Add test suite for dfs.Search

also make travis run recursively with gocheck

.travis.yml

@@ -5,3 +5,4 @@ go:
 install:
   - go get -t launchpad.net/gocheck
   - go get github.com/fatih/set
+script: go test -v ./... -gocheck.v

dfs/dfs.go

@@ -32,14 +32,14 @@ func Search(g gogl.Graph, target gogl.Vertex, start gogl.Vertex) (path []gogl.Ve
 	w := walker{
 		vis: visitor,
 		g:   g,
-		// TODO is there ANY way to do this more efficiently without mutating/coloring the vertex objects directly? this is horribly slow
+		// TODO is there ANY way to do this more efficiently without mutating/coloring the vertex objects directly? this means lots of hashtable lookups
 		colors: make(map[gogl.Vertex]uint),
 		target: target,
 	}
 
 	w.dfsearch(start)
 
-	return path, nil
+	return visitor.getPath(), nil
 }
 
 // Performs a depth-first search on the provided graph for the given vertex, using the vertices
@@ -220,9 +220,12 @@ func (sv *searchVisitor) OnFinishVertex(vertex gogl.Vertex) {
 	sv.stack.pop()
 }
 
-func (sv *searchVisitor) getPath()[] gogl.Vertex {
+func (sv *searchVisitor) getPath() []gogl.Vertex {
 	path := make([]gogl.Vertex, 0, sv.stack.length())
-	for vertex := sv.stack.pop; vertex != nil; vertex = sv.stack.pop {
+
+	stacklen := sv.stack.length()
+	for i := 0; i < stacklen; i++ {
+		vertex := sv.stack.pop()
 		path = append(path, vertex)
 	}
 
@@ -327,14 +330,14 @@ func (w *walker) dfsearch(v gogl.Vertex) {
 	if color == grey {
 		w.vis.OnBackEdge(v)
 	} else if color == white {
-		w.visiting[v] = struct{}{}
+		w.colors[v] = grey
 		w.vis.OnStartVertex(v)
 
 		w.g.EachAdjacent(v, func(to gogl.Vertex) {
 			// no more new visits if complete
 			if !w.complete {
 				w.vis.OnExamineEdge(gogl.BaseEdge{v, to})
-				w.dfsearch(v)
+				w.dfsearch(to)
 			}
 		})
 		// escape hatch
@@ -343,7 +346,7 @@ func (w *walker) dfsearch(v gogl.Vertex) {
 		}
 
 		w.vis.OnFinishVertex(v)
-		w.visited[v] = struct{}{}
+		w.colors[v] = black
 	}
 }
 

dfs/dfs_test.go

@@ -1,17 +1,37 @@
 package dfs
 
 import (
+	"fmt"
 	"testing"
 
 	"github.com/sdboyer/gogl"
+	. "launchpad.net/gocheck"
 )
 
+// Hook gocheck into the go test runner
+func Test(t *testing.T) { TestingT(t) }
+
 var dfEdgeSet = []gogl.Edge{
 	&gogl.BaseEdge{"foo", "bar"},
 	&gogl.BaseEdge{"bar", "baz"},
 	&gogl.BaseEdge{"baz", "qux"},
 }
 
+type DepthFirstSearchSuite struct {
+}
+
+var _ = Suite(&DepthFirstSearchSuite{})
+
+// Basic test of outermost search functionality.
+func (s *DepthFirstSearchSuite) TestSearch(c *C) {
+	g := gogl.NewDirected()
+	g.AddEdges(dfEdgeSet...)
+
+	path, err := Search(g, "qux", "bar")
+	c.Assert(fmt.Sprint(path), Equals, fmt.Sprint([]gogl.Vertex{"qux", "baz", "bar"}))
+	c.Assert(err, IsNil)
+}
+
 func sliceEquals(a, b []gogl.Vertex) bool {
 	if len(a) != len(b) {
 		return false