diff --git a/node/expr/n_class_const_fetch.go b/node/expr/n_class_const_fetch.go
index 2dac6f8..bbf1c0b 100644
--- a/node/expr/n_class_const_fetch.go
+++ b/node/expr/n_class_const_fetch.go
@@ -31,15 +31,15 @@ func (n *ClassConstFetch) Walk(v walker.Visitor) {
 		return
 	}
 
-	if n.ConstantName != nil {
-		vv := v.GetChildrenVisitor("ConstantName")
-		n.ConstantName.Walk(vv)
-	}
-
 	if n.Class != nil {
 		vv := v.GetChildrenVisitor("Class")
 		n.Class.Walk(vv)
 	}
 
+	if n.ConstantName != nil {
+		vv := v.GetChildrenVisitor("ConstantName")
+		n.ConstantName.Walk(vv)
+	}
+
 	v.LeaveNode(n)
 }
diff --git a/node/expr/n_closure_use.go b/node/expr/n_closure_use.go
index 2ba7191..af33a22 100644
--- a/node/expr/n_closure_use.go
+++ b/node/expr/n_closure_use.go
@@ -5,22 +5,22 @@ import (
 	"github.com/z7zmey/php-parser/walker"
 )
 
-// ClusureUse node
-type ClusureUse struct {
+// ClosureUse node
+type ClosureUse struct {
 	ByRef    bool
 	Variable node.Node
 }
 
-// NewClusureUse node constuctor
-func NewClusureUse(Variable node.Node, ByRef bool) *ClusureUse {
-	return &ClusureUse{
+// NewClosureUse node constuctor
+func NewClosureUse(Variable node.Node, ByRef bool) *ClosureUse {
+	return &ClosureUse{
 		ByRef,
 		Variable,
 	}
 }
 
 // Attributes returns node attributes as map
-func (n *ClusureUse) Attributes() map[string]interface{} {
+func (n *ClosureUse) Attributes() map[string]interface{} {
 	return map[string]interface{}{
 		"ByRef": n.ByRef,
 	}
@@ -28,7 +28,7 @@ func (n *ClusureUse) Attributes() map[string]interface{} {
 
 // Walk traverses nodes
 // Walk is invoked recursively until v.EnterNode returns true
-func (n *ClusureUse) Walk(v walker.Visitor) {
+func (n *ClosureUse) Walk(v walker.Visitor) {
 	if v.EnterNode(n) == false {
 		return
 	}
diff --git a/node/expr/t_visitor_test.go b/node/expr/t_visitor_test.go
new file mode 100644
index 0000000..7be9a11
--- /dev/null
+++ b/node/expr/t_visitor_test.go
@@ -0,0 +1,406 @@
+package expr_test
+
+import (
+	"reflect"
+	"testing"
+
+	"github.com/z7zmey/php-parser/node/stmt"
+
+	"github.com/z7zmey/php-parser/node/name"
+
+	"github.com/z7zmey/php-parser/node/scalar"
+
+	"github.com/kylelemons/godebug/pretty"
+
+	"github.com/z7zmey/php-parser/node"
+	"github.com/z7zmey/php-parser/node/expr"
+	"github.com/z7zmey/php-parser/walker"
+)
+
+var nodesToTest = []struct {
+	node                node.Node // node
+	expectedVisitedKeys []string  // visited keys
+	expectedAttributes  map[string]interface{}
+}{
+	{
+		&expr.ArrayDimFetch{
+			Variable: &expr.Variable{VarName: &node.Identifier{Value: "$a"}},
+			Dim:      &scalar.Lnumber{Value: "1"},
+		},
+		[]string{"Variable", "Dim"},
+		map[string]interface{}{},
+	},
+	{
+		&expr.ArrayItem{
+			ByRef: false,
+			Key:   &scalar.String{Value: "key"},
+			Val:   &scalar.Lnumber{Value: "1"},
+		},
+		[]string{"Key", "Val"},
+		map[string]interface{}{"ByRef": false},
+	},
+	{
+		&expr.Array{
+			Items: []node.Node{
+				&expr.ArrayItem{
+					ByRef: false,
+					Key:   &scalar.String{Value: "key"},
+					Val:   &scalar.Lnumber{Value: "1"},
+				},
+			},
+		},
+		[]string{"Items"},
+		map[string]interface{}{},
+	},
+	{
+		&expr.BitwiseNot{
+			Expr: &expr.Variable{VarName: &node.Identifier{Value: "$a"}},
+		},
+		[]string{"Expr"},
+		map[string]interface{}{},
+	},
+	{
+		&expr.BooleanNot{
+			Expr: &expr.Variable{VarName: &node.Identifier{Value: "$a"}},
+		},
+		[]string{"Expr"},
+		map[string]interface{}{},
+	},
+	{
+		&expr.ClassConstFetch{
+			Class:        &expr.Variable{VarName: &node.Identifier{Value: "$a"}},
+			ConstantName: &node.Identifier{Value: "foo"},
+		},
+		[]string{"Class", "ConstantName"},
+		map[string]interface{}{},
+	},
+	{
+		&expr.Clone{
+			Expr: &expr.Variable{VarName: &node.Identifier{Value: "$a"}},
+		},
+		[]string{"Expr"},
+		map[string]interface{}{},
+	},
+	{
+		&expr.ClosureUse{
+			ByRef:    false,
+			Variable: &expr.Variable{VarName: &node.Identifier{Value: "$a"}},
+		},
+		[]string{"Variable"},
+		map[string]interface{}{"ByRef": false},
+	},
+	{
+		&expr.Closure{
+			ReturnsRef:    true,
+			Static:        false,
+			PhpDocComment: "",
+			Params:        []node.Node{&node.Parameter{}},
+			Uses:          []node.Node{&expr.ClosureUse{}},
+			ReturnType:    &name.Name{},
+			Stmts:         []node.Node{&stmt.Nop{}},
+		},
+		[]string{"Params", "Uses", "ReturnType", "Stmts"},
+		map[string]interface{}{"ReturnsRef": true, "Static": false, "PhpDocComment": ""},
+	},
+	{
+		&expr.ConstFetch{
+			Constant: &node.Identifier{Value: "foo"},
+		},
+		[]string{"Constant"},
+		map[string]interface{}{},
+	},
+	{
+		&expr.Empty{
+			Expr: &expr.Variable{VarName: &node.Identifier{Value: "$a"}},
+		},
+		[]string{"Expr"},
+		map[string]interface{}{},
+	},
+	{
+		&expr.ErrorSuppress{
+			Expr: &expr.Variable{VarName: &node.Identifier{Value: "$a"}},
+		},
+		[]string{"Expr"},
+		map[string]interface{}{},
+	},
+	{
+		&expr.Eval{
+			Expr: &expr.Variable{VarName: &node.Identifier{Value: "$a"}},
+		},
+		[]string{"Expr"},
+		map[string]interface{}{},
+	},
+	{
+		&expr.Exit{
+			Expr:  &expr.Variable{VarName: &node.Identifier{Value: "$a"}},
+			IsDie: false,
+		},
+		[]string{"Expr"},
+		map[string]interface{}{"IsDie": false},
+	},
+	{
+		&expr.FunctionCall{
+			Function:  &expr.Variable{VarName: &node.Identifier{Value: "$a"}},
+			Arguments: []node.Node{&node.Argument{}},
+		},
+		[]string{"Function", "Arguments"},
+		map[string]interface{}{},
+	},
+	{
+		&expr.IncludeOnce{
+			Expr: &expr.Variable{VarName: &node.Identifier{Value: "$a"}},
+		},
+		[]string{"Expr"},
+		map[string]interface{}{},
+	},
+	{
+		&expr.Include{
+			Expr: &expr.Variable{VarName: &node.Identifier{Value: "$a"}},
+		},
+		[]string{"Expr"},
+		map[string]interface{}{},
+	},
+	{
+		&expr.InstanceOf{
+			Expr:  &expr.Variable{VarName: &node.Identifier{Value: "$a"}},
+			Class: &name.Name{},
+		},
+		[]string{"Expr", "Class"},
+		map[string]interface{}{},
+	},
+	{
+		&expr.Isset{
+			Variables: []node.Node{
+				&expr.Variable{VarName: &node.Identifier{Value: "$a"}},
+			},
+		},
+		[]string{"Variables"},
+		map[string]interface{}{},
+	},
+	{
+		&expr.List{
+			Items: []node.Node{
+				&expr.ArrayItem{},
+			},
+		},
+		[]string{"Items"},
+		map[string]interface{}{},
+	},
+	{
+		&expr.MethodCall{
+			Variable:  &expr.Variable{VarName: &node.Identifier{Value: "$a"}},
+			Method:    &node.Identifier{Value: "foo"},
+			Arguments: []node.Node{&node.Argument{}},
+		},
+		[]string{"Variable", "Method", "Arguments"},
+		map[string]interface{}{},
+	},
+	{
+		&expr.New{
+			Class:     &name.Name{},
+			Arguments: []node.Node{&node.Argument{}},
+		},
+		[]string{"Class", "Arguments"},
+		map[string]interface{}{},
+	},
+	{
+		&expr.PostDec{
+			Variable: &expr.Variable{VarName: &node.Identifier{Value: "$a"}},
+		},
+		[]string{"Variable"},
+		map[string]interface{}{},
+	},
+	{
+		&expr.PostInc{
+			Variable: &expr.Variable{VarName: &node.Identifier{Value: "$a"}},
+		},
+		[]string{"Variable"},
+		map[string]interface{}{},
+	},
+	{
+		&expr.PreDec{
+			Variable: &expr.Variable{VarName: &node.Identifier{Value: "$a"}},
+		},
+		[]string{"Variable"},
+		map[string]interface{}{},
+	},
+	{
+		&expr.PreInc{
+			Variable: &expr.Variable{VarName: &node.Identifier{Value: "$a"}},
+		},
+		[]string{"Variable"},
+		map[string]interface{}{},
+	},
+	{
+		&expr.Print{
+			Expr: &expr.Variable{VarName: &node.Identifier{Value: "$a"}},
+		},
+		[]string{"Expr"},
+		map[string]interface{}{},
+	},
+	{
+		&expr.PropertyFetch{
+			Variable: &expr.Variable{VarName: &node.Identifier{Value: "$a"}},
+			Property: &node.Identifier{Value: "foo"},
+		},
+		[]string{"Variable", "Property"},
+		map[string]interface{}{},
+	},
+	{
+		&expr.RequireOnce{
+			Expr: &expr.Variable{VarName: &node.Identifier{Value: "$a"}},
+		},
+		[]string{"Expr"},
+		map[string]interface{}{},
+	},
+	{
+		&expr.Require{
+			Expr: &expr.Variable{VarName: &node.Identifier{Value: "$a"}},
+		},
+		[]string{"Expr"},
+		map[string]interface{}{},
+	},
+	{
+		&expr.ShellExec{
+			Parts: []node.Node{
+				&scalar.EncapsedStringPart{},
+			},
+		},
+		[]string{"Parts"},
+		map[string]interface{}{},
+	},
+	{
+		&expr.ShortArray{
+			Items: []node.Node{
+				&expr.ArrayItem{},
+			},
+		},
+		[]string{"Items"},
+		map[string]interface{}{},
+	},
+	{
+		&expr.ShortList{
+			Items: []node.Node{
+				&expr.ArrayItem{},
+			},
+		},
+		[]string{"Items"},
+		map[string]interface{}{},
+	},
+	{
+		&expr.StaticCall{
+			Class:     &name.Name{},
+			Call:      &node.Identifier{Value: "foo"},
+			Arguments: []node.Node{&node.Argument{}},
+		},
+		[]string{"Class", "Call", "Arguments"},
+		map[string]interface{}{},
+	},
+	{
+		&expr.StaticPropertyFetch{
+			Class:    &name.Name{},
+			Property: &node.Identifier{Value: "foo"},
+		},
+		[]string{"Class", "Property"},
+		map[string]interface{}{},
+	},
+	{
+		&expr.Ternary{
+			Condition: &expr.Variable{VarName: &node.Identifier{Value: "$a"}},
+			IfTrue:    &expr.Variable{VarName: &node.Identifier{Value: "$b"}},
+			IfFalse:   &expr.Variable{VarName: &node.Identifier{Value: "$c"}},
+		},
+		[]string{"Condition", "IfTrue", "IfFalse"},
+		map[string]interface{}{},
+	},
+	{
+		&expr.UnaryMinus{
+			Expr: &expr.Variable{VarName: &node.Identifier{Value: "$a"}},
+		},
+		[]string{"Expr"},
+		map[string]interface{}{},
+	},
+	{
+		&expr.UnaryPlus{
+			Expr: &expr.Variable{VarName: &node.Identifier{Value: "$a"}},
+		},
+		[]string{"Expr"},
+		map[string]interface{}{},
+	},
+	{
+		&expr.Variable{VarName: &node.Identifier{Value: "$a"}},
+		[]string{"VarName"},
+		map[string]interface{}{},
+	},
+	{
+		&expr.YieldFrom{
+			Expr: &expr.Variable{VarName: &node.Identifier{Value: "$a"}},
+		},
+		[]string{"Expr"},
+		map[string]interface{}{},
+	},
+	{
+		&expr.Yield{
+			Key:   &expr.Variable{VarName: &node.Identifier{Value: "$a"}},
+			Value: &expr.Variable{VarName: &node.Identifier{Value: "$b"}},
+		},
+		[]string{"Key", "Value"},
+		map[string]interface{}{},
+	},
+}
+
+type visitorMock struct {
+	visitChildren bool
+	visitedKeys   []string
+}
+
+func (v *visitorMock) EnterNode(n walker.Walker) bool { return v.visitChildren }
+func (v *visitorMock) GetChildrenVisitor(key string) walker.Visitor {
+	v.visitedKeys = append(v.visitedKeys, key)
+	return &visitorMock{v.visitChildren, nil}
+}
+func (v *visitorMock) LeaveNode(n walker.Walker) {}
+
+func TestVisitorDisableChildren(t *testing.T) {
+	for _, tt := range nodesToTest {
+		v := &visitorMock{false, nil}
+		tt.node.Walk(v)
+
+		expected := []string{}
+		actual := v.visitedKeys
+
+		diff := pretty.Compare(expected, actual)
+		if diff != "" {
+			t.Errorf("%s diff: (-expected +actual)\n%s", reflect.TypeOf(tt.node), diff)
+		}
+	}
+}
+
+func TestVisitor(t *testing.T) {
+	for _, tt := range nodesToTest {
+		v := &visitorMock{true, nil}
+		tt.node.Walk(v)
+
+		expected := tt.expectedVisitedKeys
+		actual := v.visitedKeys
+
+		diff := pretty.Compare(expected, actual)
+		if diff != "" {
+			t.Errorf("%s diff: (-expected +actual)\n%s", reflect.TypeOf(tt.node), diff)
+		}
+	}
+}
+
+// test Attributes()
+
+func TestNameAttributes(t *testing.T) {
+	for _, tt := range nodesToTest {
+		expected := tt.expectedAttributes
+		actual := tt.node.Attributes()
+
+		diff := pretty.Compare(expected, actual)
+		if diff != "" {
+			t.Errorf("%s diff: (-expected +actual)\n%s", reflect.TypeOf(tt.node), diff)
+		}
+	}
+}
diff --git a/php5/php5.go b/php5/php5.go
index 9a1478a..a6b8466 100644
--- a/php5/php5.go
+++ b/php5/php5.go
@@ -4935,7 +4935,7 @@ yydefault:
 			positions.AddPosition(variable, positionBuilder.NewTokenPosition(yyDollar[3].token))
 			comments.AddComments(variable, yyDollar[3].token.Comments())
 
-			use := expr.NewClusureUse(variable, false)
+			use := expr.NewClosureUse(variable, false)
 			positions.AddPosition(use, positionBuilder.NewTokenPosition(yyDollar[3].token))
 			comments.AddComments(use, yyDollar[3].token.Comments())
 
@@ -4953,7 +4953,7 @@ yydefault:
 			positions.AddPosition(variable, positionBuilder.NewTokenPosition(yyDollar[4].token))
 			comments.AddComments(variable, yyDollar[3].token.Comments())
 
-			use := expr.NewClusureUse(variable, true)
+			use := expr.NewClosureUse(variable, true)
 			positions.AddPosition(use, positionBuilder.NewTokensPosition(yyDollar[3].token, yyDollar[4].token))
 			comments.AddComments(use, yyDollar[3].token.Comments())
 
@@ -4971,7 +4971,7 @@ yydefault:
 			positions.AddPosition(variable, positionBuilder.NewTokenPosition(yyDollar[1].token))
 			comments.AddComments(variable, yyDollar[1].token.Comments())
 
-			use := expr.NewClusureUse(variable, false)
+			use := expr.NewClosureUse(variable, false)
 			positions.AddPosition(use, positionBuilder.NewTokenPosition(yyDollar[1].token))
 			comments.AddComments(use, yyDollar[1].token.Comments())
 
@@ -4989,7 +4989,7 @@ yydefault:
 			positions.AddPosition(variable, positionBuilder.NewTokenPosition(yyDollar[2].token))
 			comments.AddComments(variable, yyDollar[1].token.Comments())
 
-			use := expr.NewClusureUse(variable, true)
+			use := expr.NewClosureUse(variable, true)
 			positions.AddPosition(use, positionBuilder.NewTokensPosition(yyDollar[1].token, yyDollar[2].token))
 			comments.AddComments(use, yyDollar[1].token.Comments())
 
diff --git a/php5/php5.y b/php5/php5.y
index b8623ca..4c994c3 100644
--- a/php5/php5.y
+++ b/php5/php5.y
@@ -2369,7 +2369,7 @@ lexical_var_list:
                 positions.AddPosition(variable, positionBuilder.NewTokenPosition($3))
                 comments.AddComments(variable, $3.Comments())
                 
-                use := expr.NewClusureUse(variable, false)
+                use := expr.NewClosureUse(variable, false)
                 positions.AddPosition(use, positionBuilder.NewTokenPosition($3))
                 comments.AddComments(use, $3.Comments())
                 
@@ -2385,7 +2385,7 @@ lexical_var_list:
                 positions.AddPosition(variable, positionBuilder.NewTokenPosition($4))
                 comments.AddComments(variable, $3.Comments())
 
-                use := expr.NewClusureUse(variable, true)
+                use := expr.NewClosureUse(variable, true)
                 positions.AddPosition(use, positionBuilder.NewTokensPosition($3, $4))
                 comments.AddComments(use, $3.Comments())
 
@@ -2401,7 +2401,7 @@ lexical_var_list:
                 positions.AddPosition(variable, positionBuilder.NewTokenPosition($1))
                 comments.AddComments(variable, $1.Comments())
                 
-                use := expr.NewClusureUse(variable, false)
+                use := expr.NewClosureUse(variable, false)
                 positions.AddPosition(use, positionBuilder.NewTokenPosition($1))
                 comments.AddComments(use, $1.Comments())
                 
@@ -2417,7 +2417,7 @@ lexical_var_list:
                 positions.AddPosition(variable, positionBuilder.NewTokenPosition($2))
                 comments.AddComments(variable, $1.Comments())
 
-                use := expr.NewClusureUse(variable, true)
+                use := expr.NewClosureUse(variable, true)
                 positions.AddPosition(use, positionBuilder.NewTokensPosition($1, $2))
                 comments.AddComments(use, $1.Comments())
 
diff --git a/php7/php7.go b/php7/php7.go
index 5e0994e..d0eace0 100644
--- a/php7/php7.go
+++ b/php7/php7.go
@@ -4830,7 +4830,7 @@ yydefault:
 			positions.AddPosition(identifier, positionBuilder.NewTokenPosition(yyDollar[1].token))
 			variable := expr.NewVariable(identifier)
 			positions.AddPosition(variable, positionBuilder.NewTokenPosition(yyDollar[1].token))
-			yyVAL.node = expr.NewClusureUse(variable, false)
+			yyVAL.node = expr.NewClosureUse(variable, false)
 			positions.AddPosition(yyVAL.node, positionBuilder.NewTokenPosition(yyDollar[1].token))
 
 			comments.AddComments(identifier, yyDollar[1].token.Comments())
@@ -4845,7 +4845,7 @@ yydefault:
 			positions.AddPosition(identifier, positionBuilder.NewTokenPosition(yyDollar[2].token))
 			variable := expr.NewVariable(identifier)
 			positions.AddPosition(variable, positionBuilder.NewTokenPosition(yyDollar[2].token))
-			yyVAL.node = expr.NewClusureUse(variable, true)
+			yyVAL.node = expr.NewClosureUse(variable, true)
 			positions.AddPosition(yyVAL.node, positionBuilder.NewTokensPosition(yyDollar[1].token, yyDollar[2].token))
 
 			comments.AddComments(identifier, yyDollar[2].token.Comments())
diff --git a/php7/php7.y b/php7/php7.y
index 813a07c..807f917 100644
--- a/php7/php7.y
+++ b/php7/php7.y
@@ -1933,7 +1933,7 @@ lexical_var:
             positions.AddPosition(identifier, positionBuilder.NewTokenPosition($1))
             variable := expr.NewVariable(identifier)
             positions.AddPosition(variable, positionBuilder.NewTokenPosition($1))
-            $$ = expr.NewClusureUse(variable, false)
+            $$ = expr.NewClosureUse(variable, false)
             positions.AddPosition($$, positionBuilder.NewTokenPosition($1))
 
             comments.AddComments(identifier, $1.Comments())
@@ -1946,7 +1946,7 @@ lexical_var:
             positions.AddPosition(identifier, positionBuilder.NewTokenPosition($2))
             variable := expr.NewVariable(identifier)
             positions.AddPosition(variable, positionBuilder.NewTokenPosition($2))
-            $$ = expr.NewClusureUse(variable, true)
+            $$ = expr.NewClosureUse(variable, true)
             positions.AddPosition($$, positionBuilder.NewTokensPosition($1, $2))
 
             comments.AddComments(identifier, $2.Comments())