initial commit

vendor/github.com/spf13/pflag/flag_test.go

@@ -0,0 +1,913 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package pflag
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"net"
+	"os"
+	"reflect"
+	"sort"
+	"strings"
+	"testing"
+	"time"
+)
+
+var (
+	testBool                     = Bool("test_bool", false, "bool value")
+	testInt                      = Int("test_int", 0, "int value")
+	testInt64                    = Int64("test_int64", 0, "int64 value")
+	testUint                     = Uint("test_uint", 0, "uint value")
+	testUint64                   = Uint64("test_uint64", 0, "uint64 value")
+	testString                   = String("test_string", "0", "string value")
+	testFloat                    = Float64("test_float64", 0, "float64 value")
+	testDuration                 = Duration("test_duration", 0, "time.Duration value")
+	testOptionalInt              = Int("test_optional_int", 0, "optional int value")
+	normalizeFlagNameInvocations = 0
+)
+
+func boolString(s string) string {
+	if s == "0" {
+		return "false"
+	}
+	return "true"
+}
+
+func TestEverything(t *testing.T) {
+	m := make(map[string]*Flag)
+	desired := "0"
+	visitor := func(f *Flag) {
+		if len(f.Name) > 5 && f.Name[0:5] == "test_" {
+			m[f.Name] = f
+			ok := false
+			switch {
+			case f.Value.String() == desired:
+				ok = true
+			case f.Name == "test_bool" && f.Value.String() == boolString(desired):
+				ok = true
+			case f.Name == "test_duration" && f.Value.String() == desired+"s":
+				ok = true
+			}
+			if !ok {
+				t.Error("Visit: bad value", f.Value.String(), "for", f.Name)
+			}
+		}
+	}
+	VisitAll(visitor)
+	if len(m) != 9 {
+		t.Error("VisitAll misses some flags")
+		for k, v := range m {
+			t.Log(k, *v)
+		}
+	}
+	m = make(map[string]*Flag)
+	Visit(visitor)
+	if len(m) != 0 {
+		t.Errorf("Visit sees unset flags")
+		for k, v := range m {
+			t.Log(k, *v)
+		}
+	}
+	// Now set all flags
+	Set("test_bool", "true")
+	Set("test_int", "1")
+	Set("test_int64", "1")
+	Set("test_uint", "1")
+	Set("test_uint64", "1")
+	Set("test_string", "1")
+	Set("test_float64", "1")
+	Set("test_duration", "1s")
+	Set("test_optional_int", "1")
+	desired = "1"
+	Visit(visitor)
+	if len(m) != 9 {
+		t.Error("Visit fails after set")
+		for k, v := range m {
+			t.Log(k, *v)
+		}
+	}
+	// Now test they're visited in sort order.
+	var flagNames []string
+	Visit(func(f *Flag) { flagNames = append(flagNames, f.Name) })
+	if !sort.StringsAreSorted(flagNames) {
+		t.Errorf("flag names not sorted: %v", flagNames)
+	}
+}
+
+func TestUsage(t *testing.T) {
+	called := false
+	ResetForTesting(func() { called = true })
+	if GetCommandLine().Parse([]string{"--x"}) == nil {
+		t.Error("parse did not fail for unknown flag")
+	}
+	if !called {
+		t.Error("did not call Usage for unknown flag")
+	}
+}
+
+func TestAddFlagSet(t *testing.T) {
+	oldSet := NewFlagSet("old", ContinueOnError)
+	newSet := NewFlagSet("new", ContinueOnError)
+
+	oldSet.String("flag1", "flag1", "flag1")
+	oldSet.String("flag2", "flag2", "flag2")
+
+	newSet.String("flag2", "flag2", "flag2")
+	newSet.String("flag3", "flag3", "flag3")
+
+	oldSet.AddFlagSet(newSet)
+
+	if len(oldSet.formal) != 3 {
+		t.Errorf("Unexpected result adding a FlagSet to a FlagSet %v", oldSet)
+	}
+}
+
+func TestAnnotation(t *testing.T) {
+	f := NewFlagSet("shorthand", ContinueOnError)
+
+	if err := f.SetAnnotation("missing-flag", "key", nil); err == nil {
+		t.Errorf("Expected error setting annotation on non-existent flag")
+	}
+
+	f.StringP("stringa", "a", "", "string value")
+	if err := f.SetAnnotation("stringa", "key", nil); err != nil {
+		t.Errorf("Unexpected error setting new nil annotation: %v", err)
+	}
+	if annotation := f.Lookup("stringa").Annotations["key"]; annotation != nil {
+		t.Errorf("Unexpected annotation: %v", annotation)
+	}
+
+	f.StringP("stringb", "b", "", "string2 value")
+	if err := f.SetAnnotation("stringb", "key", []string{"value1"}); err != nil {
+		t.Errorf("Unexpected error setting new annotation: %v", err)
+	}
+	if annotation := f.Lookup("stringb").Annotations["key"]; !reflect.DeepEqual(annotation, []string{"value1"}) {
+		t.Errorf("Unexpected annotation: %v", annotation)
+	}
+
+	if err := f.SetAnnotation("stringb", "key", []string{"value2"}); err != nil {
+		t.Errorf("Unexpected error updating annotation: %v", err)
+	}
+	if annotation := f.Lookup("stringb").Annotations["key"]; !reflect.DeepEqual(annotation, []string{"value2"}) {
+		t.Errorf("Unexpected annotation: %v", annotation)
+	}
+}
+
+func testParse(f *FlagSet, t *testing.T) {
+	if f.Parsed() {
+		t.Error("f.Parse() = true before Parse")
+	}
+	boolFlag := f.Bool("bool", false, "bool value")
+	bool2Flag := f.Bool("bool2", false, "bool2 value")
+	bool3Flag := f.Bool("bool3", false, "bool3 value")
+	intFlag := f.Int("int", 0, "int value")
+	int8Flag := f.Int8("int8", 0, "int value")
+	int32Flag := f.Int32("int32", 0, "int value")
+	int64Flag := f.Int64("int64", 0, "int64 value")
+	uintFlag := f.Uint("uint", 0, "uint value")
+	uint8Flag := f.Uint8("uint8", 0, "uint value")
+	uint16Flag := f.Uint16("uint16", 0, "uint value")
+	uint32Flag := f.Uint32("uint32", 0, "uint value")
+	uint64Flag := f.Uint64("uint64", 0, "uint64 value")
+	stringFlag := f.String("string", "0", "string value")
+	float32Flag := f.Float32("float32", 0, "float32 value")
+	float64Flag := f.Float64("float64", 0, "float64 value")
+	ipFlag := f.IP("ip", net.ParseIP("127.0.0.1"), "ip value")
+	maskFlag := f.IPMask("mask", ParseIPv4Mask("0.0.0.0"), "mask value")
+	durationFlag := f.Duration("duration", 5*time.Second, "time.Duration value")
+	optionalIntNoValueFlag := f.Int("optional-int-no-value", 0, "int value")
+	f.Lookup("optional-int-no-value").NoOptDefVal = "9"
+	optionalIntWithValueFlag := f.Int("optional-int-with-value", 0, "int value")
+	f.Lookup("optional-int-no-value").NoOptDefVal = "9"
+	extra := "one-extra-argument"
+	args := []string{
+		"--bool",
+		"--bool2=true",
+		"--bool3=false",
+		"--int=22",
+		"--int8=-8",
+		"--int32=-32",
+		"--int64=0x23",
+		"--uint", "24",
+		"--uint8=8",
+		"--uint16=16",
+		"--uint32=32",
+		"--uint64=25",
+		"--string=hello",
+		"--float32=-172e12",
+		"--float64=2718e28",
+		"--ip=10.11.12.13",
+		"--mask=255.255.255.0",
+		"--duration=2m",
+		"--optional-int-no-value",
+		"--optional-int-with-value=42",
+		extra,
+	}
+	if err := f.Parse(args); err != nil {
+		t.Fatal(err)
+	}
+	if !f.Parsed() {
+		t.Error("f.Parse() = false after Parse")
+	}
+	if *boolFlag != true {
+		t.Error("bool flag should be true, is ", *boolFlag)
+	}
+	if v, err := f.GetBool("bool"); err != nil || v != *boolFlag {
+		t.Error("GetBool does not work.")
+	}
+	if *bool2Flag != true {
+		t.Error("bool2 flag should be true, is ", *bool2Flag)
+	}
+	if *bool3Flag != false {
+		t.Error("bool3 flag should be false, is ", *bool2Flag)
+	}
+	if *intFlag != 22 {
+		t.Error("int flag should be 22, is ", *intFlag)
+	}
+	if v, err := f.GetInt("int"); err != nil || v != *intFlag {
+		t.Error("GetInt does not work.")
+	}
+	if *int8Flag != -8 {
+		t.Error("int8 flag should be 0x23, is ", *int8Flag)
+	}
+	if v, err := f.GetInt8("int8"); err != nil || v != *int8Flag {
+		t.Error("GetInt8 does not work.")
+	}
+	if *int32Flag != -32 {
+		t.Error("int32 flag should be 0x23, is ", *int32Flag)
+	}
+	if v, err := f.GetInt32("int32"); err != nil || v != *int32Flag {
+		t.Error("GetInt32 does not work.")
+	}
+	if *int64Flag != 0x23 {
+		t.Error("int64 flag should be 0x23, is ", *int64Flag)
+	}
+	if v, err := f.GetInt64("int64"); err != nil || v != *int64Flag {
+		t.Error("GetInt64 does not work.")
+	}
+	if *uintFlag != 24 {
+		t.Error("uint flag should be 24, is ", *uintFlag)
+	}
+	if v, err := f.GetUint("uint"); err != nil || v != *uintFlag {
+		t.Error("GetUint does not work.")
+	}
+	if *uint8Flag != 8 {
+		t.Error("uint8 flag should be 8, is ", *uint8Flag)
+	}
+	if v, err := f.GetUint8("uint8"); err != nil || v != *uint8Flag {
+		t.Error("GetUint8 does not work.")
+	}
+	if *uint16Flag != 16 {
+		t.Error("uint16 flag should be 16, is ", *uint16Flag)
+	}
+	if v, err := f.GetUint16("uint16"); err != nil || v != *uint16Flag {
+		t.Error("GetUint16 does not work.")
+	}
+	if *uint32Flag != 32 {
+		t.Error("uint32 flag should be 32, is ", *uint32Flag)
+	}
+	if v, err := f.GetUint32("uint32"); err != nil || v != *uint32Flag {
+		t.Error("GetUint32 does not work.")
+	}
+	if *uint64Flag != 25 {
+		t.Error("uint64 flag should be 25, is ", *uint64Flag)
+	}
+	if v, err := f.GetUint64("uint64"); err != nil || v != *uint64Flag {
+		t.Error("GetUint64 does not work.")
+	}
+	if *stringFlag != "hello" {
+		t.Error("string flag should be `hello`, is ", *stringFlag)
+	}
+	if v, err := f.GetString("string"); err != nil || v != *stringFlag {
+		t.Error("GetString does not work.")
+	}
+	if *float32Flag != -172e12 {
+		t.Error("float32 flag should be -172e12, is ", *float32Flag)
+	}
+	if v, err := f.GetFloat32("float32"); err != nil || v != *float32Flag {
+		t.Errorf("GetFloat32 returned %v but float32Flag was %v", v, *float32Flag)
+	}
+	if *float64Flag != 2718e28 {
+		t.Error("float64 flag should be 2718e28, is ", *float64Flag)
+	}
+	if v, err := f.GetFloat64("float64"); err != nil || v != *float64Flag {
+		t.Errorf("GetFloat64 returned %v but float64Flag was %v", v, *float64Flag)
+	}
+	if !(*ipFlag).Equal(net.ParseIP("10.11.12.13")) {
+		t.Error("ip flag should be 10.11.12.13, is ", *ipFlag)
+	}
+	if v, err := f.GetIP("ip"); err != nil || !v.Equal(*ipFlag) {
+		t.Errorf("GetIP returned %v but ipFlag was %v", v, *ipFlag)
+	}
+	if (*maskFlag).String() != ParseIPv4Mask("255.255.255.0").String() {
+		t.Error("mask flag should be 255.255.255.0, is ", (*maskFlag).String())
+	}
+	if v, err := f.GetIPv4Mask("mask"); err != nil || v.String() != (*maskFlag).String() {
+		t.Errorf("GetIP returned %v maskFlag was %v error was %v", v, *maskFlag, err)
+	}
+	if *durationFlag != 2*time.Minute {
+		t.Error("duration flag should be 2m, is ", *durationFlag)
+	}
+	if v, err := f.GetDuration("duration"); err != nil || v != *durationFlag {
+		t.Error("GetDuration does not work.")
+	}
+	if _, err := f.GetInt("duration"); err == nil {
+		t.Error("GetInt parsed a time.Duration?!?!")
+	}
+	if *optionalIntNoValueFlag != 9 {
+		t.Error("optional int flag should be the default value, is ", *optionalIntNoValueFlag)
+	}
+	if *optionalIntWithValueFlag != 42 {
+		t.Error("optional int flag should be 42, is ", *optionalIntWithValueFlag)
+	}
+	if len(f.Args()) != 1 {
+		t.Error("expected one argument, got", len(f.Args()))
+	} else if f.Args()[0] != extra {
+		t.Errorf("expected argument %q got %q", extra, f.Args()[0])
+	}
+}
+
+func TestShorthand(t *testing.T) {
+	f := NewFlagSet("shorthand", ContinueOnError)
+	if f.Parsed() {
+		t.Error("f.Parse() = true before Parse")
+	}
+	boolaFlag := f.BoolP("boola", "a", false, "bool value")
+	boolbFlag := f.BoolP("boolb", "b", false, "bool2 value")
+	boolcFlag := f.BoolP("boolc", "c", false, "bool3 value")
+	booldFlag := f.BoolP("boold", "d", false, "bool4 value")
+	stringaFlag := f.StringP("stringa", "s", "0", "string value")
+	stringzFlag := f.StringP("stringz", "z", "0", "string value")
+	extra := "interspersed-argument"
+	notaflag := "--i-look-like-a-flag"
+	args := []string{
+		"-ab",
+		extra,
+		"-cs",
+		"hello",
+		"-z=something",
+		"-d=true",
+		"--",
+		notaflag,
+	}
+	f.SetOutput(ioutil.Discard)
+	if err := f.Parse(args); err != nil {
+		t.Error("expected no error, got ", err)
+	}
+	if !f.Parsed() {
+		t.Error("f.Parse() = false after Parse")
+	}
+	if *boolaFlag != true {
+		t.Error("boola flag should be true, is ", *boolaFlag)
+	}
+	if *boolbFlag != true {
+		t.Error("boolb flag should be true, is ", *boolbFlag)
+	}
+	if *boolcFlag != true {
+		t.Error("boolc flag should be true, is ", *boolcFlag)
+	}
+	if *booldFlag != true {
+		t.Error("boold flag should be true, is ", *booldFlag)
+	}
+	if *stringaFlag != "hello" {
+		t.Error("stringa flag should be `hello`, is ", *stringaFlag)
+	}
+	if *stringzFlag != "something" {
+		t.Error("stringz flag should be `something`, is ", *stringzFlag)
+	}
+	if len(f.Args()) != 2 {
+		t.Error("expected one argument, got", len(f.Args()))
+	} else if f.Args()[0] != extra {
+		t.Errorf("expected argument %q got %q", extra, f.Args()[0])
+	} else if f.Args()[1] != notaflag {
+		t.Errorf("expected argument %q got %q", notaflag, f.Args()[1])
+	}
+	if f.ArgsLenAtDash() != 1 {
+		t.Errorf("expected argsLenAtDash %d got %d", f.ArgsLenAtDash(), 1)
+	}
+}
+
+func TestParse(t *testing.T) {
+	ResetForTesting(func() { t.Error("bad parse") })
+	testParse(GetCommandLine(), t)
+}
+
+func TestFlagSetParse(t *testing.T) {
+	testParse(NewFlagSet("test", ContinueOnError), t)
+}
+
+func TestChangedHelper(t *testing.T) {
+	f := NewFlagSet("changedtest", ContinueOnError)
+	_ = f.Bool("changed", false, "changed bool")
+	_ = f.Bool("settrue", true, "true to true")
+	_ = f.Bool("setfalse", false, "false to false")
+	_ = f.Bool("unchanged", false, "unchanged bool")
+
+	args := []string{"--changed", "--settrue", "--setfalse=false"}
+	if err := f.Parse(args); err != nil {
+		t.Error("f.Parse() = false after Parse")
+	}
+	if !f.Changed("changed") {
+		t.Errorf("--changed wasn't changed!")
+	}
+	if !f.Changed("settrue") {
+		t.Errorf("--settrue wasn't changed!")
+	}
+	if !f.Changed("setfalse") {
+		t.Errorf("--setfalse wasn't changed!")
+	}
+	if f.Changed("unchanged") {
+		t.Errorf("--unchanged was changed!")
+	}
+	if f.Changed("invalid") {
+		t.Errorf("--invalid was changed!")
+	}
+	if f.ArgsLenAtDash() != -1 {
+		t.Errorf("Expected argsLenAtDash: %d but got %d", -1, f.ArgsLenAtDash())
+	}
+}
+
+func replaceSeparators(name string, from []string, to string) string {
+	result := name
+	for _, sep := range from {
+		result = strings.Replace(result, sep, to, -1)
+	}
+	// Type convert to indicate normalization has been done.
+	return result
+}
+
+func wordSepNormalizeFunc(f *FlagSet, name string) NormalizedName {
+	seps := []string{"-", "_"}
+	name = replaceSeparators(name, seps, ".")
+	normalizeFlagNameInvocations++
+
+	return NormalizedName(name)
+}
+
+func testWordSepNormalizedNames(args []string, t *testing.T) {
+	f := NewFlagSet("normalized", ContinueOnError)
+	if f.Parsed() {
+		t.Error("f.Parse() = true before Parse")
+	}
+	withDashFlag := f.Bool("with-dash-flag", false, "bool value")
+	// Set this after some flags have been added and before others.
+	f.SetNormalizeFunc(wordSepNormalizeFunc)
+	withUnderFlag := f.Bool("with_under_flag", false, "bool value")
+	withBothFlag := f.Bool("with-both_flag", false, "bool value")
+	if err := f.Parse(args); err != nil {
+		t.Fatal(err)
+	}
+	if !f.Parsed() {
+		t.Error("f.Parse() = false after Parse")
+	}
+	if *withDashFlag != true {
+		t.Error("withDashFlag flag should be true, is ", *withDashFlag)
+	}
+	if *withUnderFlag != true {
+		t.Error("withUnderFlag flag should be true, is ", *withUnderFlag)
+	}
+	if *withBothFlag != true {
+		t.Error("withBothFlag flag should be true, is ", *withBothFlag)
+	}
+}
+
+func TestWordSepNormalizedNames(t *testing.T) {
+	args := []string{
+		"--with-dash-flag",
+		"--with-under-flag",
+		"--with-both-flag",
+	}
+	testWordSepNormalizedNames(args, t)
+
+	args = []string{
+		"--with_dash_flag",
+		"--with_under_flag",
+		"--with_both_flag",
+	}
+	testWordSepNormalizedNames(args, t)
+
+	args = []string{
+		"--with-dash_flag",
+		"--with-under_flag",
+		"--with-both_flag",
+	}
+	testWordSepNormalizedNames(args, t)
+}
+
+func aliasAndWordSepFlagNames(f *FlagSet, name string) NormalizedName {
+	seps := []string{"-", "_"}
+
+	oldName := replaceSeparators("old-valid_flag", seps, ".")
+	newName := replaceSeparators("valid-flag", seps, ".")
+
+	name = replaceSeparators(name, seps, ".")
+	switch name {
+	case oldName:
+		name = newName
+		break
+	}
+
+	return NormalizedName(name)
+}
+
+func TestCustomNormalizedNames(t *testing.T) {
+	f := NewFlagSet("normalized", ContinueOnError)
+	if f.Parsed() {
+		t.Error("f.Parse() = true before Parse")
+	}
+
+	validFlag := f.Bool("valid-flag", false, "bool value")
+	f.SetNormalizeFunc(aliasAndWordSepFlagNames)
+	someOtherFlag := f.Bool("some-other-flag", false, "bool value")
+
+	args := []string{"--old_valid_flag", "--some-other_flag"}
+	if err := f.Parse(args); err != nil {
+		t.Fatal(err)
+	}
+
+	if *validFlag != true {
+		t.Errorf("validFlag is %v even though we set the alias --old_valid_falg", *validFlag)
+	}
+	if *someOtherFlag != true {
+		t.Error("someOtherFlag should be true, is ", *someOtherFlag)
+	}
+}
+
+// Every flag we add, the name (displayed also in usage) should normalized
+func TestNormalizationFuncShouldChangeFlagName(t *testing.T) {
+	// Test normalization after addition
+	f := NewFlagSet("normalized", ContinueOnError)
+
+	f.Bool("valid_flag", false, "bool value")
+	if f.Lookup("valid_flag").Name != "valid_flag" {
+		t.Error("The new flag should have the name 'valid_flag' instead of ", f.Lookup("valid_flag").Name)
+	}
+
+	f.SetNormalizeFunc(wordSepNormalizeFunc)
+	if f.Lookup("valid_flag").Name != "valid.flag" {
+		t.Error("The new flag should have the name 'valid.flag' instead of ", f.Lookup("valid_flag").Name)
+	}
+
+	// Test normalization before addition
+	f = NewFlagSet("normalized", ContinueOnError)
+	f.SetNormalizeFunc(wordSepNormalizeFunc)
+
+	f.Bool("valid_flag", false, "bool value")
+	if f.Lookup("valid_flag").Name != "valid.flag" {
+		t.Error("The new flag should have the name 'valid.flag' instead of ", f.Lookup("valid_flag").Name)
+	}
+}
+
+// Declare a user-defined flag type.
+type flagVar []string
+
+func (f *flagVar) String() string {
+	return fmt.Sprint([]string(*f))
+}
+
+func (f *flagVar) Set(value string) error {
+	*f = append(*f, value)
+	return nil
+}
+
+func (f *flagVar) Type() string {
+	return "flagVar"
+}
+
+func TestUserDefined(t *testing.T) {
+	var flags FlagSet
+	flags.Init("test", ContinueOnError)
+	var v flagVar
+	flags.VarP(&v, "v", "v", "usage")
+	if err := flags.Parse([]string{"--v=1", "-v2", "-v", "3"}); err != nil {
+		t.Error(err)
+	}
+	if len(v) != 3 {
+		t.Fatal("expected 3 args; got ", len(v))
+	}
+	expect := "[1 2 3]"
+	if v.String() != expect {
+		t.Errorf("expected value %q got %q", expect, v.String())
+	}
+}
+
+func TestSetOutput(t *testing.T) {
+	var flags FlagSet
+	var buf bytes.Buffer
+	flags.SetOutput(&buf)
+	flags.Init("test", ContinueOnError)
+	flags.Parse([]string{"--unknown"})
+	if out := buf.String(); !strings.Contains(out, "--unknown") {
+		t.Logf("expected output mentioning unknown; got %q", out)
+	}
+}
+
+// This tests that one can reset the flags. This still works but not well, and is
+// superseded by FlagSet.
+func TestChangingArgs(t *testing.T) {
+	ResetForTesting(func() { t.Fatal("bad parse") })
+	oldArgs := os.Args
+	defer func() { os.Args = oldArgs }()
+	os.Args = []string{"cmd", "--before", "subcmd"}
+	before := Bool("before", false, "")
+	if err := GetCommandLine().Parse(os.Args[1:]); err != nil {
+		t.Fatal(err)
+	}
+	cmd := Arg(0)
+	os.Args = []string{"subcmd", "--after", "args"}
+	after := Bool("after", false, "")
+	Parse()
+	args := Args()
+
+	if !*before || cmd != "subcmd" || !*after || len(args) != 1 || args[0] != "args" {
+		t.Fatalf("expected true subcmd true [args] got %v %v %v %v", *before, cmd, *after, args)
+	}
+}
+
+// Test that -help invokes the usage message and returns ErrHelp.
+func TestHelp(t *testing.T) {
+	var helpCalled = false
+	fs := NewFlagSet("help test", ContinueOnError)
+	fs.Usage = func() { helpCalled = true }
+	var flag bool
+	fs.BoolVar(&flag, "flag", false, "regular flag")
+	// Regular flag invocation should work
+	err := fs.Parse([]string{"--flag=true"})
+	if err != nil {
+		t.Fatal("expected no error; got ", err)
+	}
+	if !flag {
+		t.Error("flag was not set by --flag")
+	}
+	if helpCalled {
+		t.Error("help called for regular flag")
+		helpCalled = false // reset for next test
+	}
+	// Help flag should work as expected.
+	err = fs.Parse([]string{"--help"})
+	if err == nil {
+		t.Fatal("error expected")
+	}
+	if err != ErrHelp {
+		t.Fatal("expected ErrHelp; got ", err)
+	}
+	if !helpCalled {
+		t.Fatal("help was not called")
+	}
+	// If we define a help flag, that should override.
+	var help bool
+	fs.BoolVar(&help, "help", false, "help flag")
+	helpCalled = false
+	err = fs.Parse([]string{"--help"})
+	if err != nil {
+		t.Fatal("expected no error for defined --help; got ", err)
+	}
+	if helpCalled {
+		t.Fatal("help was called; should not have been for defined help flag")
+	}
+}
+
+func TestNoInterspersed(t *testing.T) {
+	f := NewFlagSet("test", ContinueOnError)
+	f.SetInterspersed(false)
+	f.Bool("true", true, "always true")
+	f.Bool("false", false, "always false")
+	err := f.Parse([]string{"--true", "break", "--false"})
+	if err != nil {
+		t.Fatal("expected no error; got ", err)
+	}
+	args := f.Args()
+	if len(args) != 2 || args[0] != "break" || args[1] != "--false" {
+		t.Fatal("expected interspersed options/non-options to fail")
+	}
+}
+
+func TestTermination(t *testing.T) {
+	f := NewFlagSet("termination", ContinueOnError)
+	boolFlag := f.BoolP("bool", "l", false, "bool value")
+	if f.Parsed() {
+		t.Error("f.Parse() = true before Parse")
+	}
+	arg1 := "ls"
+	arg2 := "-l"
+	args := []string{
+		"--",
+		arg1,
+		arg2,
+	}
+	f.SetOutput(ioutil.Discard)
+	if err := f.Parse(args); err != nil {
+		t.Fatal("expected no error; got ", err)
+	}
+	if !f.Parsed() {
+		t.Error("f.Parse() = false after Parse")
+	}
+	if *boolFlag {
+		t.Error("expected boolFlag=false, got true")
+	}
+	if len(f.Args()) != 2 {
+		t.Errorf("expected 2 arguments, got %d: %v", len(f.Args()), f.Args())
+	}
+	if f.Args()[0] != arg1 {
+		t.Errorf("expected argument %q got %q", arg1, f.Args()[0])
+	}
+	if f.Args()[1] != arg2 {
+		t.Errorf("expected argument %q got %q", arg2, f.Args()[1])
+	}
+	if f.ArgsLenAtDash() != 0 {
+		t.Errorf("expected argsLenAtDash %d got %d", 0, f.ArgsLenAtDash())
+	}
+}
+
+func TestDeprecatedFlagInDocs(t *testing.T) {
+	f := NewFlagSet("bob", ContinueOnError)
+	f.Bool("badflag", true, "always true")
+	f.MarkDeprecated("badflag", "use --good-flag instead")
+
+	out := new(bytes.Buffer)
+	f.SetOutput(out)
+	f.PrintDefaults()
+
+	if strings.Contains(out.String(), "badflag") {
+		t.Errorf("found deprecated flag in usage!")
+	}
+}
+
+func TestDeprecatedFlagShorthandInDocs(t *testing.T) {
+	f := NewFlagSet("bob", ContinueOnError)
+	name := "noshorthandflag"
+	f.BoolP(name, "n", true, "always true")
+	f.MarkShorthandDeprecated("noshorthandflag", fmt.Sprintf("use --%s instead", name))
+
+	out := new(bytes.Buffer)
+	f.SetOutput(out)
+	f.PrintDefaults()
+
+	if strings.Contains(out.String(), "-n,") {
+		t.Errorf("found deprecated flag shorthand in usage!")
+	}
+}
+
+func parseReturnStderr(t *testing.T, f *FlagSet, args []string) (string, error) {
+	oldStderr := os.Stderr
+	r, w, _ := os.Pipe()
+	os.Stderr = w
+
+	err := f.Parse(args)
+
+	outC := make(chan string)
+	// copy the output in a separate goroutine so printing can't block indefinitely
+	go func() {
+		var buf bytes.Buffer
+		io.Copy(&buf, r)
+		outC <- buf.String()
+	}()
+
+	w.Close()
+	os.Stderr = oldStderr
+	out := <-outC
+
+	return out, err
+}
+
+func TestDeprecatedFlagUsage(t *testing.T) {
+	f := NewFlagSet("bob", ContinueOnError)
+	f.Bool("badflag", true, "always true")
+	usageMsg := "use --good-flag instead"
+	f.MarkDeprecated("badflag", usageMsg)
+
+	args := []string{"--badflag"}
+	out, err := parseReturnStderr(t, f, args)
+	if err != nil {
+		t.Fatal("expected no error; got ", err)
+	}
+
+	if !strings.Contains(out, usageMsg) {
+		t.Errorf("usageMsg not printed when using a deprecated flag!")
+	}
+}
+
+func TestDeprecatedFlagShorthandUsage(t *testing.T) {
+	f := NewFlagSet("bob", ContinueOnError)
+	name := "noshorthandflag"
+	f.BoolP(name, "n", true, "always true")
+	usageMsg := fmt.Sprintf("use --%s instead", name)
+	f.MarkShorthandDeprecated(name, usageMsg)
+
+	args := []string{"-n"}
+	out, err := parseReturnStderr(t, f, args)
+	if err != nil {
+		t.Fatal("expected no error; got ", err)
+	}
+
+	if !strings.Contains(out, usageMsg) {
+		t.Errorf("usageMsg not printed when using a deprecated flag!")
+	}
+}
+
+func TestDeprecatedFlagUsageNormalized(t *testing.T) {
+	f := NewFlagSet("bob", ContinueOnError)
+	f.Bool("bad-double_flag", true, "always true")
+	f.SetNormalizeFunc(wordSepNormalizeFunc)
+	usageMsg := "use --good-flag instead"
+	f.MarkDeprecated("bad_double-flag", usageMsg)
+
+	args := []string{"--bad_double_flag"}
+	out, err := parseReturnStderr(t, f, args)
+	if err != nil {
+		t.Fatal("expected no error; got ", err)
+	}
+
+	if !strings.Contains(out, usageMsg) {
+		t.Errorf("usageMsg not printed when using a deprecated flag!")
+	}
+}
+
+// Name normalization function should be called only once on flag addition
+func TestMultipleNormalizeFlagNameInvocations(t *testing.T) {
+	normalizeFlagNameInvocations = 0
+
+	f := NewFlagSet("normalized", ContinueOnError)
+	f.SetNormalizeFunc(wordSepNormalizeFunc)
+	f.Bool("with_under_flag", false, "bool value")
+
+	if normalizeFlagNameInvocations != 1 {
+		t.Fatal("Expected normalizeFlagNameInvocations to be 1; got ", normalizeFlagNameInvocations)
+	}
+}
+
+//
+func TestHiddenFlagInUsage(t *testing.T) {
+	f := NewFlagSet("bob", ContinueOnError)
+	f.Bool("secretFlag", true, "shhh")
+	f.MarkHidden("secretFlag")
+
+	out := new(bytes.Buffer)
+	f.SetOutput(out)
+	f.PrintDefaults()
+
+	if strings.Contains(out.String(), "secretFlag") {
+		t.Errorf("found hidden flag in usage!")
+	}
+}
+
+//
+func TestHiddenFlagUsage(t *testing.T) {
+	f := NewFlagSet("bob", ContinueOnError)
+	f.Bool("secretFlag", true, "shhh")
+	f.MarkHidden("secretFlag")
+
+	args := []string{"--secretFlag"}
+	out, err := parseReturnStderr(t, f, args)
+	if err != nil {
+		t.Fatal("expected no error; got ", err)
+	}
+
+	if strings.Contains(out, "shhh") {
+		t.Errorf("usage message printed when using a hidden flag!")
+	}
+}
+
+const defaultOutput = `      --A                    for bootstrapping, allow 'any' type
+      --Alongflagname        disable bounds checking
+  -C, --CCC                  a boolean defaulting to true (default true)
+      --D path               set relative path for local imports
+      --F number             a non-zero number (default 2.7)
+      --G float              a float that defaults to zero
+      --N int                a non-zero int (default 27)
+      --ND1 string[="bar"]   a string with NoOptDefVal (default "foo")
+      --ND2 num[=4321]       a num with NoOptDefVal (default 1234)
+      --Z int                an int that defaults to zero
+      --maxT timeout         set timeout for dial
+`
+
+func TestPrintDefaults(t *testing.T) {
+	fs := NewFlagSet("print defaults test", ContinueOnError)
+	var buf bytes.Buffer
+	fs.SetOutput(&buf)
+	fs.Bool("A", false, "for bootstrapping, allow 'any' type")
+	fs.Bool("Alongflagname", false, "disable bounds checking")
+	fs.BoolP("CCC", "C", true, "a boolean defaulting to true")
+	fs.String("D", "", "set relative `path` for local imports")
+	fs.Float64("F", 2.7, "a non-zero `number`")
+	fs.Float64("G", 0, "a float that defaults to zero")
+	fs.Int("N", 27, "a non-zero int")
+	fs.Int("Z", 0, "an int that defaults to zero")
+	fs.Duration("maxT", 0, "set `timeout` for dial")
+	fs.String("ND1", "foo", "a string with NoOptDefVal")
+	fs.Lookup("ND1").NoOptDefVal = "bar"
+	fs.Int("ND2", 1234, "a `num` with NoOptDefVal")
+	fs.Lookup("ND2").NoOptDefVal = "4321"
+	fs.PrintDefaults()
+	got := buf.String()
+	if got != defaultOutput {
+		fmt.Println("\n" + got)
+		fmt.Println("\n" + defaultOutput)
+		t.Errorf("got %q want %q\n", got, defaultOutput)
+	}
+}