add root tag in matadata of struct to specify the root command function for the object for package gcmd

os/gcmd/gcmd_command_object.go

@@ -24,8 +24,9 @@ import (
 )
 
 const (
-	tagNameDc = `dc`
-	tagNameAd = `ad`
+	tagNameDc   = `dc`
+	tagNameAd   = `ad`
+	tagNameRoot = `root`
 )
 
 var (
@@ -50,8 +51,9 @@ func NewFromObject(object interface{}) (rootCmd Command, err error) {
 	}
 	// Sub command creating.
 	var (
-		nameSet     = gset.NewStrSet()
-		subCommands []Command
+		nameSet         = gset.NewStrSet()
+		rootCommandName = gmeta.Get(object, tagNameRoot).String()
+		subCommands     []Command
 	)
 	for i := 0; i < originValueAndKind.InputValue.NumMethod(); i++ {
 		var (
@@ -69,7 +71,19 @@ func NewFromObject(object interface{}) (rootCmd Command, err error) {
 			)
 			return
 		}
-		subCommands = append(subCommands, methodCommand)
+		if rootCommandName == methodCommand.Name {
+			if rootCmd.Func == nil {
+				rootCmd.Func = methodCommand.Func
+			}
+			if rootCmd.FuncWithValue == nil {
+				rootCmd.FuncWithValue = methodCommand.FuncWithValue
+			}
+			if len(rootCmd.Options) == 0 {
+				rootCmd.Options = methodCommand.Options
+			}
+		} else {
+			subCommands = append(subCommands, methodCommand)
+		}
 	}
 	if len(subCommands) > 0 {
 		err = rootCmd.AddCommand(subCommands...)

os/gcmd/gcmd_z_unit_feature_object_test.go

@@ -96,3 +96,46 @@ func Test_Command_AddObject(t *testing.T) {
 		t.Assert(value, `{"Content":"john"}`)
 	})
 }
+
+type TestObjectForRootTag struct {
+	g.Meta `name:"root" root:"root"`
+}
+
+type TestObjectForRootTagEnvInput struct {
+	g.Meta `name:"env" usage:"root env" brief:"root env command" dc:"root env command description" ad:"root env command ad"`
+}
+type TestObjectForRootTagEnvOutput struct{}
+
+type TestObjectForRootTagTestInput struct {
+	g.Meta `name:"root"`
+	Name   string `v:"required" short:"n" orphan:"false" brief:"name for test command"`
+}
+type TestObjectForRootTagTestOutput struct {
+	Content string
+}
+
+func (TestObjectForRootTag) Env(ctx context.Context, in TestObjectForRootTagEnvInput) (out *TestObjectForRootTagEnvOutput, err error) {
+	return
+}
+
+func (TestObjectForRootTag) Root(ctx context.Context, in TestObjectForRootTagTestInput) (out *TestObjectForRootTagTestOutput, err error) {
+	out = &TestObjectForRootTagTestOutput{
+		Content: in.Name,
+	}
+	return
+}
+
+func Test_Command_RootTag(t *testing.T) {
+	gtest.C(t, func(t *gtest.T) {
+		var (
+			ctx = gctx.New()
+		)
+		cmd, err := gcmd.NewFromObject(TestObjectForRootTag{})
+		t.AssertNil(err)
+
+		os.Args = []string{"root", "-n=john"}
+		value, err := cmd.RunWithValue(ctx)
+		t.AssertNil(err)
+		t.Assert(value, `{"Content":"john"}`)
+	})
+}