go-arg/usage_test.go

1018 lines
26 KiB
Go

package arg
import (
"bytes"
"errors"
"fmt"
"os"
"strings"
"testing"
"github.com/stretchr/testify/assert"
"github.com/stretchr/testify/require"
)
type NameDotName struct {
Head, Tail string
}
func (n *NameDotName) UnmarshalText(b []byte) error {
s := string(b)
pos := strings.Index(s, ".")
if pos == -1 {
return fmt.Errorf("missing period in %s", s)
}
n.Head = s[:pos]
n.Tail = s[pos+1:]
return nil
}
func (n *NameDotName) MarshalText() (text []byte, err error) {
text = []byte(fmt.Sprintf("%s.%s", n.Head, n.Tail))
return
}
func TestWriteUsage(t *testing.T) {
expectedUsage := "Usage: example [--name NAME] [--value VALUE] [--verbose] [--dataset DATASET] [--optimize OPTIMIZE] [--ids IDS] [--values VALUES] [--workers WORKERS] [--testenv TESTENV] [--file FILE] INPUT [OUTPUT [OUTPUT ...]]"
expectedHelp := `
Usage: example [--name NAME] [--value VALUE] [--verbose] [--dataset DATASET] [--optimize OPTIMIZE] [--ids IDS] [--values VALUES] [--workers WORKERS] [--testenv TESTENV] [--file FILE] INPUT [OUTPUT [OUTPUT ...]]
Positional arguments:
INPUT
OUTPUT list of outputs
Options:
--name NAME name to use [default: Foo Bar]
--value VALUE secret value [default: 42]
--verbose, -v verbosity level
--dataset DATASET dataset to use
--optimize OPTIMIZE, -O OPTIMIZE
optimization level
--ids IDS Ids
--values VALUES Values
--workers WORKERS, -w WORKERS
number of workers to start [default: 10, env: WORKERS]
--testenv TESTENV, -a TESTENV [env: TEST_ENV]
--file FILE, -f FILE File with mandatory extension [default: scratch.txt]
--help, -h display this help and exit
Environment variables:
API_KEY Required. Only via env-var for security reasons
TRACE Optional. Record low-level trace
`
var args struct {
Input string `arg:"positional,required"`
Output []string `arg:"positional" help:"list of outputs"`
Name string `help:"name to use"`
Value int `help:"secret value"`
Verbose bool `arg:"-v" help:"verbosity level"`
Dataset string `help:"dataset to use"`
Optimize int `arg:"-O" help:"optimization level"`
Ids []int64 `help:"Ids"`
Values []float64 `help:"Values"`
Workers int `arg:"-w,env:WORKERS" help:"number of workers to start" default:"10"`
TestEnv string `arg:"-a,env:TEST_ENV"`
ApiKey string `arg:"required,-,--,env:API_KEY" help:"Only via env-var for security reasons"`
Trace bool `arg:"-,--,env" help:"Record low-level trace"`
File *NameDotName `arg:"-f" help:"File with mandatory extension"`
}
args.Name = "Foo Bar"
args.Value = 42
args.File = &NameDotName{"scratch", "txt"}
p, err := NewParser(Config{Program: "example"}, &args)
require.NoError(t, err)
os.Args[0] = "example"
var help bytes.Buffer
p.WriteHelp(&help)
assert.Equal(t, expectedHelp[1:], help.String())
var usage bytes.Buffer
p.WriteUsage(&usage)
assert.Equal(t, expectedUsage, strings.TrimSpace(usage.String()))
}
type MyEnum int
func (n *MyEnum) UnmarshalText(b []byte) error {
return nil
}
func (n *MyEnum) MarshalText() ([]byte, error) {
return nil, errors.New("There was a problem")
}
func TestUsageWithDefaults(t *testing.T) {
expectedUsage := "Usage: example [--label LABEL] [--content CONTENT]"
expectedHelp := `
Usage: example [--label LABEL] [--content CONTENT]
Options:
--label LABEL [default: cat]
--content CONTENT [default: dog]
--help, -h display this help and exit
`
var args struct {
Label string
Content string `default:"dog"`
}
args.Label = "cat"
p, err := NewParser(Config{Program: "example"}, &args)
require.NoError(t, err)
args.Label = "should_ignore_this"
var help bytes.Buffer
p.WriteHelp(&help)
assert.Equal(t, expectedHelp[1:], help.String())
var usage bytes.Buffer
p.WriteUsage(&usage)
assert.Equal(t, expectedUsage, strings.TrimSpace(usage.String()))
}
func TestUsageCannotMarshalToString(t *testing.T) {
var args struct {
Name *MyEnum
}
v := MyEnum(42)
args.Name = &v
_, err := NewParser(Config{Program: "example"}, &args)
assert.EqualError(t, err, `args.Name: error marshaling default value to string: There was a problem`)
}
func TestUsageLongPositionalWithHelp_legacyForm(t *testing.T) {
expectedUsage := "Usage: example [VERYLONGPOSITIONALWITHHELP]"
expectedHelp := `
Usage: example [VERYLONGPOSITIONALWITHHELP]
Positional arguments:
VERYLONGPOSITIONALWITHHELP
this positional argument is very long but cannot include commas
Options:
--help, -h display this help and exit
`
var args struct {
VeryLongPositionalWithHelp string `arg:"positional,help:this positional argument is very long but cannot include commas"`
}
p, err := NewParser(Config{Program: "example"}, &args)
require.NoError(t, err)
var help bytes.Buffer
p.WriteHelp(&help)
assert.Equal(t, expectedHelp[1:], help.String())
var usage bytes.Buffer
p.WriteUsage(&usage)
assert.Equal(t, expectedUsage, strings.TrimSpace(usage.String()))
}
func TestUsageLongPositionalWithHelp_newForm(t *testing.T) {
expectedUsage := "Usage: example [VERYLONGPOSITIONALWITHHELP]"
expectedHelp := `
Usage: example [VERYLONGPOSITIONALWITHHELP]
Positional arguments:
VERYLONGPOSITIONALWITHHELP
this positional argument is very long, and includes: commas, colons etc
Options:
--help, -h display this help and exit
`
var args struct {
VeryLongPositionalWithHelp string `arg:"positional" help:"this positional argument is very long, and includes: commas, colons etc"`
}
p, err := NewParser(Config{Program: "example"}, &args)
require.NoError(t, err)
var help bytes.Buffer
p.WriteHelp(&help)
assert.Equal(t, expectedHelp[1:], help.String())
var usage bytes.Buffer
p.WriteUsage(&usage)
assert.Equal(t, expectedUsage, strings.TrimSpace(usage.String()))
}
func TestUsageWithProgramName(t *testing.T) {
expectedUsage := "Usage: myprogram"
expectedHelp := `
Usage: myprogram
Options:
--help, -h display this help and exit
`
config := Config{
Program: "myprogram",
}
p, err := NewParser(config, &struct{}{})
require.NoError(t, err)
os.Args[0] = "example"
var help bytes.Buffer
p.WriteHelp(&help)
assert.Equal(t, expectedHelp[1:], help.String())
var usage bytes.Buffer
p.WriteUsage(&usage)
assert.Equal(t, expectedUsage, strings.TrimSpace(usage.String()))
}
type versioned struct{}
// Version returns the version for this program
func (versioned) Version() string {
return "example 3.2.1"
}
func TestUsageWithVersion(t *testing.T) {
expectedUsage := "example 3.2.1\nUsage: example"
expectedHelp := `
example 3.2.1
Usage: example
Options:
--help, -h display this help and exit
--version display version and exit
`
os.Args[0] = "example"
p, err := NewParser(Config{}, &versioned{})
require.NoError(t, err)
var help bytes.Buffer
p.WriteHelp(&help)
assert.Equal(t, expectedHelp[1:], help.String())
var usage bytes.Buffer
p.WriteUsage(&usage)
assert.Equal(t, expectedUsage, strings.TrimSpace(usage.String()))
}
func TestUsageWithUserDefinedVersionFlag(t *testing.T) {
expectedUsage := "Usage: example [--version]"
expectedHelp := `
Usage: example [--version]
Options:
--version this is a user-defined version flag
--help, -h display this help and exit
`
var args struct {
ShowVersion bool `arg:"--version" help:"this is a user-defined version flag"`
}
os.Args[0] = "example"
p, err := NewParser(Config{}, &args)
require.NoError(t, err)
var help bytes.Buffer
p.WriteHelp(&help)
assert.Equal(t, expectedHelp[1:], help.String())
var usage bytes.Buffer
p.WriteUsage(&usage)
assert.Equal(t, expectedUsage, strings.TrimSpace(usage.String()))
}
func TestUsageWithVersionAndUserDefinedVersionFlag(t *testing.T) {
expectedUsage := "Usage: example [--version]"
expectedHelp := `
Usage: example [--version]
Options:
--version this is a user-defined version flag
--help, -h display this help and exit
`
var args struct {
versioned
ShowVersion bool `arg:"--version" help:"this is a user-defined version flag"`
}
os.Args[0] = "example"
p, err := NewParser(Config{}, &args)
require.NoError(t, err)
var help bytes.Buffer
p.WriteHelp(&help)
assert.Equal(t, expectedHelp[1:], help.String())
var usage bytes.Buffer
p.WriteUsage(&usage)
assert.Equal(t, expectedUsage, strings.TrimSpace(usage.String()))
}
type subcommand struct {
Number int `arg:"-n,--number" help:"compute something on the given number"`
}
func TestUsageWithVersionAndSubcommand(t *testing.T) {
expectedUsage := "example 3.2.1\nUsage: example <command> [<args>]"
expectedHelp := `
example 3.2.1
Usage: example <command> [<args>]
Options:
--help, -h display this help and exit
--version display version and exit
Commands:
cmd
`
var args struct {
versioned
Cmd *subcommand `arg:"subcommand"`
}
os.Args[0] = "example"
p, err := NewParser(Config{}, &args)
require.NoError(t, err)
var help bytes.Buffer
p.WriteHelp(&help)
assert.Equal(t, expectedHelp[1:], help.String())
var usage bytes.Buffer
p.WriteUsage(&usage)
assert.Equal(t, expectedUsage, strings.TrimSpace(usage.String()))
expectedUsage = "example 3.2.1\nUsage: example cmd [--number NUMBER]"
expectedHelp = `
example 3.2.1
Usage: example cmd [--number NUMBER]
Options:
--number NUMBER, -n NUMBER
compute something on the given number
--help, -h display this help and exit
--version display version and exit
`
_ = p.Parse([]string{"cmd"})
help = bytes.Buffer{}
p.WriteHelp(&help)
assert.Equal(t, expectedHelp[1:], help.String())
usage = bytes.Buffer{}
p.WriteUsage(&usage)
assert.Equal(t, expectedUsage, strings.TrimSpace(usage.String()))
}
func TestUsageWithUserDefinedVersionFlagAndSubcommand(t *testing.T) {
expectedUsage := "Usage: example [--version] <command> [<args>]"
expectedHelp := `
Usage: example [--version] <command> [<args>]
Options:
--version this is a user-defined version flag
--help, -h display this help and exit
Commands:
cmd
`
var args struct {
Cmd *subcommand `arg:"subcommand"`
ShowVersion bool `arg:"--version" help:"this is a user-defined version flag"`
}
os.Args[0] = "example"
p, err := NewParser(Config{}, &args)
require.NoError(t, err)
var help bytes.Buffer
p.WriteHelp(&help)
assert.Equal(t, expectedHelp[1:], help.String())
var usage bytes.Buffer
p.WriteUsage(&usage)
assert.Equal(t, expectedUsage, strings.TrimSpace(usage.String()))
expectedUsage = "Usage: example cmd [--number NUMBER]"
expectedHelp = `
Usage: example cmd [--number NUMBER]
Options:
--number NUMBER, -n NUMBER
compute something on the given number
Global options:
--version this is a user-defined version flag
--help, -h display this help and exit
`
_ = p.Parse([]string{"cmd"})
help = bytes.Buffer{}
p.WriteHelp(&help)
assert.Equal(t, expectedHelp[1:], help.String())
usage = bytes.Buffer{}
p.WriteUsage(&usage)
assert.Equal(t, expectedUsage, strings.TrimSpace(usage.String()))
}
func TestUsageWithVersionAndUserDefinedVersionFlagAndSubcommand(t *testing.T) {
expectedUsage := "Usage: example [--version] <command> [<args>]"
expectedHelp := `
Usage: example [--version] <command> [<args>]
Options:
--version this is a user-defined version flag
--help, -h display this help and exit
Commands:
cmd
`
var args struct {
versioned
Cmd *subcommand `arg:"subcommand"`
ShowVersion bool `arg:"--version" help:"this is a user-defined version flag"`
}
os.Args[0] = "example"
p, err := NewParser(Config{}, &args)
require.NoError(t, err)
var help bytes.Buffer
p.WriteHelp(&help)
assert.Equal(t, expectedHelp[1:], help.String())
var usage bytes.Buffer
p.WriteUsage(&usage)
assert.Equal(t, expectedUsage, strings.TrimSpace(usage.String()))
expectedUsage = "Usage: example cmd [--number NUMBER]"
expectedHelp = `
Usage: example cmd [--number NUMBER]
Options:
--number NUMBER, -n NUMBER
compute something on the given number
Global options:
--version this is a user-defined version flag
--help, -h display this help and exit
`
_ = p.Parse([]string{"cmd"})
help = bytes.Buffer{}
p.WriteHelp(&help)
assert.Equal(t, expectedHelp[1:], help.String())
usage = bytes.Buffer{}
p.WriteUsage(&usage)
assert.Equal(t, expectedUsage, strings.TrimSpace(usage.String()))
}
type described struct{}
// Described returns the description for this program
func (described) Description() string {
return "this program does this and that"
}
func TestUsageWithDescription(t *testing.T) {
expectedUsage := "Usage: example"
expectedHelp := `
this program does this and that
Usage: example
Options:
--help, -h display this help and exit
`
os.Args[0] = "example"
p, err := NewParser(Config{}, &described{})
require.NoError(t, err)
var help bytes.Buffer
p.WriteHelp(&help)
assert.Equal(t, expectedHelp[1:], help.String())
var usage bytes.Buffer
p.WriteUsage(&usage)
assert.Equal(t, expectedUsage, strings.TrimSpace(usage.String()))
}
type epilogued struct{}
// Epilogued returns the epilogue for this program
func (epilogued) Epilogue() string {
return "For more information visit github.com/alexflint/go-arg"
}
func TestUsageWithEpilogue(t *testing.T) {
expectedUsage := "Usage: example"
expectedHelp := `
Usage: example
Options:
--help, -h display this help and exit
For more information visit github.com/alexflint/go-arg
`
os.Args[0] = "example"
p, err := NewParser(Config{}, &epilogued{})
require.NoError(t, err)
var help bytes.Buffer
p.WriteHelp(&help)
assert.Equal(t, expectedHelp[1:], help.String())
var usage bytes.Buffer
p.WriteUsage(&usage)
assert.Equal(t, expectedUsage, strings.TrimSpace(usage.String()))
}
func TestUsageForRequiredPositionals(t *testing.T) {
expectedUsage := "Usage: example REQUIRED1 REQUIRED2\n"
var args struct {
Required1 string `arg:"positional,required"`
Required2 string `arg:"positional,required"`
}
p, err := NewParser(Config{Program: "example"}, &args)
require.NoError(t, err)
var usage bytes.Buffer
p.WriteUsage(&usage)
assert.Equal(t, expectedUsage, usage.String())
}
func TestUsageForMixedPositionals(t *testing.T) {
expectedUsage := "Usage: example REQUIRED1 REQUIRED2 [OPTIONAL1 [OPTIONAL2]]\n"
var args struct {
Required1 string `arg:"positional,required"`
Required2 string `arg:"positional,required"`
Optional1 string `arg:"positional"`
Optional2 string `arg:"positional"`
}
p, err := NewParser(Config{Program: "example"}, &args)
require.NoError(t, err)
var usage bytes.Buffer
p.WriteUsage(&usage)
assert.Equal(t, expectedUsage, usage.String())
}
func TestUsageForRepeatedPositionals(t *testing.T) {
expectedUsage := "Usage: example REQUIRED1 REQUIRED2 REPEATED [REPEATED ...]\n"
var args struct {
Required1 string `arg:"positional,required"`
Required2 string `arg:"positional,required"`
Repeated []string `arg:"positional,required"`
}
p, err := NewParser(Config{Program: "example"}, &args)
require.NoError(t, err)
var usage bytes.Buffer
p.WriteUsage(&usage)
assert.Equal(t, expectedUsage, usage.String())
}
func TestUsageForMixedAndRepeatedPositionals(t *testing.T) {
expectedUsage := "Usage: example REQUIRED1 REQUIRED2 [OPTIONAL1 [OPTIONAL2 [REPEATED [REPEATED ...]]]]\n"
var args struct {
Required1 string `arg:"positional,required"`
Required2 string `arg:"positional,required"`
Optional1 string `arg:"positional"`
Optional2 string `arg:"positional"`
Repeated []string `arg:"positional"`
}
p, err := NewParser(Config{Program: "example"}, &args)
require.NoError(t, err)
var usage bytes.Buffer
p.WriteUsage(&usage)
assert.Equal(t, expectedUsage, usage.String())
}
func TestRequiredMultiplePositionals(t *testing.T) {
expectedUsage := "Usage: example REQUIREDMULTIPLE [REQUIREDMULTIPLE ...]\n"
expectedHelp := `
Usage: example REQUIREDMULTIPLE [REQUIREDMULTIPLE ...]
Positional arguments:
REQUIREDMULTIPLE required multiple positional
Options:
--help, -h display this help and exit
`
var args struct {
RequiredMultiple []string `arg:"positional,required" help:"required multiple positional"`
}
p, err := NewParser(Config{Program: "example"}, &args)
require.NoError(t, err)
var help bytes.Buffer
p.WriteHelp(&help)
assert.Equal(t, expectedHelp[1:], help.String())
var usage bytes.Buffer
p.WriteUsage(&usage)
assert.Equal(t, expectedUsage, usage.String())
}
func TestUsageWithSubcommands(t *testing.T) {
expectedUsage := "Usage: example child [--values VALUES]"
expectedHelp := `
Usage: example child [--values VALUES]
Options:
--values VALUES Values
Global options:
--verbose, -v verbosity level
--help, -h display this help and exit
`
var args struct {
Verbose bool `arg:"-v" help:"verbosity level"`
Child *struct {
Values []float64 `help:"Values"`
} `arg:"subcommand:child"`
}
os.Args[0] = "example"
p, err := NewParser(Config{}, &args)
require.NoError(t, err)
_ = p.Parse([]string{"child"})
var help bytes.Buffer
p.WriteHelp(&help)
assert.Equal(t, expectedHelp[1:], help.String())
var help2 bytes.Buffer
p.WriteHelpForSubcommand(&help2, "child")
assert.Equal(t, expectedHelp[1:], help2.String())
var usage bytes.Buffer
p.WriteUsage(&usage)
assert.Equal(t, expectedUsage, strings.TrimSpace(usage.String()))
var usage2 bytes.Buffer
p.WriteUsageForSubcommand(&usage2, "child")
assert.Equal(t, expectedUsage, strings.TrimSpace(usage2.String()))
}
func TestUsageWithNestedSubcommands(t *testing.T) {
expectedUsage := "Usage: example child nested [--enable] OUTPUT"
expectedHelp := `
Usage: example child nested [--enable] OUTPUT
Positional arguments:
OUTPUT
Options:
--enable
Global options:
--values VALUES Values
--verbose, -v verbosity level
--help, -h display this help and exit
`
var args struct {
Verbose bool `arg:"-v" help:"verbosity level"`
Child *struct {
Values []float64 `help:"Values"`
Nested *struct {
Enable bool
Output string `arg:"positional,required"`
} `arg:"subcommand:nested"`
} `arg:"subcommand:child"`
}
os.Args[0] = "example"
p, err := NewParser(Config{}, &args)
require.NoError(t, err)
_ = p.Parse([]string{"child", "nested", "value"})
assert.Equal(t, []string{"child", "nested"}, p.SubcommandNames())
var help bytes.Buffer
p.WriteHelp(&help)
assert.Equal(t, expectedHelp[1:], help.String())
var help2 bytes.Buffer
p.WriteHelpForSubcommand(&help2, "child", "nested")
assert.Equal(t, expectedHelp[1:], help2.String())
var usage bytes.Buffer
p.WriteUsage(&usage)
assert.Equal(t, expectedUsage, strings.TrimSpace(usage.String()))
var usage2 bytes.Buffer
p.WriteUsageForSubcommand(&usage2, "child", "nested")
assert.Equal(t, expectedUsage, strings.TrimSpace(usage2.String()))
}
func TestNonexistentSubcommand(t *testing.T) {
var args struct {
sub *struct{} `arg:"subcommand"`
}
p, err := NewParser(Config{Exit: func(int) {}}, &args)
require.NoError(t, err)
var b bytes.Buffer
err = p.WriteUsageForSubcommand(&b, "does_not_exist")
assert.Error(t, err)
err = p.WriteHelpForSubcommand(&b, "does_not_exist")
assert.Error(t, err)
err = p.FailSubcommand("something went wrong", "does_not_exist")
assert.Error(t, err)
err = p.WriteUsageForSubcommand(&b, "sub", "does_not_exist")
assert.Error(t, err)
err = p.WriteHelpForSubcommand(&b, "sub", "does_not_exist")
assert.Error(t, err)
err = p.FailSubcommand("something went wrong", "sub", "does_not_exist")
assert.Error(t, err)
}
func TestUsageWithoutLongNames(t *testing.T) {
expectedUsage := "Usage: example [-a PLACEHOLDER] -b SHORTONLY2"
expectedHelp := `
Usage: example [-a PLACEHOLDER] -b SHORTONLY2
Options:
-a PLACEHOLDER some help [default: some val]
-b SHORTONLY2 some help2
--help, -h display this help and exit
`
var args struct {
ShortOnly string `arg:"-a,--" help:"some help" default:"some val" placeholder:"PLACEHOLDER"`
ShortOnly2 string `arg:"-b,--,required" help:"some help2"`
}
p, err := NewParser(Config{Program: "example"}, &args)
require.NoError(t, err)
var help bytes.Buffer
p.WriteHelp(&help)
assert.Equal(t, expectedHelp[1:], help.String())
var usage bytes.Buffer
p.WriteUsage(&usage)
assert.Equal(t, expectedUsage, strings.TrimSpace(usage.String()))
}
func TestUsageWithEmptyPlaceholder(t *testing.T) {
expectedUsage := "Usage: example [-a] [--b] [--c]"
expectedHelp := `
Usage: example [-a] [--b] [--c]
Options:
-a some help for a
--b some help for b
--c, -c some help for c
--help, -h display this help and exit
`
var args struct {
ShortOnly string `arg:"-a,--" placeholder:"" help:"some help for a"`
LongOnly string `arg:"--b" placeholder:"" help:"some help for b"`
Both string `arg:"-c,--c" placeholder:"" help:"some help for c"`
}
p, err := NewParser(Config{Program: "example"}, &args)
require.NoError(t, err)
var help bytes.Buffer
p.WriteHelp(&help)
assert.Equal(t, expectedHelp[1:], help.String())
var usage bytes.Buffer
p.WriteUsage(&usage)
assert.Equal(t, expectedUsage, strings.TrimSpace(usage.String()))
}
func TestUsageWithShortFirst(t *testing.T) {
expectedUsage := "Usage: example [-c CAT] [--dog DOG]"
expectedHelp := `
Usage: example [-c CAT] [--dog DOG]
Options:
-c CAT
--dog DOG
--help, -h display this help and exit
`
var args struct {
Dog string
Cat string `arg:"-c,--"`
}
p, err := NewParser(Config{Program: "example"}, &args)
assert.NoError(t, err)
var help bytes.Buffer
p.WriteHelp(&help)
assert.Equal(t, expectedHelp[1:], help.String())
var usage bytes.Buffer
p.WriteUsage(&usage)
assert.Equal(t, expectedUsage, strings.TrimSpace(usage.String()))
}
func TestUsageWithEnvOptions(t *testing.T) {
expectedUsage := "Usage: example [-s SHORT]"
expectedHelp := `
Usage: example [-s SHORT]
Options:
-s SHORT [env: SHORT]
--help, -h display this help and exit
Environment variables:
ENVONLY Optional.
ENVONLY2 Optional.
CUSTOM Optional.
`
var args struct {
Short string `arg:"--,-s,env"`
EnvOnly string `arg:"--,env"`
EnvOnly2 string `arg:"--,-,env"`
EnvOnlyOverriden string `arg:"--,env:CUSTOM"`
}
p, err := NewParser(Config{Program: "example"}, &args)
assert.NoError(t, err)
var help bytes.Buffer
p.WriteHelp(&help)
assert.Equal(t, expectedHelp[1:], help.String())
var usage bytes.Buffer
p.WriteUsage(&usage)
assert.Equal(t, expectedUsage, strings.TrimSpace(usage.String()))
}
func TestEnvOnlyArgs(t *testing.T) {
expectedUsage := "Usage: example [--arg ARG]"
expectedHelp := `
Usage: example [--arg ARG]
Options:
--arg ARG, -a ARG [env: MY_ARG]
--help, -h display this help and exit
Environment variables:
AUTH_KEY Required.
`
var args struct {
ArgParam string `arg:"-a,--arg,env:MY_ARG"`
AuthKey string `arg:"required,--,env:AUTH_KEY"`
}
p, err := NewParser(Config{Program: "example"}, &args)
assert.NoError(t, err)
var help bytes.Buffer
p.WriteHelp(&help)
assert.Equal(t, expectedHelp[1:], help.String())
var usage bytes.Buffer
p.WriteUsage(&usage)
assert.Equal(t, expectedUsage, strings.TrimSpace(usage.String()))
}
func TestFail(t *testing.T) {
var stdout bytes.Buffer
var exitCode int
exit := func(code int) { exitCode = code }
expectedStdout := `
Usage: example [--foo FOO]
error: something went wrong
`
var args struct {
Foo int
}
p, err := NewParser(Config{Program: "example", Exit: exit, Out: &stdout}, &args)
require.NoError(t, err)
p.Fail("something went wrong")
assert.Equal(t, expectedStdout[1:], stdout.String())
assert.Equal(t, 2, exitCode)
}
func TestFailSubcommand(t *testing.T) {
var stdout bytes.Buffer
var exitCode int
exit := func(code int) { exitCode = code }
expectedStdout := `
Usage: example sub
error: something went wrong
`
var args struct {
Sub *struct{} `arg:"subcommand"`
}
p, err := NewParser(Config{Program: "example", Exit: exit, Out: &stdout}, &args)
require.NoError(t, err)
err = p.FailSubcommand("something went wrong", "sub")
require.NoError(t, err)
assert.Equal(t, expectedStdout[1:], stdout.String())
assert.Equal(t, 2, exitCode)
}
type lengthOf struct {
Length int
}
func (p *lengthOf) UnmarshalText(b []byte) error {
p.Length = len(b)
return nil
}
func TestHelpShowsDefaultValueFromOriginalTag(t *testing.T) {
// check that the usage text prints the original string from the default tag, not
// the serialization of the parsed value
expectedHelp := `
Usage: example [--test TEST]
Options:
--test TEST [default: some_default_value]
--help, -h display this help and exit
`
var args struct {
Test *lengthOf `default:"some_default_value"`
}
p, err := NewParser(Config{Program: "example"}, &args)
require.NoError(t, err)
var help bytes.Buffer
p.WriteHelp(&help)
assert.Equal(t, expectedHelp[1:], help.String())
}
func TestHelpShowsSubcommandAliases(t *testing.T) {
expectedHelp := `
Usage: example <command> [<args>]
Options:
--help, -h display this help and exit
Commands:
remove, rm, r remove something from somewhere
simple do something simple
halt, stop stop now
`
var args struct {
Remove *struct{} `arg:"subcommand:remove|rm|r" help:"remove something from somewhere"`
Simple *struct{} `arg:"subcommand" help:"do something simple"`
Stop *struct{} `arg:"subcommand:halt|stop" help:"stop now"`
}
p, err := NewParser(Config{Program: "example"}, &args)
require.NoError(t, err)
var help bytes.Buffer
p.WriteHelp(&help)
assert.Equal(t, expectedHelp[1:], help.String())
}