structure: add omitnested support to IsZero and HasZero

structure.go

@@ -134,7 +134,9 @@ func IsZero(s interface{}) bool {
 	for _, field := range fields {
 		val := v.FieldByName(field.Name)
 
-		if IsStruct(val.Interface()) {
+		_, tagOpts := parseTag(field.Tag.Get(DefaultTagName))
+
+		if IsStruct(val.Interface()) && !tagOpts.Has("omitnested") {
 			ok := IsZero(val.Interface())
 			if !ok {
 				return false
@@ -171,7 +173,10 @@ func HasZero(s interface{}) bool {
 
 	for _, field := range fields {
 		val := v.FieldByName(field.Name)
-		if IsStruct(val.Interface()) {
+
+		_, tagOpts := parseTag(field.Tag.Get(DefaultTagName))
+
+		if IsStruct(val.Interface()) && !tagOpts.Has("omitnested") {
 			ok := HasZero(val.Interface())
 			if ok {
 				return true

structure_test.go

@@ -548,6 +548,34 @@ func TestIsZero(t *testing.T) {
 	}
 }
 
+func TestIsZero_OmitNested(t *testing.T) {
+	type A struct {
+		Name string
+		D    string
+	}
+	a := A{Name: "example"}
+
+	type B struct {
+		A A `structure:",omitnested"`
+		C int
+	}
+	b := &B{A: a, C: 123}
+
+	ok := IsZero(b)
+	if ok {
+		t.Error("IsZero should return false because A, B and C are initialized")
+	}
+
+	aZero := A{}
+	bZero := &B{A: aZero}
+
+	ok = IsZero(bZero)
+	if !ok {
+		t.Error("IsZero should return true because neither A nor B is initialized")
+	}
+
+}
+
 func TestIsZero_Nested(t *testing.T) {
 	type A struct {
 		Name string
@@ -647,6 +675,27 @@ func TestHasZero(t *testing.T) {
 	}
 }
 
+func TestHasZero_OmitNested(t *testing.T) {
+	type A struct {
+		Name string
+		D    string
+	}
+	a := A{Name: "example"}
+
+	type B struct {
+		A A `structure:",omitnested"`
+		C int
+	}
+	b := &B{A: a, C: 123}
+
+	// Because the Field A inside B is omitted  HasZero should return false
+	// because it will stop iterating deeper andnot going to lookup for D
+	ok := HasZero(b)
+	if ok {
+		t.Error("HasZero should return false because A and C are initialized")
+	}
+}
+
 func TestHasZero_Nested(t *testing.T) {
 	type A struct {
 		Name string

tags.go

@@ -5,7 +5,7 @@ import "strings"
 // tagOptions contains a slice of tag options
 type tagOptions []string
 
-// Has returns true if the given opt is available inside the slice.
+// Has returns true if the given optiton is available in tagOptions
 func (t tagOptions) Has(opt string) bool {
 	for _, tagOpt := range t {
 		if tagOpt == opt {