Golang Iterator.Type方法代码示例

func (qs *QuadStore) OptimizeIterator(it graph.Iterator) (graph.Iterator, bool) {
	switch it.Type() {
	case graph.LinksTo:
		return qs.optimizeLinksTo(it.(*iterator.LinksTo))

	}
	return it, false
}

func TestIterator(t *testing.T) {
	tmpDir, err := ioutil.TempDir(os.TempDir(), "cayley_test")
	if err != nil {
		t.Fatalf("Could not create working directory: %v", err)
	}
	defer os.RemoveAll(tmpDir)
	t.Log(tmpDir)

	err = createNewLevelDB(tmpDir, nil)
	if err != nil {
		t.Fatal("Failed to create LevelDB database.")
	}

	qs, err := newQuadStore(tmpDir, nil)
	if qs == nil || err != nil {
		t.Error("Failed to create leveldb QuadStore.")
	}

	w, _ := writer.NewSingleReplication(qs, nil)
	w.AddQuadSet(makeQuadSet())
	var it graph.Iterator

	it = qs.NodesAllIterator()
	if it == nil {
		t.Fatal("Got nil iterator.")
	}

	size, exact := it.Size()
	if size <= 0 || size >= 20 {
		t.Errorf("Unexpected size, got:%d expect:(0, 20)", size)
	}
	if exact {
		t.Errorf("Got unexpected exact result.")
	}
	if typ := it.Type(); typ != graph.All {
		t.Errorf("Unexpected iterator type, got:%v expect:%v", typ, graph.All)
	}
	optIt, changed := it.Optimize()
	if changed || optIt != it {
		t.Errorf("Optimize unexpectedly changed iterator.")
	}

	expect := []string{
		"A",
		"B",
		"C",
		"D",
		"E",
		"F",
		"G",
		"follows",
		"status",
		"cool",
		"status_graph",
	}
	sort.Strings(expect)
	for i := 0; i < 2; i++ {
		got := iteratedNames(qs, it)
		sort.Strings(got)
		if !reflect.DeepEqual(got, expect) {
			t.Errorf("Unexpected iterated result on repeat %d, got:%v expect:%v", i, got, expect)
		}
		it.Reset()
	}

	for _, pq := range expect {
		if !it.Contains(qs.ValueOf(pq)) {
			t.Errorf("Failed to find and check %q correctly", pq)
		}
	}
	// FIXME(kortschak) Why does this fail?
	/*
		for _, pq := range []string{"baller"} {
			if it.Contains(qs.ValueOf(pq)) {
				t.Errorf("Failed to check %q correctly", pq)
			}
		}
	*/
	it.Reset()

	it = qs.QuadsAllIterator()
	graph.Next(it)
	q := qs.Quad(it.Result())
	set := makeQuadSet()
	var ok bool
	for _, t := range set {
		if t.String() == q.String() {
			ok = true
			break
		}
	}
	if !ok {
		t.Errorf("Failed to find %q during iteration, got:%q", q, set)
	}

	qs.Close()
}

func (s *queryShape) MakeNode(it graph.Iterator) *Node {
	n := Node{ID: s.nodeID}
	for _, tag := range it.Tagger().Tags() {
		n.Tags = append(n.Tags, tag)
	}
	for k := range it.Tagger().Fixed() {
		n.Tags = append(n.Tags, k)
	}

	switch it.Type() {
	case graph.And:
		for _, sub := range it.SubIterators() {
			s.nodeID++
			newNode := s.MakeNode(sub)
			if sub.Type() != graph.Or {
				s.StealNode(&n, newNode)
			} else {
				s.AddNode(newNode)
				s.AddLink(&Link{n.ID, newNode.ID, 0, 0})
			}
		}
	case graph.Fixed:
		n.IsFixed = true
		for graph.Next(it) {
			n.Values = append(n.Values, s.qs.NameOf(it.Result()))
		}
	case graph.HasA:
		hasa := it.(*HasA)
		s.PushHasa(n.ID, hasa.dir)
		s.nodeID++
		newNode := s.MakeNode(hasa.primaryIt)
		s.AddNode(newNode)
		s.RemoveHasa()
	case graph.Or:
		for _, sub := range it.SubIterators() {
			s.nodeID++
			newNode := s.MakeNode(sub)
			if sub.Type() == graph.Or {
				s.StealNode(&n, newNode)
			} else {
				s.AddNode(newNode)
				s.AddLink(&Link{n.ID, newNode.ID, 0, 0})
			}
		}
	case graph.LinksTo:
		n.IsLinkNode = true
		lto := it.(*LinksTo)
		s.nodeID++
		newNode := s.MakeNode(lto.primaryIt)
		hasaID, hasaDir := s.LastHasa()
		if (hasaDir == quad.Subject && lto.dir == quad.Object) ||
			(hasaDir == quad.Object && lto.dir == quad.Subject) {
			s.AddNode(newNode)
			if hasaDir == quad.Subject {
				s.AddLink(&Link{hasaID, newNode.ID, 0, n.ID})
			} else {
				s.AddLink(&Link{newNode.ID, hasaID, 0, n.ID})
			}
		} else if lto.primaryIt.Type() == graph.Fixed {
			s.StealNode(&n, newNode)
		} else {
			s.AddNode(newNode)
		}
	case graph.Optional:
		// Unsupported, for the moment
		fallthrough
	case graph.All:
	}
	return &n
}