feat: add MustSet function and its test

defaults.go

@@ -42,6 +42,14 @@ func Set(ptr interface{}) error {
 	return nil
 }
 
+// MustSet function is a wrapper of Set function
+// It will call Set and panic if err not equals nil.
+func MustSet(ptr interface{}) {
+	if err := Set(ptr); err != nil {
+		panic(err)
+	}
+}
+
 func setField(field reflect.Value, defaultVal string) error {
 	if !field.CanSet() {
 		return nil

defaults_test.go

@@ -142,6 +142,24 @@ type Emmbeded struct {
 	Int int `default:"1"`
 }
 
+func TestMustSet(t *testing.T) {
+	sample := &Sample{
+		NonInitialString:            "string",
+		NonInitialSlice:             []int{1, 2, 3},
+		NonInitialStruct:            Struct{Foo: 123},
+		NonInitialStructPtr:         &Struct{Foo: 123},
+		DeepSliceOfStructsWithNoTag: [][][]Struct{{{{Foo: 123}}}},
+	}
+
+	MustSet(sample)
+	go func() {
+		if err := recover(); err != nil {
+			t.Fatalf("it should not panic error: %v", err)
+		}
+	}()
+	t.Log("it works.")
+}
+
 func TestInit(t *testing.T) {
 	sample := &Sample{
 		NonInitialString:            "string",