tree_edge_vec[0]==e1 &&
+	tree_edge_vec[1]==e2 &&
+	tree_edge_vec[2]==e5 &&
+	tree_edge_vec[3]==e7 &&
+	tree_edge_vec[4]==e9,
+	"Wrong tree.");
+
+  return 0;
+}