fix: must provide ptr for call FromStruct

gflag.go

@@ -116,13 +116,18 @@ func NewFlags(nameWithDesc ...string) *Flags {
 }
 
 var flagValueType = reflect.TypeOf(new(flag.Value)).Elem()
-var errNotAnStruct = errors.New("must input an struct")
+var errNotPtrValue = errors.New("must provide an ptr value")
+var errNotAnStruct = errors.New("must provide an struct ptr")
 var errTagRuleType = errors.New("invalid tag rule type on struct")
 
 // FromStruct from struct tag binding options
-func (fs *Flags) FromStruct(s interface{}) error {
-	v := reflect.ValueOf(s)
-	if v.Kind() == reflect.Ptr && !v.IsNil() {
+func (fs *Flags) FromStruct(ptr interface{}) error {
+	v := reflect.ValueOf(ptr)
+	if v.Kind() != reflect.Ptr {
+		return errNotPtrValue
+	}
+
+	if !v.IsNil() {
 		v = v.Elem()
 	}
 
@@ -240,6 +245,12 @@ func (fs *Flags) SetOptions(opt *FlagsOption) {
 	fs.opt = opt
 }
 
+// UseSimpleRule for the parse tag value rule string. see TagRuleSimple
+func (fs *Flags) UseSimpleRule() *Flags {
+	fs.opt.TagRuleType = TagRuleSimple
+	return fs
+}
+
 // WithOptions for the object.
 func (fs *Flags) WithOptions(fns func(opt *FlagsOption)) *Flags {
 	fns(fs.opt)

gflag_test.go

@@ -382,6 +382,11 @@ func TestFlags_FromStruct_simple(t *testing.T) {
 
 	assert.Equal(t, 13, opt.Int)
 	assert.Equal(t, "xyz", opt.Str)
+
+	// not use ptr
+	opts1 := userOpts0{}
+	err = fs.FromStruct(opts1)
+	assert.Error(t, err)
 }
 
 func TestFlags_FromStruct_ptrField(t *testing.T) {
@@ -417,6 +422,25 @@ func TestFlags_FromStruct_ptrField(t *testing.T) {
 	fs.PrintHelpPanel()
 }
 
+func TestFlags_FromStruct_noNameStruct(t *testing.T) {
+	logOpts := struct {
+		Abbrev    bool `flag:"Only display the abbrev commit ID"`
+		NoColor   bool	`flag:"Dont use color render git output"`
+		MaxCommit int	`flag:"Max display how many commits;;15"`
+		Logfile   string      `flag:"export changelog message to file"`
+		Exclude   gcli.String `flag:"exclude contains given sub-string. multi by comma split."`
+	}{}
+
+	fs := gcli.NewFlags("test")
+	fs.UseSimpleRule()
+	// err := fs.FromStruct(logOpts)
+	err := fs.FromStruct(&logOpts)
+
+	assert.NoError(t, err)
+	assert.True(t, fs.HasFlag("abbrev"))
+	assert.True(t, fs.HasFlagMeta("abbrev"))
+}
+
 func TestFlags_FromStruct(t *testing.T) {
 	type userOpts struct {
 		Int  int    `flag:"name=int0;shorts=i;required=true;desc=int option message"`