spf13/cobta completion example

main.go

// Package main is an example of using dynamic command-line completion with
// github.com/spf13/cobra.
package main

import (
	"fmt"
	"os"
	"time"

	"github.com/spf13/cobra"
)

// C is a cobra.Command
type C = cobra.Command

// ValidShells are the shells for which we can generate completion
var ValidShells = []string{"bash", "zsh", "fish", "powershell"}

func completion() *C {
	cmd := &C{
		Use:       "completion",
		Short:     "Complete a programme",
		Long:      `An awesome completer`,
		Args:      cobra.ExactValidArgs(1),
		ValidArgs: ValidShells,
		Run: func(c *C, a []string) {
			if len(a) != 1 {
				panic("too many args")
			}
			switch a[0] {
			case "bash":
				c.Root().GenBashCompletion(c.OutOrStdout())
			case "zsh":
				c.Root().GenZshCompletion(c.OutOrStdout())
			case "fish":
				c.Root().GenFishCompletion(c.OutOrStdout(), true)
			case "powershell":
				c.Root().GenPowerShellCompletion(os.Stdout)
			}
		},
	}
	return cmd
}

var validFoos = func() func(*C, []string, string) ([]string, cobra.ShellCompDirective) {
	return func(cmd *cobra.Command, args []string, toComplete string) ([]string, cobra.ShellCompDirective) {
		return []string{"foo", "bar", time.Now().String()}, cobra.ShellCompDirectiveNoFileComp
	}
}

func foo() *C {
	cmd := &C{
		Use:               "foo",
		Short:             "A foo",
		Long:              `An awesome foo`,
		Args:              cobra.ExactValidArgs(1),
		ValidArgsFunction: validFoos(),
		Run: func(c *C, a []string) {
			fmt.Fprintf(c.OutOrStdout(), "Foo! %v\n", a)
		},
	}
	return cmd
}

func cmd() *C {
	cmd := &C{
		Use:     "snake",
		Version: "0.0.1",
		Short:   "A programme",
		Long:    `An awesome programme`,
		Run: func(c *C, a []string) {
			fmt.Fprintf(c.OutOrStdout(), "Hello!\n")
		},
	}

	cmd.AddCommand(completion(), foo())

	return cmd
}

func main() {
	cmd().Execute()
}