Adding upstream version 1.8.0.upstream/1.8.0upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 3519 insertions, 0 deletions

diff --git a/completions_test.go b/completions_test.go
new file mode 100644
index 0000000..d5aee25
--- /dev/null
+++ b/completions_test.go
@@ -0,0 +1,3519 @@
+// Copyright 2013-2023 The Cobra Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package cobra
+
+import (
+	"bytes"
+	"context"
+	"fmt"
+	"strings"
+	"sync"
+	"testing"
+)
+
+func validArgsFunc(cmd *Command, args []string, toComplete string) ([]string, ShellCompDirective) {
+	if len(args) != 0 {
+		return nil, ShellCompDirectiveNoFileComp
+	}
+
+	var completions []string
+	for _, comp := range []string{"one\tThe first", "two\tThe second"} {
+		if strings.HasPrefix(comp, toComplete) {
+			completions = append(completions, comp)
+		}
+	}
+	return completions, ShellCompDirectiveDefault
+}
+
+func validArgsFunc2(cmd *Command, args []string, toComplete string) ([]string, ShellCompDirective) {
+	if len(args) != 0 {
+		return nil, ShellCompDirectiveNoFileComp
+	}
+
+	var completions []string
+	for _, comp := range []string{"three\tThe third", "four\tThe fourth"} {
+		if strings.HasPrefix(comp, toComplete) {
+			completions = append(completions, comp)
+		}
+	}
+	return completions, ShellCompDirectiveDefault
+}
+
+func TestCmdNameCompletionInGo(t *testing.T) {
+	rootCmd := &Command{
+		Use: "root",
+		Run: emptyRun,
+	}
+	childCmd1 := &Command{
+		Use:   "firstChild",
+		Short: "First command",
+		Run:   emptyRun,
+	}
+	childCmd2 := &Command{
+		Use: "secondChild",
+		Run: emptyRun,
+	}
+	hiddenCmd := &Command{
+		Use:    "testHidden",
+		Hidden: true, // Not completed
+		Run:    emptyRun,
+	}
+	deprecatedCmd := &Command{
+		Use:        "testDeprecated",
+		Deprecated: "deprecated", // Not completed
+		Run:        emptyRun,
+	}
+	aliasedCmd := &Command{
+		Use:     "aliased",
+		Short:   "A command with aliases",
+		Aliases: []string{"testAlias", "testSynonym"}, // Not completed
+		Run:     emptyRun,
+	}
+
+	rootCmd.AddCommand(childCmd1, childCmd2, hiddenCmd, deprecatedCmd, aliasedCmd)
+
+	// Test that sub-command names are completed
+	output, err := executeCommand(rootCmd, ShellCompNoDescRequestCmd, "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected := strings.Join([]string{
+		"aliased",
+		"completion",
+		"firstChild",
+		"help",
+		"secondChild",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test that sub-command names are completed with prefix
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "s")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"secondChild",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test that even with no valid sub-command matches, hidden, deprecated and
+	// aliases are not completed
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "test")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test that sub-command names are completed with description
+	output, err = executeCommand(rootCmd, ShellCompRequestCmd, "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"aliased\tA command with aliases",
+		"completion\tGenerate the autocompletion script for the specified shell",
+		"firstChild\tFirst command",
+		"help\tHelp about any command",
+		"secondChild",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+}
+
+func TestNoCmdNameCompletionInGo(t *testing.T) {
+	rootCmd := &Command{
+		Use: "root",
+		Run: emptyRun,
+	}
+	rootCmd.Flags().String("localroot", "", "local root flag")
+
+	childCmd1 := &Command{
+		Use:   "childCmd1",
+		Short: "First command",
+		Args:  MinimumNArgs(0),
+		Run:   emptyRun,
+	}
+	rootCmd.AddCommand(childCmd1)
+	childCmd1.PersistentFlags().StringP("persistent", "p", "", "persistent flag")
+	persistentFlag := childCmd1.PersistentFlags().Lookup("persistent")
+	childCmd1.Flags().StringP("nonPersistent", "n", "", "non-persistent flag")
+	nonPersistentFlag := childCmd1.Flags().Lookup("nonPersistent")
+
+	childCmd2 := &Command{
+		Use: "childCmd2",
+		Run: emptyRun,
+	}
+	childCmd1.AddCommand(childCmd2)
+
+	// Test that sub-command names are not completed if there is an argument already
+	output, err := executeCommand(rootCmd, ShellCompNoDescRequestCmd, "childCmd1", "arg1", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected := strings.Join([]string{
+		":0",
+		"Completion ended with directive: ShellCompDirectiveDefault", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test that sub-command names are not completed if a local non-persistent flag is present
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "childCmd1", "--nonPersistent", "value", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+	// Reset the flag for the next command
+	nonPersistentFlag.Changed = false
+
+	expected = strings.Join([]string{
+		":0",
+		"Completion ended with directive: ShellCompDirectiveDefault", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test that sub-command names are completed if a local non-persistent flag is present and TraverseChildren is set to true
+	// set TraverseChildren to true on the root cmd
+	rootCmd.TraverseChildren = true
+
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "--localroot", "value", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+	// Reset TraverseChildren for next command
+	rootCmd.TraverseChildren = false
+
+	expected = strings.Join([]string{
+		"childCmd1",
+		"completion",
+		"help",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test that sub-command names from a child cmd are completed if a local non-persistent flag is present
+	// and TraverseChildren is set to true on the root cmd
+	rootCmd.TraverseChildren = true
+
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "--localroot", "value", "childCmd1", "--nonPersistent", "value", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+	// Reset TraverseChildren for next command
+	rootCmd.TraverseChildren = false
+	// Reset the flag for the next command
+	nonPersistentFlag.Changed = false
+
+	expected = strings.Join([]string{
+		"childCmd2",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test that we don't use Traverse when we shouldn't.
+	// This command should not return a completion since the command line is invalid without TraverseChildren.
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "--localroot", "value", "childCmd1", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		":0",
+		"Completion ended with directive: ShellCompDirectiveDefault", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test that sub-command names are not completed if a local non-persistent short flag is present
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "childCmd1", "-n", "value", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+	// Reset the flag for the next command
+	nonPersistentFlag.Changed = false
+
+	expected = strings.Join([]string{
+		":0",
+		"Completion ended with directive: ShellCompDirectiveDefault", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test that sub-command names are completed with a persistent flag
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "childCmd1", "--persistent", "value", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+	// Reset the flag for the next command
+	persistentFlag.Changed = false
+
+	expected = strings.Join([]string{
+		"childCmd2",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test that sub-command names are completed with a persistent short flag
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "childCmd1", "-p", "value", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+	// Reset the flag for the next command
+	persistentFlag.Changed = false
+
+	expected = strings.Join([]string{
+		"childCmd2",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+}
+
+func TestValidArgsCompletionInGo(t *testing.T) {
+	rootCmd := &Command{
+		Use:       "root",
+		ValidArgs: []string{"one", "two", "three"},
+		Args:      MinimumNArgs(1),
+	}
+
+	// Test that validArgs are completed
+	output, err := executeCommand(rootCmd, ShellCompNoDescRequestCmd, "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected := strings.Join([]string{
+		"one",
+		"two",
+		"three",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test that validArgs are completed with prefix
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "o")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"one",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test that validArgs don't repeat
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "one", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		":0",
+		"Completion ended with directive: ShellCompDirectiveDefault", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+}
+
+func TestValidArgsAndCmdCompletionInGo(t *testing.T) {
+	rootCmd := &Command{
+		Use:       "root",
+		ValidArgs: []string{"one", "two"},
+		Run:       emptyRun,
+	}
+
+	childCmd := &Command{
+		Use: "thechild",
+		Run: emptyRun,
+	}
+
+	rootCmd.AddCommand(childCmd)
+
+	// Test that both sub-commands and validArgs are completed
+	output, err := executeCommand(rootCmd, ShellCompNoDescRequestCmd, "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected := strings.Join([]string{
+		"completion",
+		"help",
+		"thechild",
+		"one",
+		"two",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test that both sub-commands and validArgs are completed with prefix
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "t")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"thechild",
+		"two",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+}
+
+func TestValidArgsFuncAndCmdCompletionInGo(t *testing.T) {
+	rootCmd := &Command{
+		Use:               "root",
+		ValidArgsFunction: validArgsFunc,
+		Run:               emptyRun,
+	}
+
+	childCmd := &Command{
+		Use:   "thechild",
+		Short: "The child command",
+		Run:   emptyRun,
+	}
+
+	rootCmd.AddCommand(childCmd)
+
+	// Test that both sub-commands and validArgsFunction are completed
+	output, err := executeCommand(rootCmd, ShellCompNoDescRequestCmd, "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected := strings.Join([]string{
+		"completion",
+		"help",
+		"thechild",
+		"one",
+		"two",
+		":0",
+		"Completion ended with directive: ShellCompDirectiveDefault", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test that both sub-commands and validArgs are completed with prefix
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "t")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"thechild",
+		"two",
+		":0",
+		"Completion ended with directive: ShellCompDirectiveDefault", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test that both sub-commands and validArgs are completed with description
+	output, err = executeCommand(rootCmd, ShellCompRequestCmd, "t")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"thechild\tThe child command",
+		"two\tThe second",
+		":0",
+		"Completion ended with directive: ShellCompDirectiveDefault", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+}
+
+func TestFlagNameCompletionInGo(t *testing.T) {
+	rootCmd := &Command{
+		Use: "root",
+		Run: emptyRun,
+	}
+	childCmd := &Command{
+		Use:     "childCmd",
+		Version: "1.2.3",
+		Run:     emptyRun,
+	}
+	rootCmd.AddCommand(childCmd)
+
+	rootCmd.Flags().IntP("first", "f", -1, "first flag")
+	rootCmd.PersistentFlags().BoolP("second", "s", false, "second flag")
+	childCmd.Flags().String("subFlag", "", "sub flag")
+
+	// Test that flag names are not shown if the user has not given the '-' prefix
+	output, err := executeCommand(rootCmd, ShellCompNoDescRequestCmd, "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected := strings.Join([]string{
+		"childCmd",
+		"completion",
+		"help",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test that flag names are completed
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "-")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"--first",
+		"-f",
+		"--help",
+		"-h",
+		"--second",
+		"-s",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test that flag names are completed when a prefix is given
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "--f")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"--first",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test that flag names are completed in a sub-cmd
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "childCmd", "-")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"--second",
+		"-s",
+		"--help",
+		"-h",
+		"--subFlag",
+		"--version",
+		"-v",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+}
+
+func TestFlagNameCompletionInGoWithDesc(t *testing.T) {
+	rootCmd := &Command{
+		Use: "root",
+		Run: emptyRun,
+	}
+	childCmd := &Command{
+		Use:     "childCmd",
+		Short:   "first command",
+		Version: "1.2.3",
+		Run:     emptyRun,
+	}
+	rootCmd.AddCommand(childCmd)
+
+	rootCmd.Flags().IntP("first", "f", -1, "first flag\nlonger description for flag")
+	rootCmd.PersistentFlags().BoolP("second", "s", false, "second flag")
+	childCmd.Flags().String("subFlag", "", "sub flag")
+
+	// Test that flag names are not shown if the user has not given the '-' prefix
+	output, err := executeCommand(rootCmd, ShellCompRequestCmd, "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected := strings.Join([]string{
+		"childCmd\tfirst command",
+		"completion\tGenerate the autocompletion script for the specified shell",
+		"help\tHelp about any command",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test that flag names are completed
+	output, err = executeCommand(rootCmd, ShellCompRequestCmd, "-")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"--first\tfirst flag",
+		"-f\tfirst flag",
+		"--help\thelp for root",
+		"-h\thelp for root",
+		"--second\tsecond flag",
+		"-s\tsecond flag",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test that flag names are completed when a prefix is given
+	output, err = executeCommand(rootCmd, ShellCompRequestCmd, "--f")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"--first\tfirst flag",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test that flag names are completed in a sub-cmd
+	output, err = executeCommand(rootCmd, ShellCompRequestCmd, "childCmd", "-")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"--second\tsecond flag",
+		"-s\tsecond flag",
+		"--help\thelp for childCmd",
+		"-h\thelp for childCmd",
+		"--subFlag\tsub flag",
+		"--version\tversion for childCmd",
+		"-v\tversion for childCmd",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+}
+
+func TestFlagNameCompletionRepeat(t *testing.T) {
+	rootCmd := &Command{
+		Use: "root",
+		Run: emptyRun,
+	}
+	childCmd := &Command{
+		Use:   "childCmd",
+		Short: "first command",
+		Run:   emptyRun,
+	}
+	rootCmd.AddCommand(childCmd)
+
+	rootCmd.Flags().IntP("first", "f", -1, "first flag")
+	firstFlag := rootCmd.Flags().Lookup("first")
+	rootCmd.Flags().BoolP("second", "s", false, "second flag")
+	secondFlag := rootCmd.Flags().Lookup("second")
+	rootCmd.Flags().StringArrayP("array", "a", nil, "array flag")
+	arrayFlag := rootCmd.Flags().Lookup("array")
+	rootCmd.Flags().IntSliceP("slice", "l", nil, "slice flag")
+	sliceFlag := rootCmd.Flags().Lookup("slice")
+	rootCmd.Flags().BoolSliceP("bslice", "b", nil, "bool slice flag")
+	bsliceFlag := rootCmd.Flags().Lookup("bslice")
+
+	// Test that flag names are not repeated unless they are an array or slice
+	output, err := executeCommand(rootCmd, ShellCompNoDescRequestCmd, "--first", "1", "--")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+	// Reset the flag for the next command
+	firstFlag.Changed = false
+
+	expected := strings.Join([]string{
+		"--array",
+		"--bslice",
+		"--help",
+		"--second",
+		"--slice",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test that flag names are not repeated unless they are an array or slice
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "--first", "1", "--second=false", "--")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+	// Reset the flag for the next command
+	firstFlag.Changed = false
+	secondFlag.Changed = false
+
+	expected = strings.Join([]string{
+		"--array",
+		"--bslice",
+		"--help",
+		"--slice",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test that flag names are not repeated unless they are an array or slice
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "--slice", "1", "--slice=2", "--array", "val", "--bslice", "true", "--")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+	// Reset the flag for the next command
+	sliceFlag.Changed = false
+	arrayFlag.Changed = false
+	bsliceFlag.Changed = false
+
+	expected = strings.Join([]string{
+		"--array",
+		"--bslice",
+		"--first",
+		"--help",
+		"--second",
+		"--slice",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test that flag names are not repeated unless they are an array or slice, using shortname
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "-l", "1", "-l=2", "-a", "val", "-")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+	// Reset the flag for the next command
+	sliceFlag.Changed = false
+	arrayFlag.Changed = false
+
+	expected = strings.Join([]string{
+		"--array",
+		"-a",
+		"--bslice",
+		"-b",
+		"--first",
+		"-f",
+		"--help",
+		"-h",
+		"--second",
+		"-s",
+		"--slice",
+		"-l",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test that flag names are not repeated unless they are an array or slice, using shortname with prefix
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "-l", "1", "-l=2", "-a", "val", "-a")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+	// Reset the flag for the next command
+	sliceFlag.Changed = false
+	arrayFlag.Changed = false
+
+	expected = strings.Join([]string{
+		"-a",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+}
+
+func TestRequiredFlagNameCompletionInGo(t *testing.T) {
+	rootCmd := &Command{
+		Use:       "root",
+		ValidArgs: []string{"realArg"},
+		Run:       emptyRun,
+	}
+	childCmd := &Command{
+		Use: "childCmd",
+		ValidArgsFunction: func(cmd *Command, args []string, toComplete string) ([]string, ShellCompDirective) {
+			return []string{"subArg"}, ShellCompDirectiveNoFileComp
+		},
+		Run: emptyRun,
+	}
+	rootCmd.AddCommand(childCmd)
+
+	rootCmd.Flags().IntP("requiredFlag", "r", -1, "required flag")
+	assertNoErr(t, rootCmd.MarkFlagRequired("requiredFlag"))
+	requiredFlag := rootCmd.Flags().Lookup("requiredFlag")
+
+	rootCmd.PersistentFlags().IntP("requiredPersistent", "p", -1, "required persistent")
+	assertNoErr(t, rootCmd.MarkPersistentFlagRequired("requiredPersistent"))
+	requiredPersistent := rootCmd.PersistentFlags().Lookup("requiredPersistent")
+
+	rootCmd.Flags().StringP("release", "R", "", "Release name")
+
+	childCmd.Flags().BoolP("subRequired", "s", false, "sub required flag")
+	assertNoErr(t, childCmd.MarkFlagRequired("subRequired"))
+	childCmd.Flags().BoolP("subNotRequired", "n", false, "sub not required flag")
+
+	// Test that a required flag is suggested even without the - prefix
+	output, err := executeCommand(rootCmd, ShellCompNoDescRequestCmd, "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected := strings.Join([]string{
+		"childCmd",
+		"completion",
+		"help",
+		"--requiredFlag",
+		"-r",
+		"--requiredPersistent",
+		"-p",
+		"realArg",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test that a required flag is suggested without other flags when using the '-' prefix
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "-")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"--requiredFlag",
+		"-r",
+		"--requiredPersistent",
+		"-p",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test that if no required flag matches, the normal flags are suggested
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "--relea")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"--release",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test required flags for sub-commands
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "childCmd", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"--requiredPersistent",
+		"-p",
+		"--subRequired",
+		"-s",
+		"subArg",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "childCmd", "-")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"--requiredPersistent",
+		"-p",
+		"--subRequired",
+		"-s",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "childCmd", "--subNot")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"--subNotRequired",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test that when a required flag is present, it is not suggested anymore
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "--requiredFlag", "1", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+	// Reset the flag for the next command
+	requiredFlag.Changed = false
+
+	expected = strings.Join([]string{
+		"--requiredPersistent",
+		"-p",
+		"realArg",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test that when a persistent required flag is present, it is not suggested anymore
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "--requiredPersistent", "1", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+	// Reset the flag for the next command
+	requiredPersistent.Changed = false
+
+	expected = strings.Join([]string{
+		"childCmd",
+		"completion",
+		"help",
+		"--requiredFlag",
+		"-r",
+		"realArg",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test that when all required flags are present, normal completion is done
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "--requiredFlag", "1", "--requiredPersistent", "1", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+	// Reset the flags for the next command
+	requiredFlag.Changed = false
+	requiredPersistent.Changed = false
+
+	expected = strings.Join([]string{
+		"realArg",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+}
+
+func TestFlagFileExtFilterCompletionInGo(t *testing.T) {
+	rootCmd := &Command{
+		Use: "root",
+		Run: emptyRun,
+	}
+
+	// No extensions.  Should be ignored.
+	rootCmd.Flags().StringP("file", "f", "", "file flag")
+	assertNoErr(t, rootCmd.MarkFlagFilename("file"))
+
+	// Single extension
+	rootCmd.Flags().StringP("log", "l", "", "log flag")
+	assertNoErr(t, rootCmd.MarkFlagFilename("log", "log"))
+
+	// Multiple extensions
+	rootCmd.Flags().StringP("yaml", "y", "", "yaml flag")
+	assertNoErr(t, rootCmd.MarkFlagFilename("yaml", "yaml", "yml"))
+
+	// Directly using annotation
+	rootCmd.Flags().StringP("text", "t", "", "text flag")
+	assertNoErr(t, rootCmd.Flags().SetAnnotation("text", BashCompFilenameExt, []string{"txt"}))
+
+	// Test that the completion logic returns the proper info for the completion
+	// script to handle the file filtering
+	output, err := executeCommand(rootCmd, ShellCompNoDescRequestCmd, "--file", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected := strings.Join([]string{
+		":0",
+		"Completion ended with directive: ShellCompDirectiveDefault", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "--log", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"log",
+		":8",
+		"Completion ended with directive: ShellCompDirectiveFilterFileExt", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "--yaml", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"yaml", "yml",
+		":8",
+		"Completion ended with directive: ShellCompDirectiveFilterFileExt", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "--yaml=")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"yaml", "yml",
+		":8",
+		"Completion ended with directive: ShellCompDirectiveFilterFileExt", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "-y", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"yaml", "yml",
+		":8",
+		"Completion ended with directive: ShellCompDirectiveFilterFileExt", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "-y=")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"yaml", "yml",
+		":8",
+		"Completion ended with directive: ShellCompDirectiveFilterFileExt", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "--text", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"txt",
+		":8",
+		"Completion ended with directive: ShellCompDirectiveFilterFileExt", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+}
+
+func TestFlagDirFilterCompletionInGo(t *testing.T) {
+	rootCmd := &Command{
+		Use: "root",
+		Run: emptyRun,
+	}
+
+	// Filter directories
+	rootCmd.Flags().StringP("dir", "d", "", "dir flag")
+	assertNoErr(t, rootCmd.MarkFlagDirname("dir"))
+
+	// Filter directories within a directory
+	rootCmd.Flags().StringP("subdir", "s", "", "subdir")
+	assertNoErr(t, rootCmd.Flags().SetAnnotation("subdir", BashCompSubdirsInDir, []string{"themes"}))
+
+	// Multiple directory specification get ignored
+	rootCmd.Flags().StringP("manydir", "m", "", "manydir")
+	assertNoErr(t, rootCmd.Flags().SetAnnotation("manydir", BashCompSubdirsInDir, []string{"themes", "colors"}))
+
+	// Test that the completion logic returns the proper info for the completion
+	// script to handle the directory filtering
+	output, err := executeCommand(rootCmd, ShellCompNoDescRequestCmd, "--dir", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected := strings.Join([]string{
+		":16",
+		"Completion ended with directive: ShellCompDirectiveFilterDirs", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "-d", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		":16",
+		"Completion ended with directive: ShellCompDirectiveFilterDirs", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "--subdir", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"themes",
+		":16",
+		"Completion ended with directive: ShellCompDirectiveFilterDirs", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "--subdir=")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"themes",
+		":16",
+		"Completion ended with directive: ShellCompDirectiveFilterDirs", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "-s", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"themes",
+		":16",
+		"Completion ended with directive: ShellCompDirectiveFilterDirs", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "-s=")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"themes",
+		":16",
+		"Completion ended with directive: ShellCompDirectiveFilterDirs", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "--manydir", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		":16",
+		"Completion ended with directive: ShellCompDirectiveFilterDirs", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+}
+
+func TestValidArgsFuncCmdContext(t *testing.T) {
+	validArgsFunc := func(cmd *Command, args []string, toComplete string) ([]string, ShellCompDirective) {
+		ctx := cmd.Context()
+
+		if ctx == nil {
+			t.Error("Received nil context in completion func")
+		} else if ctx.Value("testKey") != "123" {
+			t.Error("Received invalid context")
+		}
+
+		return nil, ShellCompDirectiveDefault
+	}
+
+	rootCmd := &Command{
+		Use: "root",
+		Run: emptyRun,
+	}
+	childCmd := &Command{
+		Use:               "childCmd",
+		ValidArgsFunction: validArgsFunc,
+		Run:               emptyRun,
+	}
+	rootCmd.AddCommand(childCmd)
+
+	//nolint:golint,staticcheck // We can safely use a basic type as key in tests.
+	ctx := context.WithValue(context.Background(), "testKey", "123")
+
+	// Test completing an empty string on the childCmd
+	_, output, err := executeCommandWithContextC(ctx, rootCmd, ShellCompNoDescRequestCmd, "childCmd", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected := strings.Join([]string{
+		":0",
+		"Completion ended with directive: ShellCompDirectiveDefault", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+}
+
+func TestValidArgsFuncSingleCmd(t *testing.T) {
+	rootCmd := &Command{
+		Use:               "root",
+		ValidArgsFunction: validArgsFunc,
+		Run:               emptyRun,
+	}
+
+	// Test completing an empty string
+	output, err := executeCommand(rootCmd, ShellCompNoDescRequestCmd, "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected := strings.Join([]string{
+		"one",
+		"two",
+		":0",
+		"Completion ended with directive: ShellCompDirectiveDefault", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Check completing with a prefix
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "t")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"two",
+		":0",
+		"Completion ended with directive: ShellCompDirectiveDefault", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+}
+
+func TestValidArgsFuncSingleCmdInvalidArg(t *testing.T) {
+	rootCmd := &Command{
+		Use: "root",
+		// If we don't specify a value for Args, this test fails.
+		// This is only true for a root command without any subcommands, and is caused
+		// by the fact that the __complete command becomes a subcommand when there should not be one.
+		// The problem is in the implementation of legacyArgs().
+		Args:              MinimumNArgs(1),
+		ValidArgsFunction: validArgsFunc,
+		Run:               emptyRun,
+	}
+
+	// Check completing with wrong number of args
+	output, err := executeCommand(rootCmd, ShellCompNoDescRequestCmd, "unexpectedArg", "t")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected := strings.Join([]string{
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+}
+
+func TestValidArgsFuncChildCmds(t *testing.T) {
+	rootCmd := &Command{Use: "root", Args: NoArgs, Run: emptyRun}
+	child1Cmd := &Command{
+		Use:               "child1",
+		ValidArgsFunction: validArgsFunc,
+		Run:               emptyRun,
+	}
+	child2Cmd := &Command{
+		Use:               "child2",
+		ValidArgsFunction: validArgsFunc2,
+		Run:               emptyRun,
+	}
+	rootCmd.AddCommand(child1Cmd, child2Cmd)
+
+	// Test completion of first sub-command with empty argument
+	output, err := executeCommand(rootCmd, ShellCompNoDescRequestCmd, "child1", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected := strings.Join([]string{
+		"one",
+		"two",
+		":0",
+		"Completion ended with directive: ShellCompDirectiveDefault", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test completion of first sub-command with a prefix to complete
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "child1", "t")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"two",
+		":0",
+		"Completion ended with directive: ShellCompDirectiveDefault", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Check completing with wrong number of args
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "child1", "unexpectedArg", "t")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test completion of second sub-command with empty argument
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "child2", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"three",
+		"four",
+		":0",
+		"Completion ended with directive: ShellCompDirectiveDefault", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "child2", "t")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"three",
+		":0",
+		"Completion ended with directive: ShellCompDirectiveDefault", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Check completing with wrong number of args
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "child2", "unexpectedArg", "t")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+}
+
+func TestValidArgsFuncAliases(t *testing.T) {
+	rootCmd := &Command{Use: "root", Args: NoArgs, Run: emptyRun}
+	child := &Command{
+		Use:               "child",
+		Aliases:           []string{"son", "daughter"},
+		ValidArgsFunction: validArgsFunc,
+		Run:               emptyRun,
+	}
+	rootCmd.AddCommand(child)
+
+	// Test completion of first sub-command with empty argument
+	output, err := executeCommand(rootCmd, ShellCompNoDescRequestCmd, "son", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected := strings.Join([]string{
+		"one",
+		"two",
+		":0",
+		"Completion ended with directive: ShellCompDirectiveDefault", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test completion of first sub-command with a prefix to complete
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "daughter", "t")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"two",
+		":0",
+		"Completion ended with directive: ShellCompDirectiveDefault", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Check completing with wrong number of args
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "son", "unexpectedArg", "t")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+}
+
+func TestValidArgsFuncInBashScript(t *testing.T) {
+	rootCmd := &Command{Use: "root", Args: NoArgs, Run: emptyRun}
+	child := &Command{
+		Use:               "child",
+		ValidArgsFunction: validArgsFunc,
+		Run:               emptyRun,
+	}
+	rootCmd.AddCommand(child)
+
+	buf := new(bytes.Buffer)
+	assertNoErr(t, rootCmd.GenBashCompletion(buf))
+	output := buf.String()
+
+	check(t, output, "has_completion_function=1")
+}
+
+func TestNoValidArgsFuncInBashScript(t *testing.T) {
+	rootCmd := &Command{Use: "root", Args: NoArgs, Run: emptyRun}
+	child := &Command{
+		Use: "child",
+		Run: emptyRun,
+	}
+	rootCmd.AddCommand(child)
+
+	buf := new(bytes.Buffer)
+	assertNoErr(t, rootCmd.GenBashCompletion(buf))
+	output := buf.String()
+
+	checkOmit(t, output, "has_completion_function=1")
+}
+
+func TestCompleteCmdInBashScript(t *testing.T) {
+	rootCmd := &Command{Use: "root", Args: NoArgs, Run: emptyRun}
+	child := &Command{
+		Use:               "child",
+		ValidArgsFunction: validArgsFunc,
+		Run:               emptyRun,
+	}
+	rootCmd.AddCommand(child)
+
+	buf := new(bytes.Buffer)
+	assertNoErr(t, rootCmd.GenBashCompletion(buf))
+	output := buf.String()
+
+	check(t, output, ShellCompNoDescRequestCmd)
+}
+
+func TestCompleteNoDesCmdInZshScript(t *testing.T) {
+	rootCmd := &Command{Use: "root", Args: NoArgs, Run: emptyRun}
+	child := &Command{
+		Use:               "child",
+		ValidArgsFunction: validArgsFunc,
+		Run:               emptyRun,
+	}
+	rootCmd.AddCommand(child)
+
+	buf := new(bytes.Buffer)
+	assertNoErr(t, rootCmd.GenZshCompletionNoDesc(buf))
+	output := buf.String()
+
+	check(t, output, ShellCompNoDescRequestCmd)
+}
+
+func TestCompleteCmdInZshScript(t *testing.T) {
+	rootCmd := &Command{Use: "root", Args: NoArgs, Run: emptyRun}
+	child := &Command{
+		Use:               "child",
+		ValidArgsFunction: validArgsFunc,
+		Run:               emptyRun,
+	}
+	rootCmd.AddCommand(child)
+
+	buf := new(bytes.Buffer)
+	assertNoErr(t, rootCmd.GenZshCompletion(buf))
+	output := buf.String()
+
+	check(t, output, ShellCompRequestCmd)
+	checkOmit(t, output, ShellCompNoDescRequestCmd)
+}
+
+func TestFlagCompletionInGo(t *testing.T) {
+	rootCmd := &Command{
+		Use: "root",
+		Run: emptyRun,
+	}
+	rootCmd.Flags().IntP("introot", "i", -1, "help message for flag introot")
+	assertNoErr(t, rootCmd.RegisterFlagCompletionFunc("introot", func(cmd *Command, args []string, toComplete string) ([]string, ShellCompDirective) {
+		completions := []string{}
+		for _, comp := range []string{"1\tThe first", "2\tThe second", "10\tThe tenth"} {
+			if strings.HasPrefix(comp, toComplete) {
+				completions = append(completions, comp)
+			}
+		}
+		return completions, ShellCompDirectiveDefault
+	}))
+	rootCmd.Flags().String("filename", "", "Enter a filename")
+	assertNoErr(t, rootCmd.RegisterFlagCompletionFunc("filename", func(cmd *Command, args []string, toComplete string) ([]string, ShellCompDirective) {
+		completions := []string{}
+		for _, comp := range []string{"file.yaml\tYAML format", "myfile.json\tJSON format", "file.xml\tXML format"} {
+			if strings.HasPrefix(comp, toComplete) {
+				completions = append(completions, comp)
+			}
+		}
+		return completions, ShellCompDirectiveNoSpace | ShellCompDirectiveNoFileComp
+	}))
+
+	// Test completing an empty string
+	output, err := executeCommand(rootCmd, ShellCompNoDescRequestCmd, "--introot", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected := strings.Join([]string{
+		"1",
+		"2",
+		"10",
+		":0",
+		"Completion ended with directive: ShellCompDirectiveDefault", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Check completing with a prefix
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "--introot", "1")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"1",
+		"10",
+		":0",
+		"Completion ended with directive: ShellCompDirectiveDefault", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test completing an empty string
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "--filename", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"file.yaml",
+		"myfile.json",
+		"file.xml",
+		":6",
+		"Completion ended with directive: ShellCompDirectiveNoSpace, ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Check completing with a prefix
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "--filename", "f")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"file.yaml",
+		"file.xml",
+		":6",
+		"Completion ended with directive: ShellCompDirectiveNoSpace, ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+}
+
+func TestValidArgsFuncChildCmdsWithDesc(t *testing.T) {
+	rootCmd := &Command{Use: "root", Args: NoArgs, Run: emptyRun}
+	child1Cmd := &Command{
+		Use:               "child1",
+		ValidArgsFunction: validArgsFunc,
+		Run:               emptyRun,
+	}
+	child2Cmd := &Command{
+		Use:               "child2",
+		ValidArgsFunction: validArgsFunc2,
+		Run:               emptyRun,
+	}
+	rootCmd.AddCommand(child1Cmd, child2Cmd)
+
+	// Test completion of first sub-command with empty argument
+	output, err := executeCommand(rootCmd, ShellCompRequestCmd, "child1", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected := strings.Join([]string{
+		"one\tThe first",
+		"two\tThe second",
+		":0",
+		"Completion ended with directive: ShellCompDirectiveDefault", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test completion of first sub-command with a prefix to complete
+	output, err = executeCommand(rootCmd, ShellCompRequestCmd, "child1", "t")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"two\tThe second",
+		":0",
+		"Completion ended with directive: ShellCompDirectiveDefault", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Check completing with wrong number of args
+	output, err = executeCommand(rootCmd, ShellCompRequestCmd, "child1", "unexpectedArg", "t")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test completion of second sub-command with empty argument
+	output, err = executeCommand(rootCmd, ShellCompRequestCmd, "child2", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"three\tThe third",
+		"four\tThe fourth",
+		":0",
+		"Completion ended with directive: ShellCompDirectiveDefault", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	output, err = executeCommand(rootCmd, ShellCompRequestCmd, "child2", "t")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"three\tThe third",
+		":0",
+		"Completion ended with directive: ShellCompDirectiveDefault", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Check completing with wrong number of args
+	output, err = executeCommand(rootCmd, ShellCompRequestCmd, "child2", "unexpectedArg", "t")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+}
+
+func TestFlagCompletionWithNotInterspersedArgs(t *testing.T) {
+	rootCmd := &Command{Use: "root", Run: emptyRun}
+	childCmd := &Command{
+		Use: "child",
+		Run: emptyRun,
+		ValidArgsFunction: func(cmd *Command, args []string, toComplete string) ([]string, ShellCompDirective) {
+			return []string{"--validarg", "test"}, ShellCompDirectiveDefault
+		},
+	}
+	childCmd2 := &Command{
+		Use:       "child2",
+		Run:       emptyRun,
+		ValidArgs: []string{"arg1", "arg2"},
+	}
+	rootCmd.AddCommand(childCmd, childCmd2)
+	childCmd.Flags().Bool("bool", false, "test bool flag")
+	childCmd.Flags().String("string", "", "test string flag")
+	_ = childCmd.RegisterFlagCompletionFunc("string", func(cmd *Command, args []string, toComplete string) ([]string, ShellCompDirective) {
+		return []string{"myval"}, ShellCompDirectiveDefault
+	})
+
+	// Test flag completion with no argument
+	output, err := executeCommand(rootCmd, ShellCompRequestCmd, "child", "--")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected := strings.Join([]string{
+		"--bool\ttest bool flag",
+		"--help\thelp for child",
+		"--string\ttest string flag",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test that no flags are completed after the -- arg
+	output, err = executeCommand(rootCmd, ShellCompRequestCmd, "child", "--", "-")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"--validarg",
+		"test",
+		":0",
+		"Completion ended with directive: ShellCompDirectiveDefault", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test that no flags are completed after the -- arg with a flag set
+	output, err = executeCommand(rootCmd, ShellCompRequestCmd, "child", "--bool", "--", "-")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"--validarg",
+		"test",
+		":0",
+		"Completion ended with directive: ShellCompDirectiveDefault", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// set Interspersed to false which means that no flags should be completed after the first arg
+	childCmd.Flags().SetInterspersed(false)
+
+	// Test that no flags are completed after the first arg
+	output, err = executeCommand(rootCmd, ShellCompRequestCmd, "child", "arg", "--")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"--validarg",
+		"test",
+		":0",
+		"Completion ended with directive: ShellCompDirectiveDefault", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test that no flags are completed after the fist arg with a flag set
+	output, err = executeCommand(rootCmd, ShellCompRequestCmd, "child", "--string", "t", "arg", "--")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"--validarg",
+		"test",
+		":0",
+		"Completion ended with directive: ShellCompDirectiveDefault", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Check that args are still completed after --
+	output, err = executeCommand(rootCmd, ShellCompRequestCmd, "child", "--", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"--validarg",
+		"test",
+		":0",
+		"Completion ended with directive: ShellCompDirectiveDefault", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Check that args are still completed even if flagname with ValidArgsFunction exists
+	output, err = executeCommand(rootCmd, ShellCompRequestCmd, "child", "--", "--string", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"--validarg",
+		"test",
+		":0",
+		"Completion ended with directive: ShellCompDirectiveDefault", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Check that args are still completed even if flagname with ValidArgsFunction exists
+	output, err = executeCommand(rootCmd, ShellCompRequestCmd, "child2", "--", "a")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"arg1",
+		"arg2",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Check that --validarg is not parsed as flag after --
+	output, err = executeCommand(rootCmd, ShellCompRequestCmd, "child", "--", "--validarg", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"--validarg",
+		"test",
+		":0",
+		"Completion ended with directive: ShellCompDirectiveDefault", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Check that --validarg is not parsed as flag after an arg
+	output, err = executeCommand(rootCmd, ShellCompRequestCmd, "child", "arg", "--validarg", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"--validarg",
+		"test",
+		":0",
+		"Completion ended with directive: ShellCompDirectiveDefault", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Check that --validarg is added to args for the ValidArgsFunction
+	childCmd.ValidArgsFunction = func(cmd *Command, args []string, toComplete string) ([]string, ShellCompDirective) {
+		return args, ShellCompDirectiveDefault
+	}
+	output, err = executeCommand(rootCmd, ShellCompRequestCmd, "child", "--", "--validarg", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"--validarg",
+		":0",
+		"Completion ended with directive: ShellCompDirectiveDefault", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Check that --validarg is added to args for the ValidArgsFunction and toComplete is also set correctly
+	childCmd.ValidArgsFunction = func(cmd *Command, args []string, toComplete string) ([]string, ShellCompDirective) {
+		return append(args, toComplete), ShellCompDirectiveDefault
+	}
+	output, err = executeCommand(rootCmd, ShellCompRequestCmd, "child", "--", "--validarg", "--toComp=ab")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"--validarg",
+		"--toComp=ab",
+		":0",
+		"Completion ended with directive: ShellCompDirectiveDefault", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+}
+
+func TestFlagCompletionWorksRootCommandAddedAfterFlags(t *testing.T) {
+	rootCmd := &Command{Use: "root", Run: emptyRun}
+	childCmd := &Command{
+		Use: "child",
+		Run: emptyRun,
+		ValidArgsFunction: func(cmd *Command, args []string, toComplete string) ([]string, ShellCompDirective) {
+			return []string{"--validarg", "test"}, ShellCompDirectiveDefault
+		},
+	}
+	childCmd.Flags().Bool("bool", false, "test bool flag")
+	childCmd.Flags().String("string", "", "test string flag")
+	_ = childCmd.RegisterFlagCompletionFunc("string", func(cmd *Command, args []string, toComplete string) ([]string, ShellCompDirective) {
+		return []string{"myval"}, ShellCompDirectiveDefault
+	})
+
+	// Important: This is a test for https://github.com/spf13/cobra/issues/1437
+	// Only add the subcommand after RegisterFlagCompletionFunc was called, do not change this order!
+	rootCmd.AddCommand(childCmd)
+
+	// Test that flag completion works for the subcmd
+	output, err := executeCommand(rootCmd, ShellCompRequestCmd, "child", "--string", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected := strings.Join([]string{
+		"myval",
+		":0",
+		"Completion ended with directive: ShellCompDirectiveDefault", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+}
+
+func TestFlagCompletionForPersistentFlagsCalledFromSubCmd(t *testing.T) {
+	rootCmd := &Command{Use: "root", Run: emptyRun}
+	rootCmd.PersistentFlags().String("string", "", "test string flag")
+	_ = rootCmd.RegisterFlagCompletionFunc("string", func(cmd *Command, args []string, toComplete string) ([]string, ShellCompDirective) {
+		return []string{"myval"}, ShellCompDirectiveDefault
+	})
+
+	childCmd := &Command{
+		Use: "child",
+		Run: emptyRun,
+		ValidArgsFunction: func(cmd *Command, args []string, toComplete string) ([]string, ShellCompDirective) {
+			return []string{"--validarg", "test"}, ShellCompDirectiveDefault
+		},
+	}
+	childCmd.Flags().Bool("bool", false, "test bool flag")
+	rootCmd.AddCommand(childCmd)
+
+	// Test that persistent flag completion works for the subcmd
+	output, err := executeCommand(rootCmd, ShellCompRequestCmd, "child", "--string", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected := strings.Join([]string{
+		"myval",
+		":0",
+		"Completion ended with directive: ShellCompDirectiveDefault", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+}
+
+// This test tries to register flag completion concurrently to make sure the
+// code handles concurrency properly.
+// This was reported as a problem when tests are run concurrently:
+// https://github.com/spf13/cobra/issues/1320
+//
+// NOTE: this test can sometimes pass even if the code were to not handle
+// concurrency properly. This is not great but the important part is that
+// it should never fail.  Therefore, if the tests fails sometimes, we will
+// still be able to know there is a problem.
+func TestFlagCompletionConcurrentRegistration(t *testing.T) {
+	rootCmd := &Command{Use: "root", Run: emptyRun}
+	const maxFlags = 50
+	for i := 1; i < maxFlags; i += 2 {
+		flagName := fmt.Sprintf("flag%d", i)
+		rootCmd.Flags().String(flagName, "", fmt.Sprintf("test %s flag on root", flagName))
+	}
+
+	childCmd := &Command{
+		Use: "child",
+		Run: emptyRun,
+	}
+	for i := 2; i <= maxFlags; i += 2 {
+		flagName := fmt.Sprintf("flag%d", i)
+		childCmd.Flags().String(flagName, "", fmt.Sprintf("test %s flag on child", flagName))
+	}
+
+	rootCmd.AddCommand(childCmd)
+
+	// Register completion in different threads to test concurrency.
+	var wg sync.WaitGroup
+	for i := 1; i <= maxFlags; i++ {
+		index := i
+		flagName := fmt.Sprintf("flag%d", i)
+		wg.Add(1)
+		go func() {
+			defer wg.Done()
+			cmd := rootCmd
+			if index%2 == 0 {
+				cmd = childCmd
+			}
+			_ = cmd.RegisterFlagCompletionFunc(flagName, func(cmd *Command, args []string, toComplete string) ([]string, ShellCompDirective) {
+				return []string{fmt.Sprintf("flag%d", index)}, ShellCompDirectiveDefault
+			})
+		}()
+	}
+
+	wg.Wait()
+
+	// Test that flag completion works for each flag
+	for i := 1; i <= 6; i++ {
+		var output string
+		var err error
+		flagName := fmt.Sprintf("flag%d", i)
+
+		if i%2 == 1 {
+			output, err = executeCommand(rootCmd, ShellCompRequestCmd, "--"+flagName, "")
+		} else {
+			output, err = executeCommand(rootCmd, ShellCompRequestCmd, "child", "--"+flagName, "")
+		}
+
+		if err != nil {
+			t.Errorf("Unexpected error: %v", err)
+		}
+
+		expected := strings.Join([]string{
+			flagName,
+			":0",
+			"Completion ended with directive: ShellCompDirectiveDefault", ""}, "\n")
+
+		if output != expected {
+			t.Errorf("expected: %q, got: %q", expected, output)
+		}
+	}
+}
+
+func TestFlagCompletionInGoWithDesc(t *testing.T) {
+	rootCmd := &Command{
+		Use: "root",
+		Run: emptyRun,
+	}
+	rootCmd.Flags().IntP("introot", "i", -1, "help message for flag introot")
+	assertNoErr(t, rootCmd.RegisterFlagCompletionFunc("introot", func(cmd *Command, args []string, toComplete string) ([]string, ShellCompDirective) {
+		completions := []string{}
+		for _, comp := range []string{"1\tThe first", "2\tThe second", "10\tThe tenth"} {
+			if strings.HasPrefix(comp, toComplete) {
+				completions = append(completions, comp)
+			}
+		}
+		return completions, ShellCompDirectiveDefault
+	}))
+	rootCmd.Flags().String("filename", "", "Enter a filename")
+	assertNoErr(t, rootCmd.RegisterFlagCompletionFunc("filename", func(cmd *Command, args []string, toComplete string) ([]string, ShellCompDirective) {
+		completions := []string{}
+		for _, comp := range []string{"file.yaml\tYAML format", "myfile.json\tJSON format", "file.xml\tXML format"} {
+			if strings.HasPrefix(comp, toComplete) {
+				completions = append(completions, comp)
+			}
+		}
+		return completions, ShellCompDirectiveNoSpace | ShellCompDirectiveNoFileComp
+	}))
+
+	// Test completing an empty string
+	output, err := executeCommand(rootCmd, ShellCompRequestCmd, "--introot", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected := strings.Join([]string{
+		"1\tThe first",
+		"2\tThe second",
+		"10\tThe tenth",
+		":0",
+		"Completion ended with directive: ShellCompDirectiveDefault", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Check completing with a prefix
+	output, err = executeCommand(rootCmd, ShellCompRequestCmd, "--introot", "1")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"1\tThe first",
+		"10\tThe tenth",
+		":0",
+		"Completion ended with directive: ShellCompDirectiveDefault", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test completing an empty string
+	output, err = executeCommand(rootCmd, ShellCompRequestCmd, "--filename", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"file.yaml\tYAML format",
+		"myfile.json\tJSON format",
+		"file.xml\tXML format",
+		":6",
+		"Completion ended with directive: ShellCompDirectiveNoSpace, ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Check completing with a prefix
+	output, err = executeCommand(rootCmd, ShellCompRequestCmd, "--filename", "f")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"file.yaml\tYAML format",
+		"file.xml\tXML format",
+		":6",
+		"Completion ended with directive: ShellCompDirectiveNoSpace, ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+}
+
+func TestValidArgsNotValidArgsFunc(t *testing.T) {
+	rootCmd := &Command{
+		Use:       "root",
+		ValidArgs: []string{"one", "two"},
+		ValidArgsFunction: func(cmd *Command, args []string, toComplete string) ([]string, ShellCompDirective) {
+			return []string{"three", "four"}, ShellCompDirectiveNoFileComp
+		},
+		Run: emptyRun,
+	}
+
+	// Test that if both ValidArgs and ValidArgsFunction are present
+	// only ValidArgs is considered
+	output, err := executeCommand(rootCmd, ShellCompNoDescRequestCmd, "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected := strings.Join([]string{
+		"one",
+		"two",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Check completing with a prefix
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "t")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"two",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+}
+
+func TestArgAliasesCompletionInGo(t *testing.T) {
+	rootCmd := &Command{
+		Use:        "root",
+		Args:       OnlyValidArgs,
+		ValidArgs:  []string{"one", "two", "three"},
+		ArgAliases: []string{"un", "deux", "trois"},
+		Run:        emptyRun,
+	}
+
+	// Test that argaliases are not completed when there are validargs that match
+	output, err := executeCommand(rootCmd, ShellCompNoDescRequestCmd, "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected := strings.Join([]string{
+		"one",
+		"two",
+		"three",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test that argaliases are not completed when there are validargs that match using a prefix
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "t")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"two",
+		"three",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test that argaliases are completed when there are no validargs that match
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "tr")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"trois",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+}
+
+func TestCompleteHelp(t *testing.T) {
+	rootCmd := &Command{Use: "root", Args: NoArgs, Run: emptyRun}
+	child1Cmd := &Command{
+		Use: "child1",
+		Run: emptyRun,
+	}
+	child2Cmd := &Command{
+		Use: "child2",
+		Run: emptyRun,
+	}
+	rootCmd.AddCommand(child1Cmd, child2Cmd)
+
+	child3Cmd := &Command{
+		Use: "child3",
+		Run: emptyRun,
+	}
+	child1Cmd.AddCommand(child3Cmd)
+
+	// Test that completion includes the help command
+	output, err := executeCommand(rootCmd, ShellCompNoDescRequestCmd, "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected := strings.Join([]string{
+		"child1",
+		"child2",
+		"completion",
+		"help",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test sub-commands are completed on first level of help command
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "help", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"child1",
+		"child2",
+		"completion",
+		"help", // "<program> help help" is a valid command, so should be completed
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test sub-commands are completed on first level of help command
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "help", "child1", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"child3",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+}
+
+func removeCompCmd(rootCmd *Command) {
+	// Remove completion command for the next test
+	for _, cmd := range rootCmd.commands {
+		if cmd.Name() == compCmdName {
+			rootCmd.RemoveCommand(cmd)
+			return
+		}
+	}
+}
+
+func TestDefaultCompletionCmd(t *testing.T) {
+	rootCmd := &Command{
+		Use:  "root",
+		Args: NoArgs,
+		Run:  emptyRun,
+	}
+
+	// Test that no completion command is created if there are not other sub-commands
+	assertNoErr(t, rootCmd.Execute())
+	for _, cmd := range rootCmd.commands {
+		if cmd.Name() == compCmdName {
+			t.Errorf("Should not have a 'completion' command when there are no other sub-commands of root")
+			break
+		}
+	}
+
+	subCmd := &Command{
+		Use: "sub",
+		Run: emptyRun,
+	}
+	rootCmd.AddCommand(subCmd)
+
+	// Test that a completion command is created if there are other sub-commands
+	found := false
+	assertNoErr(t, rootCmd.Execute())
+	for _, cmd := range rootCmd.commands {
+		if cmd.Name() == compCmdName {
+			found = true
+			break
+		}
+	}
+	if !found {
+		t.Errorf("Should have a 'completion' command when there are other sub-commands of root")
+	}
+	// Remove completion command for the next test
+	removeCompCmd(rootCmd)
+
+	// Test that the default completion command can be disabled
+	rootCmd.CompletionOptions.DisableDefaultCmd = true
+	assertNoErr(t, rootCmd.Execute())
+	for _, cmd := range rootCmd.commands {
+		if cmd.Name() == compCmdName {
+			t.Errorf("Should not have a 'completion' command when the feature is disabled")
+			break
+		}
+	}
+	// Re-enable for next test
+	rootCmd.CompletionOptions.DisableDefaultCmd = false
+
+	// Test that completion descriptions are enabled by default
+	output, err := executeCommand(rootCmd, compCmdName, "zsh")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	check(t, output, ShellCompRequestCmd)
+	checkOmit(t, output, ShellCompNoDescRequestCmd)
+	// Remove completion command for the next test
+	removeCompCmd(rootCmd)
+
+	// Test that completion descriptions can be disabled completely
+	rootCmd.CompletionOptions.DisableDescriptions = true
+	output, err = executeCommand(rootCmd, compCmdName, "zsh")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	check(t, output, ShellCompNoDescRequestCmd)
+	// Re-enable for next test
+	rootCmd.CompletionOptions.DisableDescriptions = false
+	// Remove completion command for the next test
+	removeCompCmd(rootCmd)
+
+	var compCmd *Command
+	// Test that the --no-descriptions flag is present on all shells
+	assertNoErr(t, rootCmd.Execute())
+	for _, shell := range []string{"bash", "fish", "powershell", "zsh"} {
+		if compCmd, _, err = rootCmd.Find([]string{compCmdName, shell}); err != nil {
+			t.Errorf("Unexpected error: %v", err)
+		}
+		if flag := compCmd.Flags().Lookup(compCmdNoDescFlagName); flag == nil {
+			t.Errorf("Missing --%s flag for %s shell", compCmdNoDescFlagName, shell)
+		}
+	}
+	// Remove completion command for the next test
+	removeCompCmd(rootCmd)
+
+	// Test that the '--no-descriptions' flag can be disabled
+	rootCmd.CompletionOptions.DisableNoDescFlag = true
+	assertNoErr(t, rootCmd.Execute())
+	for _, shell := range []string{"fish", "zsh", "bash", "powershell"} {
+		if compCmd, _, err = rootCmd.Find([]string{compCmdName, shell}); err != nil {
+			t.Errorf("Unexpected error: %v", err)
+		}
+		if flag := compCmd.Flags().Lookup(compCmdNoDescFlagName); flag != nil {
+			t.Errorf("Unexpected --%s flag for %s shell", compCmdNoDescFlagName, shell)
+		}
+	}
+	// Re-enable for next test
+	rootCmd.CompletionOptions.DisableNoDescFlag = false
+	// Remove completion command for the next test
+	removeCompCmd(rootCmd)
+
+	// Test that the '--no-descriptions' flag is disabled when descriptions are disabled
+	rootCmd.CompletionOptions.DisableDescriptions = true
+	assertNoErr(t, rootCmd.Execute())
+	for _, shell := range []string{"fish", "zsh", "bash", "powershell"} {
+		if compCmd, _, err = rootCmd.Find([]string{compCmdName, shell}); err != nil {
+			t.Errorf("Unexpected error: %v", err)
+		}
+		if flag := compCmd.Flags().Lookup(compCmdNoDescFlagName); flag != nil {
+			t.Errorf("Unexpected --%s flag for %s shell", compCmdNoDescFlagName, shell)
+		}
+	}
+	// Re-enable for next test
+	rootCmd.CompletionOptions.DisableDescriptions = false
+	// Remove completion command for the next test
+	removeCompCmd(rootCmd)
+
+	// Test that the 'completion' command can be hidden
+	rootCmd.CompletionOptions.HiddenDefaultCmd = true
+	assertNoErr(t, rootCmd.Execute())
+	compCmd, _, err = rootCmd.Find([]string{compCmdName})
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+	if compCmd.Hidden == false {
+		t.Error("Default 'completion' command should be hidden but it is not")
+	}
+	// Re-enable for next test
+	rootCmd.CompletionOptions.HiddenDefaultCmd = false
+	// Remove completion command for the next test
+	removeCompCmd(rootCmd)
+}
+
+func TestCompleteCompletion(t *testing.T) {
+	rootCmd := &Command{Use: "root", Args: NoArgs, Run: emptyRun}
+	subCmd := &Command{
+		Use: "sub",
+		Run: emptyRun,
+	}
+	rootCmd.AddCommand(subCmd)
+
+	// Test sub-commands of the completion command
+	output, err := executeCommand(rootCmd, ShellCompNoDescRequestCmd, "completion", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected := strings.Join([]string{
+		"bash",
+		"fish",
+		"powershell",
+		"zsh",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test there are no completions for the sub-commands of the completion command
+	var compCmd *Command
+	for _, cmd := range rootCmd.Commands() {
+		if cmd.Name() == compCmdName {
+			compCmd = cmd
+			break
+		}
+	}
+
+	for _, shell := range compCmd.Commands() {
+		output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, compCmdName, shell.Name(), "")
+		if err != nil {
+			t.Errorf("Unexpected error: %v", err)
+		}
+
+		expected = strings.Join([]string{
+			":4",
+			"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+		if output != expected {
+			t.Errorf("expected: %q, got: %q", expected, output)
+		}
+	}
+}
+
+func TestMultipleShorthandFlagCompletion(t *testing.T) {
+	rootCmd := &Command{
+		Use:       "root",
+		ValidArgs: []string{"foo", "bar"},
+		Run:       emptyRun,
+	}
+	f := rootCmd.Flags()
+	f.BoolP("short", "s", false, "short flag 1")
+	f.BoolP("short2", "d", false, "short flag 2")
+	f.StringP("short3", "f", "", "short flag 3")
+	_ = rootCmd.RegisterFlagCompletionFunc("short3", func(*Command, []string, string) ([]string, ShellCompDirective) {
+		return []string{"works"}, ShellCompDirectiveNoFileComp
+	})
+
+	// Test that a single shorthand flag works
+	output, err := executeCommand(rootCmd, ShellCompNoDescRequestCmd, "-s", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected := strings.Join([]string{
+		"foo",
+		"bar",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test that multiple boolean shorthand flags work
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "-sd", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"foo",
+		"bar",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test that multiple boolean + string shorthand flags work
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "-sdf", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"works",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test that multiple boolean + string with equal sign shorthand flags work
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "-sdf=")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"works",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test that multiple boolean + string with equal sign with value shorthand flags work
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "-sdf=abc", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"foo",
+		"bar",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+}
+
+func TestCompleteWithDisableFlagParsing(t *testing.T) {
+
+	flagValidArgs := func(cmd *Command, args []string, toComplete string) ([]string, ShellCompDirective) {
+		return []string{"--flag", "-f"}, ShellCompDirectiveNoFileComp
+	}
+
+	rootCmd := &Command{Use: "root", Args: NoArgs, Run: emptyRun}
+	childCmd := &Command{
+		Use:                "child",
+		Run:                emptyRun,
+		DisableFlagParsing: true,
+		ValidArgsFunction:  flagValidArgs,
+	}
+	rootCmd.AddCommand(childCmd)
+
+	rootCmd.PersistentFlags().StringP("persistent", "p", "", "persistent flag")
+	childCmd.Flags().StringP("nonPersistent", "n", "", "non-persistent flag")
+
+	// Test that when DisableFlagParsing==true, ValidArgsFunction is called to complete flag names,
+	// after Cobra tried to complete the flags it knows about.
+	childCmd.DisableFlagParsing = true
+	output, err := executeCommand(rootCmd, ShellCompNoDescRequestCmd, "child", "-")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected := strings.Join([]string{
+		"--persistent",
+		"-p",
+		"--nonPersistent",
+		"-n",
+		"--flag",
+		"-f",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test that when DisableFlagParsing==false, Cobra completes the flags itself and ValidArgsFunction is not called
+	childCmd.DisableFlagParsing = false
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "child", "-")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	// Cobra was not told of any flags, so it returns nothing
+	expected = strings.Join([]string{
+		"--persistent",
+		"-p",
+		"--help",
+		"-h",
+		"--nonPersistent",
+		"-n",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+}
+
+func TestCompleteWithRootAndLegacyArgs(t *testing.T) {
+	// Test a lonely root command which uses legacyArgs().  In such a case, the root
+	// command should accept any number of arguments and completion should behave accordingly.
+	rootCmd := &Command{
+		Use:  "root",
+		Args: nil, // Args must be nil to trigger the legacyArgs() function
+		Run:  emptyRun,
+		ValidArgsFunction: func(cmd *Command, args []string, toComplete string) ([]string, ShellCompDirective) {
+			return []string{"arg1", "arg2"}, ShellCompDirectiveNoFileComp
+		},
+	}
+
+	// Make sure the first arg is completed
+	output, err := executeCommand(rootCmd, ShellCompNoDescRequestCmd, "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected := strings.Join([]string{
+		"arg1",
+		"arg2",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Make sure the completion of arguments continues
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "arg1", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"arg1",
+		"arg2",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+}
+
+func TestFixedCompletions(t *testing.T) {
+	rootCmd := &Command{Use: "root", Args: NoArgs, Run: emptyRun}
+	choices := []string{"apple", "banana", "orange"}
+	childCmd := &Command{
+		Use:               "child",
+		ValidArgsFunction: FixedCompletions(choices, ShellCompDirectiveNoFileComp),
+		Run:               emptyRun,
+	}
+	rootCmd.AddCommand(childCmd)
+
+	output, err := executeCommand(rootCmd, ShellCompNoDescRequestCmd, "child", "a")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected := strings.Join([]string{
+		"apple",
+		"banana",
+		"orange",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+}
+
+func TestCompletionForGroupedFlags(t *testing.T) {
+	getCmd := func() *Command {
+		rootCmd := &Command{
+			Use: "root",
+			Run: emptyRun,
+		}
+		childCmd := &Command{
+			Use: "child",
+			ValidArgsFunction: func(cmd *Command, args []string, toComplete string) ([]string, ShellCompDirective) {
+				return []string{"subArg"}, ShellCompDirectiveNoFileComp
+			},
+			Run: emptyRun,
+		}
+		rootCmd.AddCommand(childCmd)
+
+		rootCmd.PersistentFlags().Int("ingroup1", -1, "ingroup1")
+		rootCmd.PersistentFlags().String("ingroup2", "", "ingroup2")
+
+		childCmd.Flags().Bool("ingroup3", false, "ingroup3")
+		childCmd.Flags().Bool("nogroup", false, "nogroup")
+
+		// Add flags to a group
+		childCmd.MarkFlagsRequiredTogether("ingroup1", "ingroup2", "ingroup3")
+
+		return rootCmd
+	}
+
+	// Each test case uses a unique command from the function above.
+	testcases := []struct {
+		desc           string
+		args           []string
+		expectedOutput string
+	}{
+		{
+			desc: "flags in group not suggested without - prefix",
+			args: []string{"child", ""},
+			expectedOutput: strings.Join([]string{
+				"subArg",
+				":4",
+				"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n"),
+		},
+		{
+			desc: "flags in group suggested with - prefix",
+			args: []string{"child", "-"},
+			expectedOutput: strings.Join([]string{
+				"--ingroup1",
+				"--ingroup2",
+				"--help",
+				"-h",
+				"--ingroup3",
+				"--nogroup",
+				":4",
+				"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n"),
+		},
+		{
+			desc: "when flag in group present, other flags in group suggested even without - prefix",
+			args: []string{"child", "--ingroup2", "value", ""},
+			expectedOutput: strings.Join([]string{
+				"--ingroup1",
+				"--ingroup3",
+				"subArg",
+				":4",
+				"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n"),
+		},
+		{
+			desc: "when all flags in group present, flags not suggested without - prefix",
+			args: []string{"child", "--ingroup1", "8", "--ingroup2", "value2", "--ingroup3", ""},
+			expectedOutput: strings.Join([]string{
+				"subArg",
+				":4",
+				"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n"),
+		},
+		{
+			desc: "group ignored if some flags not applicable",
+			args: []string{"--ingroup2", "value", ""},
+			expectedOutput: strings.Join([]string{
+				"child",
+				"completion",
+				"help",
+				":4",
+				"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n"),
+		},
+	}
+
+	for _, tc := range testcases {
+		t.Run(tc.desc, func(t *testing.T) {
+			c := getCmd()
+			args := []string{ShellCompNoDescRequestCmd}
+			args = append(args, tc.args...)
+			output, err := executeCommand(c, args...)
+			switch {
+			case err == nil && output != tc.expectedOutput:
+				t.Errorf("expected: %q, got: %q", tc.expectedOutput, output)
+			case err != nil:
+				t.Errorf("Unexpected error %q", err)
+			}
+		})
+	}
+}
+
+func TestCompletionForOneRequiredGroupFlags(t *testing.T) {
+	getCmd := func() *Command {
+		rootCmd := &Command{
+			Use: "root",
+			Run: emptyRun,
+		}
+		childCmd := &Command{
+			Use: "child",
+			ValidArgsFunction: func(cmd *Command, args []string, toComplete string) ([]string, ShellCompDirective) {
+				return []string{"subArg"}, ShellCompDirectiveNoFileComp
+			},
+			Run: emptyRun,
+		}
+		rootCmd.AddCommand(childCmd)
+
+		rootCmd.PersistentFlags().Int("ingroup1", -1, "ingroup1")
+		rootCmd.PersistentFlags().String("ingroup2", "", "ingroup2")
+
+		childCmd.Flags().Bool("ingroup3", false, "ingroup3")
+		childCmd.Flags().Bool("nogroup", false, "nogroup")
+
+		// Add flags to a group
+		childCmd.MarkFlagsOneRequired("ingroup1", "ingroup2", "ingroup3")
+
+		return rootCmd
+	}
+
+	// Each test case uses a unique command from the function above.
+	testcases := []struct {
+		desc           string
+		args           []string
+		expectedOutput string
+	}{
+		{
+			desc: "flags in group suggested without - prefix",
+			args: []string{"child", ""},
+			expectedOutput: strings.Join([]string{
+				"--ingroup1",
+				"--ingroup2",
+				"--ingroup3",
+				"subArg",
+				":4",
+				"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n"),
+		},
+		{
+			desc: "flags in group suggested with - prefix",
+			args: []string{"child", "-"},
+			expectedOutput: strings.Join([]string{
+				"--ingroup1",
+				"--ingroup2",
+				"--ingroup3",
+				":4",
+				"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n"),
+		},
+		{
+			desc: "when any flag in group present, other flags in group not suggested without - prefix",
+			args: []string{"child", "--ingroup2", "value", ""},
+			expectedOutput: strings.Join([]string{
+				"subArg",
+				":4",
+				"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n"),
+		},
+		{
+			desc: "when all flags in group present, flags not suggested without - prefix",
+			args: []string{"child", "--ingroup1", "8", "--ingroup2", "value2", "--ingroup3", ""},
+			expectedOutput: strings.Join([]string{
+				"subArg",
+				":4",
+				"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n"),
+		},
+		{
+			desc: "group ignored if some flags not applicable",
+			args: []string{"--ingroup2", "value", ""},
+			expectedOutput: strings.Join([]string{
+				"child",
+				"completion",
+				"help",
+				":4",
+				"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n"),
+		},
+	}
+
+	for _, tc := range testcases {
+		t.Run(tc.desc, func(t *testing.T) {
+			c := getCmd()
+			args := []string{ShellCompNoDescRequestCmd}
+			args = append(args, tc.args...)
+			output, err := executeCommand(c, args...)
+			switch {
+			case err == nil && output != tc.expectedOutput:
+				t.Errorf("expected: %q, got: %q", tc.expectedOutput, output)
+			case err != nil:
+				t.Errorf("Unexpected error %q", err)
+			}
+		})
+	}
+}
+
+func TestCompletionForMutuallyExclusiveFlags(t *testing.T) {
+	getCmd := func() *Command {
+		rootCmd := &Command{
+			Use: "root",
+			Run: emptyRun,
+		}
+		childCmd := &Command{
+			Use: "child",
+			ValidArgsFunction: func(cmd *Command, args []string, toComplete string) ([]string, ShellCompDirective) {
+				return []string{"subArg"}, ShellCompDirectiveNoFileComp
+			},
+			Run: emptyRun,
+		}
+		rootCmd.AddCommand(childCmd)
+
+		rootCmd.PersistentFlags().IntSlice("ingroup1", []int{1}, "ingroup1")
+		rootCmd.PersistentFlags().String("ingroup2", "", "ingroup2")
+
+		childCmd.Flags().Bool("ingroup3", false, "ingroup3")
+		childCmd.Flags().Bool("nogroup", false, "nogroup")
+
+		// Add flags to a group
+		childCmd.MarkFlagsMutuallyExclusive("ingroup1", "ingroup2", "ingroup3")
+
+		return rootCmd
+	}
+
+	// Each test case uses a unique command from the function above.
+	testcases := []struct {
+		desc           string
+		args           []string
+		expectedOutput string
+	}{
+		{
+			desc: "flags in mutually exclusive group not suggested without the - prefix",
+			args: []string{"child", ""},
+			expectedOutput: strings.Join([]string{
+				"subArg",
+				":4",
+				"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n"),
+		},
+		{
+			desc: "flags in mutually exclusive group suggested with the - prefix",
+			args: []string{"child", "-"},
+			expectedOutput: strings.Join([]string{
+				"--ingroup1",
+				"--ingroup2",
+				"--help",
+				"-h",
+				"--ingroup3",
+				"--nogroup",
+				":4",
+				"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n"),
+		},
+		{
+			desc: "when flag in mutually exclusive group present, other flags in group not suggested even with the - prefix",
+			args: []string{"child", "--ingroup1", "8", "-"},
+			expectedOutput: strings.Join([]string{
+				"--ingroup1", // Should be suggested again since it is a slice
+				"--help",
+				"-h",
+				"--nogroup",
+				":4",
+				"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n"),
+		},
+		{
+			desc: "group ignored if some flags not applicable",
+			args: []string{"--ingroup1", "8", "-"},
+			expectedOutput: strings.Join([]string{
+				"--help",
+				"-h",
+				"--ingroup1",
+				"--ingroup2",
+				":4",
+				"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n"),
+		},
+	}
+
+	for _, tc := range testcases {
+		t.Run(tc.desc, func(t *testing.T) {
+			c := getCmd()
+			args := []string{ShellCompNoDescRequestCmd}
+			args = append(args, tc.args...)
+			output, err := executeCommand(c, args...)
+			switch {
+			case err == nil && output != tc.expectedOutput:
+				t.Errorf("expected: %q, got: %q", tc.expectedOutput, output)
+			case err != nil:
+				t.Errorf("Unexpected error %q", err)
+			}
+		})
+	}
+}
+
+func TestCompletionCobraFlags(t *testing.T) {
+	getCmd := func() *Command {
+		rootCmd := &Command{
+			Use:     "root",
+			Version: "1.1.1",
+			Run:     emptyRun,
+		}
+		childCmd := &Command{
+			Use:     "child",
+			Version: "1.1.1",
+			Run:     emptyRun,
+			ValidArgsFunction: func(cmd *Command, args []string, toComplete string) ([]string, ShellCompDirective) {
+				return []string{"extra"}, ShellCompDirectiveNoFileComp
+			},
+		}
+		childCmd2 := &Command{
+			Use:     "child2",
+			Version: "1.1.1",
+			Run:     emptyRun,
+			ValidArgsFunction: func(cmd *Command, args []string, toComplete string) ([]string, ShellCompDirective) {
+				return []string{"extra2"}, ShellCompDirectiveNoFileComp
+			},
+		}
+		childCmd3 := &Command{
+			Use:     "child3",
+			Version: "1.1.1",
+			Run:     emptyRun,
+			ValidArgsFunction: func(cmd *Command, args []string, toComplete string) ([]string, ShellCompDirective) {
+				return []string{"extra3"}, ShellCompDirectiveNoFileComp
+			},
+		}
+		childCmd4 := &Command{
+			Use:     "child4",
+			Version: "1.1.1",
+			Run:     emptyRun,
+			ValidArgsFunction: func(cmd *Command, args []string, toComplete string) ([]string, ShellCompDirective) {
+				return []string{"extra4"}, ShellCompDirectiveNoFileComp
+			},
+			DisableFlagParsing: true,
+		}
+		childCmd5 := &Command{
+			Use:     "child5",
+			Version: "1.1.1",
+			Run:     emptyRun,
+			ValidArgsFunction: func(cmd *Command, args []string, toComplete string) ([]string, ShellCompDirective) {
+				return []string{"extra5"}, ShellCompDirectiveNoFileComp
+			},
+			DisableFlagParsing: true,
+		}
+
+		rootCmd.AddCommand(childCmd, childCmd2, childCmd3, childCmd4, childCmd5)
+
+		_ = childCmd.Flags().Bool("bool", false, "A bool flag")
+		_ = childCmd.MarkFlagRequired("bool")
+
+		// Have a command that adds its own help and version flag
+		_ = childCmd2.Flags().BoolP("help", "h", false, "My own help")
+		_ = childCmd2.Flags().BoolP("version", "v", false, "My own version")
+
+		// Have a command that only adds its own -v flag
+		_ = childCmd3.Flags().BoolP("verbose", "v", false, "Not a version flag")
+
+		// Have a command that DisablesFlagParsing but that also adds its own help and version flags
+		_ = childCmd5.Flags().BoolP("help", "h", false, "My own help")
+		_ = childCmd5.Flags().BoolP("version", "v", false, "My own version")
+
+		return rootCmd
+	}
+
+	// Each test case uses a unique command from the function above.
+	testcases := []struct {
+		desc           string
+		args           []string
+		expectedOutput string
+	}{
+		{
+			desc: "completion of help and version flags",
+			args: []string{"-"},
+			expectedOutput: strings.Join([]string{
+				"--help",
+				"-h",
+				"--version",
+				"-v",
+				":4",
+				"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n"),
+		},
+		{
+			desc: "no completion after --help flag",
+			args: []string{"--help", ""},
+			expectedOutput: strings.Join([]string{
+				":4",
+				"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n"),
+		},
+		{
+			desc: "no completion after -h flag",
+			args: []string{"-h", ""},
+			expectedOutput: strings.Join([]string{
+				":4",
+				"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n"),
+		},
+		{
+			desc: "no completion after --version flag",
+			args: []string{"--version", ""},
+			expectedOutput: strings.Join([]string{
+				":4",
+				"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n"),
+		},
+		{
+			desc: "no completion after -v flag",
+			args: []string{"-v", ""},
+			expectedOutput: strings.Join([]string{
+				":4",
+				"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n"),
+		},
+		{
+			desc: "no completion after --help flag even with other completions",
+			args: []string{"child", "--help", ""},
+			expectedOutput: strings.Join([]string{
+				":4",
+				"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n"),
+		},
+		{
+			desc: "no completion after -h flag even with other completions",
+			args: []string{"child", "-h", ""},
+			expectedOutput: strings.Join([]string{
+				":4",
+				"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n"),
+		},
+		{
+			desc: "no completion after --version flag even with other completions",
+			args: []string{"child", "--version", ""},
+			expectedOutput: strings.Join([]string{
+				":4",
+				"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n"),
+		},
+		{
+			desc: "no completion after -v flag even with other completions",
+			args: []string{"child", "-v", ""},
+			expectedOutput: strings.Join([]string{
+				":4",
+				"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n"),
+		},
+		{
+			desc: "no completion after -v flag even with other flag completions",
+			args: []string{"child", "-v", "-"},
+			expectedOutput: strings.Join([]string{
+				":4",
+				"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n"),
+		},
+		{
+			desc: "completion after --help flag when created by program",
+			args: []string{"child2", "--help", ""},
+			expectedOutput: strings.Join([]string{
+				"extra2",
+				":4",
+				"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n"),
+		},
+		{
+			desc: "completion after -h flag when created by program",
+			args: []string{"child2", "-h", ""},
+			expectedOutput: strings.Join([]string{
+				"extra2",
+				":4",
+				"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n"),
+		},
+		{
+			desc: "completion after --version flag when created by program",
+			args: []string{"child2", "--version", ""},
+			expectedOutput: strings.Join([]string{
+				"extra2",
+				":4",
+				"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n"),
+		},
+		{
+			desc: "completion after -v flag when created by program",
+			args: []string{"child2", "-v", ""},
+			expectedOutput: strings.Join([]string{
+				"extra2",
+				":4",
+				"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n"),
+		},
+		{
+			desc: "completion after --version when only -v flag was created by program",
+			args: []string{"child3", "--version", ""},
+			expectedOutput: strings.Join([]string{
+				":4",
+				"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n"),
+		},
+		{
+			desc: "completion after -v flag when only -v flag was created by program",
+			args: []string{"child3", "-v", ""},
+			expectedOutput: strings.Join([]string{
+				"extra3",
+				":4",
+				"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n"),
+		},
+		{
+			desc: "no completion for --help/-h and --version/-v flags when DisableFlagParsing=true",
+			args: []string{"child4", "-"},
+			expectedOutput: strings.Join([]string{
+				"extra4",
+				":4",
+				"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n"),
+		},
+		{
+			desc: "completions for program-defined --help/-h and --version/-v flags even when DisableFlagParsing=true",
+			args: []string{"child5", "-"},
+			expectedOutput: strings.Join([]string{
+				"--help",
+				"-h",
+				"--version",
+				"-v",
+				"extra5",
+				":4",
+				"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n"),
+		},
+	}
+
+	for _, tc := range testcases {
+		t.Run(tc.desc, func(t *testing.T) {
+			c := getCmd()
+			args := []string{ShellCompNoDescRequestCmd}
+			args = append(args, tc.args...)
+			output, err := executeCommand(c, args...)
+			switch {
+			case err == nil && output != tc.expectedOutput:
+				t.Errorf("expected: %q, got: %q", tc.expectedOutput, output)
+			case err != nil:
+				t.Errorf("Unexpected error %q", err)
+			}
+		})
+	}
+}
+
+func TestArgsNotDetectedAsFlagsCompletionInGo(t *testing.T) {
+	// Regression test that ensures the bug described in
+	// https://github.com/spf13/cobra/issues/1816 does not occur anymore.
+
+	root := Command{
+		Use: "root",
+		ValidArgsFunction: func(cmd *Command, args []string, toComplete string) ([]string, ShellCompDirective) {
+			return []string{"service", "1-123", "11-123"}, ShellCompDirectiveNoFileComp
+		},
+	}
+
+	completion := `service
+1-123
+11-123
+:4
+Completion ended with directive: ShellCompDirectiveNoFileComp
+`
+
+	testcases := []struct {
+		desc           string
+		args           []string
+		expectedOutput string
+	}{
+		{
+			desc:           "empty",
+			args:           []string{""},
+			expectedOutput: completion,
+		},
+		{
+			desc:           "service only",
+			args:           []string{"service", ""},
+			expectedOutput: completion,
+		},
+		{
+			desc:           "service last",
+			args:           []string{"1-123", "service", ""},
+			expectedOutput: completion,
+		},
+		{
+			desc:           "two digit prefixed dash last",
+			args:           []string{"service", "11-123", ""},
+			expectedOutput: completion,
+		},
+		{
+			desc:           "one digit prefixed dash last",
+			args:           []string{"service", "1-123", ""},
+			expectedOutput: completion,
+		},
+	}
+	for _, tc := range testcases {
+		t.Run(tc.desc, func(t *testing.T) {
+			args := []string{ShellCompNoDescRequestCmd}
+			args = append(args, tc.args...)
+			output, err := executeCommand(&root, args...)
+			switch {
+			case err == nil && output != tc.expectedOutput:
+				t.Errorf("expected: %q, got: %q", tc.expectedOutput, output)
+			case err != nil:
+				t.Errorf("Unexpected error %q", err)
+			}
+		})
+	}
+}
+
+func TestGetFlagCompletion(t *testing.T) {
+	rootCmd := &Command{Use: "root", Run: emptyRun}
+
+	rootCmd.Flags().String("rootflag", "", "root flag")
+	_ = rootCmd.RegisterFlagCompletionFunc("rootflag", func(cmd *Command, args []string, toComplete string) ([]string, ShellCompDirective) {
+		return []string{"rootvalue"}, ShellCompDirectiveKeepOrder
+	})
+
+	rootCmd.PersistentFlags().String("persistentflag", "", "persistent flag")
+	_ = rootCmd.RegisterFlagCompletionFunc("persistentflag", func(cmd *Command, args []string, toComplete string) ([]string, ShellCompDirective) {
+		return []string{"persistentvalue"}, ShellCompDirectiveDefault
+	})
+
+	childCmd := &Command{Use: "child", Run: emptyRun}
+
+	childCmd.Flags().String("childflag", "", "child flag")
+	_ = childCmd.RegisterFlagCompletionFunc("childflag", func(cmd *Command, args []string, toComplete string) ([]string, ShellCompDirective) {
+		return []string{"childvalue"}, ShellCompDirectiveNoFileComp | ShellCompDirectiveNoSpace
+	})
+
+	rootCmd.AddCommand(childCmd)
+
+	testcases := []struct {
+		desc      string
+		cmd       *Command
+		flagName  string
+		exists    bool
+		comps     []string
+		directive ShellCompDirective
+	}{
+		{
+			desc:      "get flag completion function for command",
+			cmd:       rootCmd,
+			flagName:  "rootflag",
+			exists:    true,
+			comps:     []string{"rootvalue"},
+			directive: ShellCompDirectiveKeepOrder,
+		},
+		{
+			desc:      "get persistent flag completion function for command",
+			cmd:       rootCmd,
+			flagName:  "persistentflag",
+			exists:    true,
+			comps:     []string{"persistentvalue"},
+			directive: ShellCompDirectiveDefault,
+		},
+		{
+			desc:      "get flag completion function for child command",
+			cmd:       childCmd,
+			flagName:  "childflag",
+			exists:    true,
+			comps:     []string{"childvalue"},
+			directive: ShellCompDirectiveNoFileComp | ShellCompDirectiveNoSpace,
+		},
+		{
+			desc:      "get persistent flag completion function for child command",
+			cmd:       childCmd,
+			flagName:  "persistentflag",
+			exists:    true,
+			comps:     []string{"persistentvalue"},
+			directive: ShellCompDirectiveDefault,
+		},
+		{
+			desc:     "cannot get flag completion function for local parent flag",
+			cmd:      childCmd,
+			flagName: "rootflag",
+			exists:   false,
+		},
+	}
+
+	for _, tc := range testcases {
+		t.Run(tc.desc, func(t *testing.T) {
+			compFunc, exists := tc.cmd.GetFlagCompletionFunc(tc.flagName)
+			if tc.exists != exists {
+				t.Errorf("Unexpected result looking for flag completion function")
+			}
+
+			if exists {
+				comps, directive := compFunc(tc.cmd, []string{}, "")
+				if strings.Join(tc.comps, " ") != strings.Join(comps, " ") {
+					t.Errorf("Unexpected completions %q", comps)
+				}
+				if tc.directive != directive {
+					t.Errorf("Unexpected directive %q", directive)
+				}
+			}
+		})
+	}
+}