printing helpful shorthand command (#816)

* printing helpful shorthand command

* Addressed review comments

* Resolved rebase conflicts

* Using cmd.Root().Name() for getting the executable name

cmd/create.go

@@ -113,7 +113,7 @@ func runCreate(cmd *cobra.Command, args []string, newClient ClientFactory) (err
 	// Config
 	// Create a config based on args.  Also uses the newClient to create a
 	// temporary client for completing options such as available runtimes.
-	cfg, err := newCreateConfig(args, newClient)
+	cfg, err := newCreateConfig(cmd, args, newClient)
 	if err != nil {
 		return
 	}
@@ -159,7 +159,7 @@ func runCreateHelp(cmd *cobra.Command, args []string, newClient ClientFactory) {
 
 	tpl := createHelpTemplate(cmd)
 
-	cfg, err := newCreateConfig(args, newClient)
+	cfg, err := newCreateConfig(cmd, args, newClient)
 	failSoft(err)
 
 	client := newClient(createConfigToClientOptions(cfg))
@@ -210,7 +210,7 @@ type createConfig struct {
 // The client constructor function is used to create a transient client for
 // accessing things like the current valid templates list, and uses the
 // current value of the config at time of prompting.
-func newCreateConfig(args []string, newClient ClientFactory) (cfg createConfig, err error) {
+func newCreateConfig(cmd *cobra.Command, args []string, newClient ClientFactory) (cfg createConfig, err error) {
 	var (
 		path         string
 		dirName      string
@@ -259,7 +259,13 @@ func newCreateConfig(args []string, newClient ClientFactory) (cfg createConfig,
 
 	// IN confirm mode.  If also in an interactive terminal, run prompts.
 	if interactiveTerminal() {
-		return cfg.prompt(client)
+		createdCfg, err := cfg.prompt(client)
+		if err != nil {
+			return createdCfg, err
+		}
+		fmt.Println("Command:")
+		fmt.Println(singleCommand(cmd, args, createdCfg))
+		return createdCfg, nil
 	}
 
 	// Confirming, but noninteractive
@@ -278,6 +284,26 @@ func newCreateConfig(args []string, newClient ClientFactory) (cfg createConfig,
 	return
 }
 
+// singleCommand that could be used by the current user to minimally recreate the current state.
+func singleCommand(cmd *cobra.Command, args []string, cfg createConfig) string {
+	var b strings.Builder
+	b.WriteString(cmd.Root().Name())    // process executable
+	b.WriteString(" -l " + cfg.Runtime) // language runtime is required
+	if cmd.Flags().Lookup("template").Changed {
+		b.WriteString(" -t " + cfg.Template)
+	}
+	if cmd.Flags().Lookup("repository").Changed {
+		b.WriteString(" -r " + cfg.Repository)
+	}
+	if cmd.Flags().Lookup("verbose").Changed {
+		b.WriteString(fmt.Sprintf(" -v %v", cfg.Verbose))
+	}
+	if len(args) > 0 {
+		b.WriteString(" " + cfg.Path) // optional trailing <path> argument
+	}
+	return b.String()
+}
+
 // Validate the current state of the config, returning any errors.
 // Note this is a deeper validation using a client already configured with a
 // preliminary config object from flags/config, such that the client instance
@@ -477,7 +503,7 @@ type flagCompletionFunc func(*cobra.Command, []string, string) ([]string, cobra.
 
 func newRuntimeCompletionFunc(newClient ClientFactory) flagCompletionFunc {
 	return func(cmd *cobra.Command, args []string, toComplete string) ([]string, cobra.ShellCompDirective) {
-		cfg, err := newCreateConfig(args, newClient)
+		cfg, err := newCreateConfig(cmd, args, newClient)
 		if err != nil {
 			fmt.Fprintf(os.Stderr, "error creating client config for flag completion: %v", err)
 		}
@@ -488,7 +514,7 @@ func newRuntimeCompletionFunc(newClient ClientFactory) flagCompletionFunc {
 
 func newTemplateCompletionFunc(newClient ClientFactory) flagCompletionFunc {
 	return func(cmd *cobra.Command, args []string, toComplete string) ([]string, cobra.ShellCompDirective) {
-		cfg, err := newCreateConfig(args, newClient)
+		cfg, err := newCreateConfig(cmd, args, newClient)
 		if err != nil {
 			fmt.Fprintf(os.Stderr, "error creating client config for flag completion: %v", err)
 		}