Make rootCmd private

Update Cobra generator to make rootCmd private rather than
exporting it. Also update examples in README to use the exported
Execute() command rather than referencing unexported rootCmd.

Fixes #556

README.md

@@ -158,10 +158,7 @@ import (
 )
 
 func main() {
-  if err := cmd.RootCmd.Execute(); err != nil {
-    fmt.Println(err)
-    os.Exit(1)
-  }
+  cmd.Execute()
 }
 ```
 
@@ -174,7 +171,7 @@ commands you want. It's the easiest way to incorporate Cobra into your applicati
 
 ## Using the Cobra Library
 
-To manually implement Cobra you need to create a bare main.go file and a RootCmd file.
+To manually implement Cobra you need to create a bare main.go file and a rootCmd file.
 You will optionally provide additional commands as you see fit.
 
 ### Create rootCmd
@@ -184,7 +181,7 @@ Cobra doesn't require any special constructors. Simply create your commands.
 Ideally you place this in app/cmd/root.go:
 
 ```go
-var RootCmd = &cobra.Command{
+var rootCmd = &cobra.Command{
   Use:   "hugo",
   Short: "Hugo is a very fast static site generator",
   Long: `A Fast and Flexible Static Site Generator built with
@@ -212,14 +209,14 @@ import (
 
 func init() {
   cobra.OnInitialize(initConfig)
-  RootCmd.PersistentFlags().StringVar(&cfgFile, "config", "", "config file (default is $HOME/.cobra.yaml)")
-  RootCmd.PersistentFlags().StringVarP(&projectBase, "projectbase", "b", "", "base project directory eg. github.com/spf13/")
-  RootCmd.PersistentFlags().StringP("author", "a", "YOUR NAME", "Author name for copyright attribution")
-  RootCmd.PersistentFlags().StringVarP(&userLicense, "license", "l", "", "Name of license for the project (can provide `licensetext` in config)")
-  RootCmd.PersistentFlags().Bool("viper", true, "Use Viper for configuration")
-  viper.BindPFlag("author", RootCmd.PersistentFlags().Lookup("author"))
-  viper.BindPFlag("projectbase", RootCmd.PersistentFlags().Lookup("projectbase"))
-  viper.BindPFlag("useViper", RootCmd.PersistentFlags().Lookup("viper"))
+  rootCmd.PersistentFlags().StringVar(&cfgFile, "config", "", "config file (default is $HOME/.cobra.yaml)")
+  rootCmd.PersistentFlags().StringVarP(&projectBase, "projectbase", "b", "", "base project directory eg. github.com/spf13/")
+  rootCmd.PersistentFlags().StringP("author", "a", "YOUR NAME", "Author name for copyright attribution")
+  rootCmd.PersistentFlags().StringVarP(&userLicense, "license", "l", "", "Name of license for the project (can provide `licensetext` in config)")
+  rootCmd.PersistentFlags().Bool("viper", true, "Use Viper for configuration")
+  viper.BindPFlag("author", rootCmd.PersistentFlags().Lookup("author"))
+  viper.BindPFlag("projectbase", rootCmd.PersistentFlags().Lookup("projectbase"))
+  viper.BindPFlag("useViper", rootCmd.PersistentFlags().Lookup("viper"))
   viper.SetDefault("author", "NAME HERE <EMAIL ADDRESS>")
   viper.SetDefault("license", "apache")
 }
@@ -267,10 +264,7 @@ import (
 )
 
 func main() {
-  if err := cmd.RootCmd.Execute(); err != nil {
-    fmt.Println(err)
-    os.Exit(1)
-  }
+  cmd.Execute()
 }
 ```
 
@@ -292,7 +286,7 @@ import (
 )
 
 func init() {
-  RootCmd.AddCommand(versionCmd)
+  rootCmd.AddCommand(versionCmd)
 }
 
 var versionCmd = &cobra.Command{
@@ -329,7 +323,7 @@ command it's assigned to as well as every command under that command. For
 global flags, assign a flag as a persistent flag on the root.
 
 ```go
-RootCmd.PersistentFlags().BoolVarP(&Verbose, "verbose", "v", false, "verbose output")
+rootCmd.PersistentFlags().BoolVarP(&Verbose, "verbose", "v", false, "verbose output")
 ```
 
 ### Local Flags
@@ -337,7 +331,7 @@ RootCmd.PersistentFlags().BoolVarP(&Verbose, "verbose", "v", false, "verbose out
 A flag can also be assigned locally which will only apply to that specific command.
 
 ```go
-RootCmd.Flags().StringVarP(&Source, "source", "s", "", "Source directory to read from")
+rootCmd.Flags().StringVarP(&Source, "source", "s", "", "Source directory to read from")
 ```
 
 ### Local Flag on Parent Commands
@@ -360,8 +354,8 @@ You can also bind your flags with [viper](https://github.com/spf13/viper):
 var author string
 
 func init() {
-  RootCmd.PersistentFlags().StringVar(&author, "author", "YOUR NAME", "Author name for copyright attribution")
-  viper.BindPFlag("author", RootCmd.PersistentFlags().Lookup("author"))
+  rootCmd.PersistentFlags().StringVar(&author, "author", "YOUR NAME", "Author name for copyright attribution")
+  viper.BindPFlag("author", rootCmd.PersistentFlags().Lookup("author"))
 }
 ```
 

cobra/cmd/add.go

@@ -24,7 +24,7 @@ import (
 
 func init() {
 	addCmd.Flags().StringVarP(&packageName, "package", "t", "", "target package name (e.g. github.com/spf13/hugo)")
-	addCmd.Flags().StringVarP(&parentName, "parent", "p", "RootCmd", "variable name of parent command for this command")
+	addCmd.Flags().StringVarP(&parentName, "parent", "p", "rootCmd", "variable name of parent command for this command")
 }
 
 var packageName, parentName string
@@ -35,7 +35,7 @@ var addCmd = &cobra.Command{
 	Short:   "Add a command to a Cobra Application",
 	Long: `Add (cobra add) will create a new command, with a license and
 the appropriate structure for a Cobra-based CLI application,
-and register it to its parent (default RootCmd).
+and register it to its parent (default rootCmd).
 
 If you want your command to be public, pass in the command name
 with an initial uppercase letter.

cobra/cmd/init.go

@@ -150,8 +150,8 @@ import (
 
 var cfgFile string{{end}}
 
-// RootCmd represents the base command when called without any subcommands
-var RootCmd = &cobra.Command{
+// rootCmd represents the base command when called without any subcommands
+var rootCmd = &cobra.Command{
 	Use:   "{{.appName}}",
 	Short: "A brief description of your application",
 	Long: ` + "`" + `A longer description that spans multiple lines and likely contains
@@ -168,7 +168,7 @@ to quickly create a Cobra application.` + "`" + `,
 // Execute adds all child commands to the root command and sets flags appropriately.
 // This is called by main.main(). It only needs to happen once to the rootCmd.
 func Execute() {
-	if err := RootCmd.Execute(); err != nil {
+	if err := rootCmd.Execute(); err != nil {
 		fmt.Println(err)
 		os.Exit(1)
 	}
@@ -180,12 +180,12 @@ func init() { {{if .viper}}
 	// Here you will define your flags and configuration settings.
 	// Cobra supports persistent flags, which, if defined here,
 	// will be global for your application.{{ if .viper }}
-	RootCmd.PersistentFlags().StringVar(&cfgFile, "config", "", "config file (default is $HOME/.{{ .appName }}.yaml)"){{ else }}
-	// RootCmd.PersistentFlags().StringVar(&cfgFile, "config", "", "config file (default is $HOME/.{{ .appName }}.yaml)"){{ end }}
+	rootCmd.PersistentFlags().StringVar(&cfgFile, "config", "", "config file (default is $HOME/.{{ .appName }}.yaml)"){{ else }}
+	// rootCmd.PersistentFlags().StringVar(&cfgFile, "config", "", "config file (default is $HOME/.{{ .appName }}.yaml)"){{ end }}
 
 	// Cobra also supports local flags, which will only run
 	// when this action is called directly.
-	RootCmd.Flags().BoolP("toggle", "t", false, "Help message for toggle")
+	rootCmd.Flags().BoolP("toggle", "t", false, "Help message for toggle")
 }{{ if .viper }}
 
 // initConfig reads in config file and ENV variables if set.

cobra/cmd/testdata/root.go.golden

@@ -25,8 +25,8 @@ import (
 
 var cfgFile string
 
-// RootCmd represents the base command when called without any subcommands
-var RootCmd = &cobra.Command{
+// rootCmd represents the base command when called without any subcommands
+var rootCmd = &cobra.Command{
 	Use:   "testproject",
 	Short: "A brief description of your application",
 	Long: `A longer description that spans multiple lines and likely contains
@@ -43,7 +43,7 @@ to quickly create a Cobra application.`,
 // Execute adds all child commands to the root command and sets flags appropriately.
 // This is called by main.main(). It only needs to happen once to the rootCmd.
 func Execute() {
-	if err := RootCmd.Execute(); err != nil {
+	if err := rootCmd.Execute(); err != nil {
 		fmt.Println(err)
 		os.Exit(1)
 	}
@@ -55,11 +55,11 @@ func init() {
 	// Here you will define your flags and configuration settings.
 	// Cobra supports persistent flags, which, if defined here,
 	// will be global for your application.
-	RootCmd.PersistentFlags().StringVar(&cfgFile, "config", "", "config file (default is $HOME/.testproject.yaml)")
+	rootCmd.PersistentFlags().StringVar(&cfgFile, "config", "", "config file (default is $HOME/.testproject.yaml)")
 
 	// Cobra also supports local flags, which will only run
 	// when this action is called directly.
-	RootCmd.Flags().BoolP("toggle", "t", false, "Help message for toggle")
+	rootCmd.Flags().BoolP("toggle", "t", false, "Help message for toggle")
 }
 
 // initConfig reads in config file and ENV variables if set.

cobra/cmd/testdata/test.go.golden

@@ -36,7 +36,7 @@ to quickly create a Cobra application.`,
 }
 
 func init() {
-	RootCmd.AddCommand(testCmd)
+	rootCmd.AddCommand(testCmd)
 
 	// Here you will define your flags and configuration settings.