remove cobra v2 completion for plugins

Signed-off-by: CrazyMax <crazy-max@users.noreply.github.com>

Author: crazy-max

cmd/docker/docker.go

@@ -133,13 +133,20 @@ func tryRunPluginHelp(dockerCli command.Cli, ccmd *cobra.Command, cargs []string
 func setHelpFunc(dockerCli command.Cli, cmd *cobra.Command) {
 	defaultHelpFunc := cmd.HelpFunc()
 	cmd.SetHelpFunc(func(ccmd *cobra.Command, args []string) {
-		if pluginmanager.IsPluginCommand(ccmd) {
+		if err := pluginmanager.AddPluginCommandStubs(dockerCli, ccmd.Root()); err != nil {
+			ccmd.Println(err)
+			return
+		}
+
+		if len(args) >= 1 {
 			err := tryRunPluginHelp(dockerCli, ccmd, args)
+			if err == nil {
+				return
+			}
 			if !pluginmanager.IsNotFound(err) {
 				ccmd.Println(err)
+				return
 			}
-			cmd.PrintErrf("unknown help topic: %v\n", ccmd.Name())
-			return
 		}
 
 		if err := isSupported(ccmd, dockerCli); err != nil {
@@ -227,14 +234,8 @@ func runDocker(dockerCli *command.DockerCli) error {
 		return err
 	}
 
-	err = pluginmanager.AddPluginCommandStubs(dockerCli, cmd)
-	if err != nil {
-		return err
-	}
-
 	if len(args) > 0 {
-		ccmd, _, err := cmd.Find(args)
-		if err != nil || pluginmanager.IsPluginCommand(ccmd) {
+		if _, _, err := cmd.Find(args); err != nil {
 			err := tryPluginRun(dockerCli, cmd, args[0], envs)
 			if !pluginmanager.IsNotFound(err) {
 				return err

e2e/cli-plugins/run_test.go

@@ -97,7 +97,7 @@ func TestBadHelp(t *testing.T) {
 
 	res := icmd.RunCmd(run("badmeta", "--help"))
 	res.Assert(t, icmd.Expected{
-		ExitCode: 0,
+		ExitCode: 1,
 		// This should be literally the whole docker help
 		// output, so spot check instead of a golden with
 		// everything in which will change all the time.