test: Add test for vertices and edge count in pgraph

pgraph/pgraph_test.go

@@ -15,12 +15,14 @@
 // You should have received a copy of the GNU General Public License
 // along with this program. If not, see <http://www.gnu.org/licenses/>.
 
+//go:build !root
 // +build !root
 
 package pgraph
 
 import (
  "reflect"
+ "strconv"
  "testing"
 )
 
@@ -49,6 +51,54 @@ func TestCount1(t *testing.T) {
  }
 }
 
+func TestCountNodesAndEdges(t *testing.T) {
+
+ G := &Graph{Name: "MyG"}
+
+ if i := G.NumVertices(); i != 0 {
+ t.Errorf("should have 0 vertices instead of: %d", i)
+ }
+
+ if i := G.NumEdges(); i != 0 {
+ t.Errorf("should have 0 edges instead of: %d", i)
+ }
+
+ // populate vertices
+ var vertices [6]Vertex
+ for i := 0; i < len(vertices); i++ {
+ var name string = "v" + strconv.Itoa(i+1)
+ vertices[i] = NV(name)
+ }
+
+ // populate edges
+ var edges [5]Edge
+ for x := 0; x < len(edges); x++ {
+ var name string = "e" + strconv.Itoa(x+1)
+ edges[x] = NE(name)
+ }
+
+ // add all the vertices
+ for a := 0; a < len(vertices); a++ {
+ G.AddVertex(vertices[a])
+ }
+
+ // add edges to the vertices
+ for a := 0; a < len(vertices); a++ {
+ var b int = a + 1
+ if a <= len(vertices)-2 {
+ G.AddEdge(vertices[a], vertices[b], edges[a])
+ }
+ }
+
+ if y := G.NumVertices(); y != 6 {
+ t.Errorf("should have 6 vertices instead of: %d", y)
+ }
+
+ if w := G.NumEdges(); w != 5 {
+ t.Errorf("should have 5 edges instead of: %d", w)
+ }
+}
+
 func TestAddVertex1(t *testing.T) {
  G := &Graph{Name: "g2"}
  v1 := NV("v1")