refactor cmd/config to internal

cmd/config/complete/complete.go

@@ -0,0 +1,68 @@
+// Copyright 2019 The Kubernetes Authors.
+// SPDX-License-Identifier: Apache-2.0
+
+package complete
+
+import (
+	"os"
+	"strings"
+
+	"github.com/posener/complete/v2"
+	"github.com/posener/complete/v2/predict"
+	"github.com/spf13/cobra"
+	"github.com/spf13/pflag"
+	"sigs.k8s.io/kustomize/cmd/config/internal/generateddocs/commands"
+	"sigs.k8s.io/kustomize/kyaml/errors"
+)
+
+// NewCommand returns a new install-completion command
+func NewCommand() *cobra.Command {
+	return &cobra.Command{
+		Use:     "install-completion",
+		Short:   commands.CompletionShort,
+		Long:    commands.CompletionLong,
+		PreRunE: preRunE,
+		Run:     run,
+	}
+}
+
+func preRunE(cmd *cobra.Command, args []string) error {
+	// install by default
+	if os.Getenv("COMP_INSTALL") == "" {
+		if err := errors.Wrap(os.Setenv("COMP_INSTALL", "1")); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func run(cmd *cobra.Command, args []string) {
+	// find the root command
+	for cmd.Parent() != nil {
+		cmd = cmd.Parent()
+	}
+
+	// do completion
+	Complete(cmd).Complete("kustomize")
+}
+
+// Complete returns a completion command for a cobra command
+func Complete(cmd *cobra.Command) *complete.Command {
+	cc := &complete.Command{
+		Flags: map[string]complete.Predictor{},
+		Sub:   map[string]*complete.Command{},
+	}
+
+	// add completion for each subcommand
+	for i := range cmd.Commands() {
+		c := cmd.Commands()[i]
+		name := strings.Split(c.Use, " ")[0]
+		cc.Sub[name] = Complete(c)
+	}
+
+	// add completion for each flag
+	cmd.Flags().VisitAll(func(flag *pflag.Flag) {
+		cc.Flags[flag.Name] = predict.Nothing
+	})
+	return cc
+}