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flag_test.go
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flag_test.go
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// 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 flag_test
import (
"bytes"
"fmt"
"io"
"os"
"sort"
"strconv"
"strings"
"testing"
"time"
. "github.com/jnovack/flag"
)
func boolString(s string) string {
if s == "0" {
return "false"
}
return "true"
}
func TestEverything(t *testing.T) {
ResetForTesting(nil)
Bool("test_bool", false, "bool value")
Int("test_int", 0, "int value")
Int64("test_int64", 0, "int64 value")
Uint("test_uint", 0, "uint value")
Uint64("test_uint64", 0, "uint64 value")
String("test_string", "0", "string value")
Float64("test_float64", 0, "float64 value")
Duration("test_duration", 0, "time.Duration value")
Func("test_func", "func value", func(string) error { return nil })
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
case f.Name == "test_func" && f.Value.String() == "":
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_func", "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 TestGet(t *testing.T) {
ResetForTesting(nil)
Bool("test_bool", true, "bool value")
Int("test_int", 1, "int value")
Int64("test_int64", 2, "int64 value")
Uint("test_uint", 3, "uint value")
Uint64("test_uint64", 4, "uint64 value")
String("test_string", "5", "string value")
Float64("test_float64", 6, "float64 value")
Duration("test_duration", 7, "time.Duration value")
visitor := func(f *Flag) {
if len(f.Name) > 5 && f.Name[0:5] == "test_" {
g, ok := f.Value.(Getter)
if !ok {
t.Errorf("Visit: value does not satisfy Getter: %T", f.Value)
return
}
switch f.Name {
case "test_bool":
ok = g.Get() == true
case "test_int":
ok = g.Get() == int(1)
case "test_int64":
ok = g.Get() == int64(2)
case "test_uint":
ok = g.Get() == uint(3)
case "test_uint64":
ok = g.Get() == uint64(4)
case "test_string":
ok = g.Get() == "5"
case "test_float64":
ok = g.Get() == float64(6)
case "test_duration":
ok = g.Get() == time.Duration(7)
}
if !ok {
t.Errorf("Visit: bad value %T(%v) for %s", g.Get(), g.Get(), f.Name)
}
}
}
VisitAll(visitor)
}
func TestUsage(t *testing.T) {
called := false
ResetForTesting(func() { called = true })
if CommandLine.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 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")
intFlag := f.Int("int", 0, "int value")
int64Flag := f.Int64("int64", 0, "int64 value")
uintFlag := f.Uint("uint", 0, "uint value")
uint64Flag := f.Uint64("uint64", 0, "uint64 value")
stringFlag := f.String("string", "0", "string value")
float64Flag := f.Float64("float64", 0, "float64 value")
durationFlag := f.Duration("duration", 5*time.Second, "time.Duration value")
extra := "one-extra-argument"
args := []string{
"-bool",
"-bool2=true",
"--int", "22",
"--int64", "0x23",
"-uint", "24",
"--uint64", "25",
"-string", "hello",
"-float64", "2718e28",
"-duration", "2m",
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 *bool2Flag != true {
t.Error("bool2 flag should be true, is ", *bool2Flag)
}
if *intFlag != 22 {
t.Error("int flag should be 22, is ", *intFlag)
}
if *int64Flag != 0x23 {
t.Error("int64 flag should be 0x23, is ", *int64Flag)
}
if *uintFlag != 24 {
t.Error("uint flag should be 24, is ", *uintFlag)
}
if *uint64Flag != 25 {
t.Error("uint64 flag should be 25, is ", *uint64Flag)
}
if *stringFlag != "hello" {
t.Error("string flag should be `hello`, is ", *stringFlag)
}
if *float64Flag != 2718e28 {
t.Error("float64 flag should be 2718e28, is ", *float64Flag)
}
if *durationFlag != 2*time.Minute {
t.Error("duration flag should be 2m, is ", *durationFlag)
}
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 TestParse(t *testing.T) {
ResetForTesting(func() { t.Error("bad parse") })
testParse(CommandLine, t)
}
func TestFlagSetParse(t *testing.T) {
testParse(NewFlagSet("test", ContinueOnError), t)
}
// 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 TestUserDefined(t *testing.T) {
var flags FlagSet
flags.Init("test", ContinueOnError)
var v flagVar
flags.Var(&v, "v", "usage")
if err := flags.Parse([]string{"-v", "1", "-v", "2", "-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 TestUserDefinedFunc(t *testing.T) {
var flags FlagSet
flags.Init("test", ContinueOnError)
var ss []string
flags.Func("v", "usage", func(s string) error {
ss = append(ss, s)
return nil
})
if err := flags.Parse([]string{"-v", "1", "-v", "2", "-v=3"}); err != nil {
t.Error(err)
}
if len(ss) != 3 {
t.Fatal("expected 3 args; got ", len(ss))
}
expect := "[1 2 3]"
if got := fmt.Sprint(ss); got != expect {
t.Errorf("expected value %q got %q", expect, got)
}
// test usage
var buf strings.Builder
flags.SetOutput(&buf)
flags.Parse([]string{"-h"})
if usage := buf.String(); !strings.Contains(usage, "usage") {
t.Errorf("usage string not included: %q", usage)
}
// test Func error
flags = *NewFlagSet("test", ContinueOnError)
flags.Func("v", "usage", func(s string) error {
return fmt.Errorf("test error")
})
// flag not set, so no error
if err := flags.Parse(nil); err != nil {
t.Error(err)
}
// flag set, expect error
if err := flags.Parse([]string{"-v", "1"}); err == nil {
t.Error("expected error; got none")
} else if errMsg := err.Error(); !strings.Contains(errMsg, "test error") {
t.Errorf(`error should contain "test error"; got %q`, errMsg)
}
}
func TestUserDefinedForCommandLine(t *testing.T) {
const help = "HELP"
var result string
ResetForTesting(func() { result = help })
Usage()
if result != help {
t.Fatalf("got %q; expected %q", result, help)
}
}
// Declare a user-defined boolean flag type.
type boolFlagVar struct {
count int
}
func (b *boolFlagVar) String() string {
return fmt.Sprintf("%d", b.count)
}
func (b *boolFlagVar) Set(value string) error {
if value == "true" {
b.count++
}
return nil
}
func (b *boolFlagVar) IsBoolFlag() bool {
return b.count < 4
}
func TestUserDefinedBool(t *testing.T) {
var flags FlagSet
flags.Init("test", ContinueOnError)
var b boolFlagVar
var err error
flags.Var(&b, "b", "usage")
if err = flags.Parse([]string{"-b", "-b", "-b", "-b=true", "-b=false", "-b", "barg", "-b"}); err != nil {
if b.count < 4 {
t.Error(err)
}
}
if b.count != 4 {
t.Errorf("want: %d; got: %d", 4, b.count)
}
if err == nil {
t.Error("expected error; got none")
}
}
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", "-after", "args"}
before := Bool("before", false, "")
if err := CommandLine.Parse(os.Args[1:]); err != nil {
t.Fatal(err)
}
cmd := Arg(0)
os.Args = 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")
}
}
const defaultOutput = ` -A for bootstrapping, allow 'any' type
-Alongflagname
disable bounds checking
-C a boolean defaulting to true (default true)
-D path
set relative path for local imports
-E string
issue 23543 (default "0")
-F number
a non-zero number (default 2.7)
-G float
a float that defaults to zero
-M string
a multiline
help
string
-N int
a non-zero int (default 27)
-O a flag
multiline help string (default true)
-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.Bool("C", true, "a boolean defaulting to true")
fs.String("D", "", "set relative `path` for local imports")
fs.String("E", "0", "issue 23543")
fs.Float64("F", 2.7, "a non-zero `number`")
fs.Float64("G", 0, "a float that defaults to zero")
fs.String("M", "", "a multiline\nhelp\nstring")
fs.Int("N", 27, "a non-zero int")
fs.Bool("O", true, "a flag\nmultiline help string")
fs.Int("Z", 0, "an int that defaults to zero")
fs.Duration("maxT", 0, "set `timeout` for dial")
fs.PrintDefaults()
got := buf.String()
if got != defaultOutput {
t.Errorf("got %q want %q\n", got, defaultOutput)
}
}
// Issue 19230: validate range of Int and Uint flag values.
func TestIntFlagOverflow(t *testing.T) {
if strconv.IntSize != 32 {
return
}
ResetForTesting(nil)
Int("i", 0, "")
Uint("u", 0, "")
if err := Set("i", "2147483648"); err == nil {
t.Error("unexpected success setting Int")
}
if err := Set("u", "4294967296"); err == nil {
t.Error("unexpected success setting Uint")
}
}
// Issue 20998: Usage should respect CommandLine.output.
func TestUsageOutput(t *testing.T) {
ResetForTesting(DefaultUsage)
var buf bytes.Buffer
CommandLine.SetOutput(&buf)
defer func(old []string) { os.Args = old }(os.Args)
os.Args = []string{"app", "-i=1", "-unknown"}
Parse()
const want = "flag provided but not defined: -i\nUsage of app:\n"
if got := buf.String(); got != want {
t.Errorf("output = %q; want %q", got, want)
}
}
func TestGetters(t *testing.T) {
expectedName := "flag set"
expectedErrorHandling := ContinueOnError
expectedOutput := io.Writer(os.Stderr)
fs := NewFlagSet(expectedName, expectedErrorHandling)
if fs.Name() != expectedName {
t.Errorf("unexpected name: got %s, expected %s", fs.Name(), expectedName)
}
if fs.ErrorHandling() != expectedErrorHandling {
t.Errorf("unexpected ErrorHandling: got %d, expected %d", fs.ErrorHandling(), expectedErrorHandling)
}
if fs.Output() != expectedOutput {
t.Errorf("unexpected output: got %#v, expected %#v", fs.Output(), expectedOutput)
}
expectedName = "gopher"
expectedErrorHandling = ExitOnError
expectedOutput = os.Stdout
fs.Init(expectedName, expectedErrorHandling)
fs.SetOutput(expectedOutput)
if fs.Name() != expectedName {
t.Errorf("unexpected name: got %s, expected %s", fs.Name(), expectedName)
}
if fs.ErrorHandling() != expectedErrorHandling {
t.Errorf("unexpected ErrorHandling: got %d, expected %d", fs.ErrorHandling(), expectedErrorHandling)
}
if fs.Output() != expectedOutput {
t.Errorf("unexpected output: got %v, expected %v", fs.Output(), expectedOutput)
}
}
func TestParseError(t *testing.T) {
for _, typ := range []string{"bool", "int", "int64", "uint", "uint64", "float64", "duration"} {
fs := NewFlagSet("parse error test", ContinueOnError)
fs.SetOutput(io.Discard)
_ = fs.Bool("bool", false, "")
_ = fs.Int("int", 0, "")
_ = fs.Int64("int64", 0, "")
_ = fs.Uint("uint", 0, "")
_ = fs.Uint64("uint64", 0, "")
_ = fs.Float64("float64", 0, "")
_ = fs.Duration("duration", 0, "")
// Strings cannot give errors.
args := []string{"-" + typ + "=x"}
err := fs.Parse(args) // x is not a valid setting for any flag.
if err == nil {
t.Errorf("Parse(%q)=%v; expected parse error", args, err)
continue
}
if !strings.Contains(err.Error(), "invalid") || !strings.Contains(err.Error(), "parse error") {
t.Errorf("Parse(%q)=%v; expected parse error", args, err)
}
}
}
func TestRangeError(t *testing.T) {
bad := []string{
"-int=123456789012345678901",
"-int64=123456789012345678901",
"-uint=123456789012345678901",
"-uint64=123456789012345678901",
"-float64=1e1000",
}
for _, arg := range bad {
fs := NewFlagSet("parse error test", ContinueOnError)
fs.SetOutput(io.Discard)
_ = fs.Int("int", 0, "")
_ = fs.Int64("int64", 0, "")
_ = fs.Uint("uint", 0, "")
_ = fs.Uint64("uint64", 0, "")
_ = fs.Float64("float64", 0, "")
// Strings cannot give errors, and bools and durations do not return strconv.NumError.
err := fs.Parse([]string{arg})
if err == nil {
t.Errorf("Parse(%q)=%v; expected range error", arg, err)
continue
}
if !strings.Contains(err.Error(), "invalid") || !strings.Contains(err.Error(), "value out of range") {
t.Errorf("Parse(%q)=%v; expected range error", arg, err)
}
}
}
// jnovack/flag cannot import TextExitCode because it relies on internal/testenv
/*
func TestExitCode(t *testing.T) {
testenv.MustHaveExec(t)
magic := 123
if os.Getenv("GO_CHILD_FLAG") != "" {
fs := NewFlagSet("test", ExitOnError)
if os.Getenv("GO_CHILD_FLAG_HANDLE") != "" {
var b bool
fs.BoolVar(&b, os.Getenv("GO_CHILD_FLAG_HANDLE"), false, "")
}
fs.Parse([]string{os.Getenv("GO_CHILD_FLAG")})
os.Exit(magic)
}
tests := []struct {
flag string
flagHandle string
expectExit int
}{
{
flag: "-h",
expectExit: 0,
},
{
flag: "-help",
expectExit: 0,
},
{
flag: "-undefined",
expectExit: 2,
},
{
flag: "-h",
flagHandle: "h",
expectExit: magic,
},
{
flag: "-help",
flagHandle: "help",
expectExit: magic,
},
}
for _, test := range tests {
cmd := exec.Command(os.Args[0], "-test.run=TestExitCode")
cmd.Env = append(
os.Environ(),
"GO_CHILD_FLAG="+test.flag,
"GO_CHILD_FLAG_HANDLE="+test.flagHandle,
)
cmd.Run()
got := cmd.ProcessState.ExitCode()
// ExitCode is either 0 or 1 on Plan 9.
if runtime.GOOS == "plan9" && test.expectExit != 0 {
test.expectExit = 1
}
if got != test.expectExit {
t.Errorf("unexpected exit code for test case %+v \n: got %d, expect %d",
test, got, test.expectExit)
}
}
}
func mustPanic(t *testing.T, testName string, expected string, f func()) {
t.Helper()
defer func() {
switch msg := recover().(type) {
case nil:
t.Errorf("%s\n: expected panic(%q), but did not panic", testName, expected)
case string:
if msg != expected {
t.Errorf("%s\n: expected panic(%q), but got panic(%q)", testName, expected, msg)
}
default:
t.Errorf("%s\n: expected panic(%q), but got panic(%T%v)", testName, expected, msg, msg)
}
}()
f()
}
func TestInvalidFlags(t *testing.T) {
tests := []struct {
flag string
errorMsg string
}{
{
flag: "-foo",
errorMsg: "flag \"-foo\" begins with -",
},
{
flag: "foo=bar",
errorMsg: "flag \"foo=bar\" contains =",
},
}
for _, test := range tests {
testName := fmt.Sprintf("FlagSet.Var(&v, %q, \"\")", test.flag)
fs := NewFlagSet("", ContinueOnError)
buf := bytes.NewBuffer(nil)
fs.SetOutput(buf)
mustPanic(t, testName, test.errorMsg, func() {
var v flagVar
fs.Var(&v, test.flag, "")
})
if msg := test.errorMsg + "\n"; msg != buf.String() {
t.Errorf("%s\n: unexpected output: expected %q, bug got %q", testName, msg, buf)
}
}
}
func TestRedefinedFlags(t *testing.T) {
tests := []struct {
flagSetName string
errorMsg string
}{
{
flagSetName: "",
errorMsg: "flag redefined: foo",
},
{
flagSetName: "fs",
errorMsg: "fs flag redefined: foo",
},
}
for _, test := range tests {
testName := fmt.Sprintf("flag redefined in FlagSet(%q)", test.flagSetName)
fs := NewFlagSet(test.flagSetName, ContinueOnError)
buf := bytes.NewBuffer(nil)
fs.SetOutput(buf)
var v flagVar
fs.Var(&v, "foo", "")
mustPanic(t, testName, test.errorMsg, func() {
fs.Var(&v, "foo", "")
})
if msg := test.errorMsg + "\n"; msg != buf.String() {
t.Errorf("%s\n: unexpected output: expected %q, bug got %q", testName, msg, buf)
}
}
}
*/