try to get a clean go mod

Signed-off-by: Jeff Carr <jcarr@wit.com>

Makefile

@@ -1,23 +1,10 @@
-# git remote add gitwit git@git.wit.org:wit/arg.git
+all:
+	@echo
+	@echo "this is from alexflint's github repo"
+	@echo "the 'github' branch is the upstream branch"
+	@echo
 
 redomod:
 	rm -f go.*
 	GO111MODULE= go mod init
 	GO111MODULE= go mod tidy
-
-github:
-	git push origin register
-	git push origin devel
-	git push origin jcarr
-	git push origin --tags
-	# git push github register
-	# git push github devel
-	# git push github --tags
-	@echo
-	@echo check https://git.wit.org/wit/arg
-	@echo
-
-# init-github:
-# 	git push -u github master
-# 	git push -u github devel
-# 	git push github --tags

example_test.go

@@ -1,540 +0,0 @@
-package arg
-
-import (
-	"fmt"
-	"net"
-	"net/mail"
-	"net/url"
-	"os"
-	"strings"
-	"time"
-)
-
-func split(s string) []string {
-	return strings.Split(s, " ")
-}
-
-// This example demonstrates basic usage
-func Example() {
-	// These are the args you would pass in on the command line
-	os.Args = split("./example --foo=hello --bar")
-
-	var args struct {
-		Foo string
-		Bar bool
-	}
-	MustParse(&args)
-	fmt.Println(args.Foo, args.Bar)
-	// output: hello true
-}
-
-// This example demonstrates arguments that have default values
-func Example_defaultValues() {
-	// These are the args you would pass in on the command line
-	os.Args = split("./example")
-
-	var args struct {
-		Foo string `default:"abc"`
-	}
-	MustParse(&args)
-	fmt.Println(args.Foo)
-	// output: abc
-}
-
-// This example demonstrates arguments that are required
-func Example_requiredArguments() {
-	// These are the args you would pass in on the command line
-	os.Args = split("./example --foo=abc --bar")
-
-	var args struct {
-		Foo string `arg:"required"`
-		Bar bool
-	}
-	MustParse(&args)
-	fmt.Println(args.Foo, args.Bar)
-	// output: abc true
-}
-
-// This example demonstrates positional arguments
-func Example_positionalArguments() {
-	// These are the args you would pass in on the command line
-	os.Args = split("./example in out1 out2 out3")
-
-	var args struct {
-		Input  string   `arg:"positional"`
-		Output []string `arg:"positional"`
-	}
-	MustParse(&args)
-	fmt.Println("In:", args.Input)
-	fmt.Println("Out:", args.Output)
-	// output:
-	// In: in
-	// Out: [out1 out2 out3]
-}
-
-// This example demonstrates arguments that have multiple values
-func Example_multipleValues() {
-	// The args you would pass in on the command line
-	os.Args = split("./example --database localhost --ids 1 2 3")
-
-	var args struct {
-		Database string
-		IDs      []int64
-	}
-	MustParse(&args)
-	fmt.Printf("Fetching the following IDs from %s: %v", args.Database, args.IDs)
-	// output: Fetching the following IDs from localhost: [1 2 3]
-}
-
-// This example demonstrates arguments with keys and values
-func Example_mappings() {
-	// The args you would pass in on the command line
-	os.Args = split("./example --userids john=123 mary=456")
-
-	var args struct {
-		UserIDs map[string]int
-	}
-	MustParse(&args)
-	fmt.Println(args.UserIDs)
-	// output: map[john:123 mary:456]
-}
-
-type commaSeparated struct {
-	M map[string]string
-}
-
-func (c *commaSeparated) UnmarshalText(b []byte) error {
-	c.M = make(map[string]string)
-	for _, part := range strings.Split(string(b), ",") {
-		pos := strings.Index(part, "=")
-		if pos == -1 {
-			return fmt.Errorf("error parsing %q, expected format key=value", part)
-		}
-		c.M[part[:pos]] = part[pos+1:]
-	}
-	return nil
-}
-
-// This example demonstrates arguments with keys and values separated by commas
-func Example_mappingWithCommas() {
-	// The args you would pass in on the command line
-	os.Args = split("./example --values one=two,three=four")
-
-	var args struct {
-		Values commaSeparated
-	}
-	MustParse(&args)
-	fmt.Println(args.Values.M)
-	// output: map[one:two three:four]
-}
-
-// This eample demonstrates multiple value arguments that can be mixed with
-// other arguments.
-func Example_multipleMixed() {
-	os.Args = split("./example -c cmd1 db1 -f file1 db2 -c cmd2 -f file2 -f file3 db3 -c cmd3")
-	var args struct {
-		Commands  []string `arg:"-c,separate"`
-		Files     []string `arg:"-f,separate"`
-		Databases []string `arg:"positional"`
-	}
-	MustParse(&args)
-	fmt.Println("Commands:", args.Commands)
-	fmt.Println("Files:", args.Files)
-	fmt.Println("Databases:", args.Databases)
-
-	// output:
-	// Commands: [cmd1 cmd2 cmd3]
-	// Files: [file1 file2 file3]
-	// Databases: [db1 db2 db3]
-}
-
-// This example shows the usage string generated by go-arg
-func Example_helpText() {
-	// These are the args you would pass in on the command line
-	os.Args = split("./example --help")
-
-	var args struct {
-		Input    string   `arg:"positional,required"`
-		Output   []string `arg:"positional"`
-		Verbose  bool     `arg:"-v" help:"verbosity level"`
-		Dataset  string   `help:"dataset to use"`
-		Optimize int      `arg:"-O,--optim" help:"optimization level"`
-	}
-
-	// This is only necessary when running inside golang's runnable example harness
-	mustParseExit = func(int) {}
-
-	MustParse(&args)
-
-	// output:
-	// Usage: example [--verbose] [--dataset DATASET] [--optim OPTIM] INPUT [OUTPUT [OUTPUT ...]]
-	//
-	// Positional arguments:
-	//   INPUT
-	//   OUTPUT
-	//
-	// Options:
-	//   --verbose, -v          verbosity level
-	//   --dataset DATASET      dataset to use
-	//   --optim OPTIM, -O OPTIM
-	//                          optimization level
-	//   --help, -h             display this help and exit
-}
-
-// This example shows the usage string generated by go-arg with customized placeholders
-func Example_helpPlaceholder() {
-	// These are the args you would pass in on the command line
-	os.Args = split("./example --help")
-
-	var args struct {
-		Input    string   `arg:"positional,required" placeholder:"SRC"`
-		Output   []string `arg:"positional" placeholder:"DST"`
-		Optimize int      `arg:"-O" help:"optimization level" placeholder:"LEVEL"`
-		MaxJobs  int      `arg:"-j" help:"maximum number of simultaneous jobs" placeholder:"N"`
-	}
-
-	// This is only necessary when running inside golang's runnable example harness
-	mustParseExit = func(int) {}
-
-	MustParse(&args)
-
-	// output:
-
-	// Usage: example [--optimize LEVEL] [--maxjobs N] SRC [DST [DST ...]]
-
-	// Positional arguments:
-	//   SRC
-	//   DST
-
-	// Options:
-	//   --optimize LEVEL, -O LEVEL
-	//                          optimization level
-	//   --maxjobs N, -j N      maximum number of simultaneous jobs
-	//   --help, -h             display this help and exit
-}
-
-// This example shows the usage string generated by go-arg when using subcommands
-func Example_helpTextWithSubcommand() {
-	// These are the args you would pass in on the command line
-	os.Args = split("./example --help")
-
-	type getCmd struct {
-		Item string `arg:"positional" help:"item to fetch"`
-	}
-
-	type listCmd struct {
-		Format string `help:"output format"`
-		Limit  int
-	}
-
-	var args struct {
-		Verbose bool
-		Get     *getCmd  `arg:"subcommand" help:"fetch an item and print it"`
-		List    *listCmd `arg:"subcommand" help:"list available items"`
-	}
-
-	// This is only necessary when running inside golang's runnable example harness
-	mustParseExit = func(int) {}
-
-	MustParse(&args)
-
-	// output:
-	// Usage: example [--verbose] <command> [<args>]
-	//
-	// Options:
-	//   --verbose
-	//   --help, -h             display this help and exit
-	//
-	// Commands:
-	//   get                    fetch an item and print it
-	//   list                   list available items
-}
-
-// This example shows the usage string generated by go-arg when using subcommands
-func Example_helpTextWhenUsingSubcommand() {
-	// These are the args you would pass in on the command line
-	os.Args = split("./example get --help")
-
-	type getCmd struct {
-		Item string `arg:"positional,required" help:"item to fetch"`
-	}
-
-	type listCmd struct {
-		Format string `help:"output format"`
-		Limit  int
-	}
-
-	var args struct {
-		Verbose bool
-		Get     *getCmd  `arg:"subcommand" help:"fetch an item and print it"`
-		List    *listCmd `arg:"subcommand" help:"list available items"`
-	}
-
-	// This is only necessary when running inside golang's runnable example harness
-	mustParseExit = func(int) {}
-
-	MustParse(&args)
-
-	// output:
-	// Usage: example get ITEM
-	//
-	// Positional arguments:
-	//   ITEM                   item to fetch
-	//
-	// Global options:
-	//   --verbose
-	//   --help, -h             display this help and exit
-}
-
-// This example shows how to print help for an explicit subcommand
-func Example_writeHelpForSubcommand() {
-	// These are the args you would pass in on the command line
-	os.Args = split("./example get --help")
-
-	type getCmd struct {
-		Item string `arg:"positional" help:"item to fetch"`
-	}
-
-	type listCmd struct {
-		Format string `help:"output format"`
-		Limit  int
-	}
-
-	var args struct {
-		Verbose bool
-		Get     *getCmd  `arg:"subcommand" help:"fetch an item and print it"`
-		List    *listCmd `arg:"subcommand" help:"list available items"`
-	}
-
-	// This is only necessary when running inside golang's runnable example harness
-	exit := func(int) {}
-
-	p, err := NewParser(Config{Exit: exit}, &args)
-	if err != nil {
-		fmt.Println(err)
-		os.Exit(1)
-	}
-
-	err = p.WriteHelpForSubcommand(os.Stdout, "list")
-	if err != nil {
-		fmt.Println(err)
-		os.Exit(1)
-	}
-
-	// output:
-	// Usage: example list [--format FORMAT] [--limit LIMIT]
-	//
-	// Options:
-	//   --format FORMAT        output format
-	//   --limit LIMIT
-	//
-	// Global options:
-	//   --verbose
-	//   --help, -h             display this help and exit
-}
-
-// This example shows how to print help for a subcommand that is nested several levels deep
-func Example_writeHelpForSubcommandNested() {
-	// These are the args you would pass in on the command line
-	os.Args = split("./example get --help")
-
-	type mostNestedCmd struct {
-		Item string
-	}
-
-	type nestedCmd struct {
-		MostNested *mostNestedCmd `arg:"subcommand"`
-	}
-
-	type topLevelCmd struct {
-		Nested *nestedCmd `arg:"subcommand"`
-	}
-
-	var args struct {
-		TopLevel *topLevelCmd `arg:"subcommand"`
-	}
-
-	// This is only necessary when running inside golang's runnable example harness
-	exit := func(int) {}
-
-	p, err := NewParser(Config{Exit: exit}, &args)
-	if err != nil {
-		fmt.Println(err)
-		os.Exit(1)
-	}
-
-	err = p.WriteHelpForSubcommand(os.Stdout, "toplevel", "nested", "mostnested")
-	if err != nil {
-		fmt.Println(err)
-		os.Exit(1)
-	}
-
-	// output:
-	// Usage: example toplevel nested mostnested [--item ITEM]
-	//
-	// Options:
-	//   --item ITEM
-	//   --help, -h             display this help and exit
-}
-
-// This example shows the error string generated by go-arg when an invalid option is provided
-func Example_errorText() {
-	// These are the args you would pass in on the command line
-	os.Args = split("./example --optimize INVALID")
-
-	var args struct {
-		Input    string   `arg:"positional,required"`
-		Output   []string `arg:"positional"`
-		Verbose  bool     `arg:"-v" help:"verbosity level"`
-		Dataset  string   `help:"dataset to use"`
-		Optimize int      `arg:"-O,help:optimization level"`
-	}
-
-	// This is only necessary when running inside golang's runnable example harness
-	mustParseExit = func(int) {}
-
-	MustParse(&args)
-
-	// output:
-	// Usage: example [--verbose] [--dataset DATASET] [--optimize OPTIMIZE] INPUT [OUTPUT [OUTPUT ...]]
-	// error: error processing --optimize: strconv.ParseInt: parsing "INVALID": invalid syntax
-}
-
-// This example shows the error string generated by go-arg when an invalid option is provided
-func Example_errorTextForSubcommand() {
-	// These are the args you would pass in on the command line
-	os.Args = split("./example get --count INVALID")
-
-	type getCmd struct {
-		Count int
-	}
-
-	var args struct {
-		Get *getCmd `arg:"subcommand"`
-	}
-
-	// This is only necessary when running inside golang's runnable example harness
-	mustParseExit = func(int) {}
-
-	MustParse(&args)
-
-	// output:
-	// Usage: example get [--count COUNT]
-	// error: error processing --count: strconv.ParseInt: parsing "INVALID": invalid syntax
-}
-
-// This example demonstrates use of subcommands
-func Example_subcommand() {
-	// These are the args you would pass in on the command line
-	os.Args = split("./example commit -a -m what-this-commit-is-about")
-
-	type CheckoutCmd struct {
-		Branch string `arg:"positional"`
-		Track  bool   `arg:"-t"`
-	}
-	type CommitCmd struct {
-		All     bool   `arg:"-a"`
-		Message string `arg:"-m"`
-	}
-	type PushCmd struct {
-		Remote      string `arg:"positional"`
-		Branch      string `arg:"positional"`
-		SetUpstream bool   `arg:"-u"`
-	}
-	var args struct {
-		Checkout *CheckoutCmd `arg:"subcommand:checkout"`
-		Commit   *CommitCmd   `arg:"subcommand:commit"`
-		Push     *PushCmd     `arg:"subcommand:push"`
-		Quiet    bool         `arg:"-q"` // this flag is global to all subcommands
-	}
-
-	// This is only necessary when running inside golang's runnable example harness
-	mustParseExit = func(int) {}
-
-	MustParse(&args)
-
-	switch {
-	case args.Checkout != nil:
-		fmt.Printf("checkout requested for branch %s\n", args.Checkout.Branch)
-	case args.Commit != nil:
-		fmt.Printf("commit requested with message \"%s\"\n", args.Commit.Message)
-	case args.Push != nil:
-		fmt.Printf("push requested from %s to %s\n", args.Push.Branch, args.Push.Remote)
-	}
-
-	// output:
-	// commit requested with message "what-this-commit-is-about"
-}
-
-func Example_allSupportedTypes() {
-	// These are the args you would pass in on the command line
-	os.Args = []string{}
-
-	var args struct {
-		Bool     bool
-		Byte     byte
-		Rune     rune
-		Int      int
-		Int8     int8
-		Int16    int16
-		Int32    int32
-		Int64    int64
-		Float32  float32
-		Float64  float64
-		String   string
-		Duration time.Duration
-		URL      url.URL
-		Email    mail.Address
-		MAC      net.HardwareAddr
-	}
-
-	// go-arg supports each of the types above, as well as pointers to any of
-	// the above and slices of any of the above. It also supports any types that
-	// implements encoding.TextUnmarshaler.
-
-	MustParse(&args)
-
-	// output:
-}
-
-func Example_envVarOnly() {
-	os.Args = split("./example")
-	_ = os.Setenv("AUTH_KEY", "my_key")
-
-	defer os.Unsetenv("AUTH_KEY")
-
-	var args struct {
-		AuthKey string `arg:"--,env:AUTH_KEY"`
-	}
-
-	MustParse(&args)
-
-	fmt.Println(args.AuthKey)
-	// output: my_key
-}
-
-func Example_envVarOnlyShouldIgnoreFlag() {
-	os.Args = split("./example --=my_key")
-
-	var args struct {
-		AuthKey string `arg:"--,env:AUTH_KEY"`
-	}
-
-	err := Parse(&args)
-
-	fmt.Println(err)
-	// output: unknown argument --=my_key
-}
-
-func Example_envVarOnlyShouldIgnoreShortFlag() {
-	os.Args = split("./example -=my_key")
-
-	var args struct {
-		AuthKey string `arg:"--,env:AUTH_KEY"`
-	}
-
-	err := Parse(&args)
-
-	fmt.Println(err)
-	// output: unknown argument -=my_key
-}

go.mod

@@ -2,13 +2,4 @@ module go.wit.com/dev/alexflint/go-arg
 
 go 1.21.4
 
-require (
+require github.com/alexflint/go-scalar v1.2.0
-	github.com/alexflint/go-scalar v1.2.0
-	github.com/stretchr/testify v1.8.4
-)
-
-require (
-	github.com/davecgh/go-spew v1.1.1 // indirect
-	github.com/pmezard/go-difflib v1.0.0 // indirect
-	gopkg.in/yaml.v3 v3.0.1 // indirect
-)

go.sum

@@ -4,10 +4,5 @@ github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/stretchr/testify v1.2.2 h1:bSDNvY7ZPG5RlJ8otE/7V6gMiyenm9RtJ7IUVIAoJ1w=
 github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=
-github.com/stretchr/testify v1.8.4 h1:CcVxjf3Q8PM0mHUKJCdn+eZZtm5yQwehR5yeSVQQcUk=
-github.com/stretchr/testify v1.8.4/go.mod h1:sz/lmYIOXD/1dqDmKjjqLyZ2RngseejIcXlSw2iwfAo=
-gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
-gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
-gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
-gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

reflect_test.go

@@ -1,112 +0,0 @@
-package arg
-
-import (
-	"reflect"
-	"testing"
-
-	"github.com/stretchr/testify/assert"
-)
-
-func assertCardinality(t *testing.T, typ reflect.Type, expected cardinality) {
-	actual, err := cardinalityOf(typ)
-	assert.Equal(t, expected, actual, "expected %v to have cardinality %v but got %v", typ, expected, actual)
-	if expected == unsupported {
-		assert.Error(t, err)
-	}
-}
-
-func TestCardinalityOf(t *testing.T) {
-	var b bool
-	var i int
-	var s string
-	var f float64
-	var bs []bool
-	var is []int
-	var m map[string]int
-	var unsupported1 struct{}
-	var unsupported2 []struct{}
-	var unsupported3 map[string]struct{}
-	var unsupported4 map[struct{}]string
-
-	assertCardinality(t, reflect.TypeOf(b), zero)
-	assertCardinality(t, reflect.TypeOf(i), one)
-	assertCardinality(t, reflect.TypeOf(s), one)
-	assertCardinality(t, reflect.TypeOf(f), one)
-
-	assertCardinality(t, reflect.TypeOf(&b), zero)
-	assertCardinality(t, reflect.TypeOf(&s), one)
-	assertCardinality(t, reflect.TypeOf(&i), one)
-	assertCardinality(t, reflect.TypeOf(&f), one)
-
-	assertCardinality(t, reflect.TypeOf(bs), multiple)
-	assertCardinality(t, reflect.TypeOf(is), multiple)
-
-	assertCardinality(t, reflect.TypeOf(&bs), multiple)
-	assertCardinality(t, reflect.TypeOf(&is), multiple)
-
-	assertCardinality(t, reflect.TypeOf(m), multiple)
-	assertCardinality(t, reflect.TypeOf(&m), multiple)
-
-	assertCardinality(t, reflect.TypeOf(unsupported1), unsupported)
-	assertCardinality(t, reflect.TypeOf(&unsupported1), unsupported)
-	assertCardinality(t, reflect.TypeOf(unsupported2), unsupported)
-	assertCardinality(t, reflect.TypeOf(&unsupported2), unsupported)
-	assertCardinality(t, reflect.TypeOf(unsupported3), unsupported)
-	assertCardinality(t, reflect.TypeOf(&unsupported3), unsupported)
-	assertCardinality(t, reflect.TypeOf(unsupported4), unsupported)
-	assertCardinality(t, reflect.TypeOf(&unsupported4), unsupported)
-}
-
-type implementsTextUnmarshaler struct{}
-
-func (*implementsTextUnmarshaler) UnmarshalText(text []byte) error {
-	return nil
-}
-
-func TestCardinalityTextUnmarshaler(t *testing.T) {
-	var x implementsTextUnmarshaler
-	var s []implementsTextUnmarshaler
-	var m []implementsTextUnmarshaler
-	assertCardinality(t, reflect.TypeOf(x), one)
-	assertCardinality(t, reflect.TypeOf(&x), one)
-	assertCardinality(t, reflect.TypeOf(s), multiple)
-	assertCardinality(t, reflect.TypeOf(&s), multiple)
-	assertCardinality(t, reflect.TypeOf(m), multiple)
-	assertCardinality(t, reflect.TypeOf(&m), multiple)
-}
-
-func TestIsExported(t *testing.T) {
-	assert.True(t, isExported("Exported"))
-	assert.False(t, isExported("notExported"))
-	assert.False(t, isExported(""))
-	assert.False(t, isExported(string([]byte{255})))
-}
-
-func TestCardinalityString(t *testing.T) {
-	assert.Equal(t, "zero", zero.String())
-	assert.Equal(t, "one", one.String())
-	assert.Equal(t, "multiple", multiple.String())
-	assert.Equal(t, "unsupported", unsupported.String())
-	assert.Equal(t, "unknown(42)", cardinality(42).String())
-}
-
-func TestIsZero(t *testing.T) {
-	var zero int
-	var notZero = 3
-	var nilSlice []int
-	var nonNilSlice = []int{1, 2, 3}
-	var nilMap map[string]string
-	var nonNilMap = map[string]string{"foo": "bar"}
-	var uncomparable = func() {}
-
-	assert.True(t, isZero(reflect.ValueOf(zero)))
-	assert.False(t, isZero(reflect.ValueOf(notZero)))
-
-	assert.True(t, isZero(reflect.ValueOf(nilSlice)))
-	assert.False(t, isZero(reflect.ValueOf(nonNilSlice)))
-
-	assert.True(t, isZero(reflect.ValueOf(nilMap)))
-	assert.False(t, isZero(reflect.ValueOf(nonNilMap)))
-
-	assert.False(t, isZero(reflect.ValueOf(uncomparable)))
-}

sequence_test.go

@@ -1,152 +0,0 @@
-package arg
-
-import (
-	"reflect"
-	"testing"
-
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-)
-
-func TestSetSliceWithoutClearing(t *testing.T) {
-	xs := []int{10}
-	entries := []string{"1", "2", "3"}
-	err := setSlice(reflect.ValueOf(&xs).Elem(), entries, false)
-	require.NoError(t, err)
-	assert.Equal(t, []int{10, 1, 2, 3}, xs)
-}
-
-func TestSetSliceAfterClearing(t *testing.T) {
-	xs := []int{100}
-	entries := []string{"1", "2", "3"}
-	err := setSlice(reflect.ValueOf(&xs).Elem(), entries, true)
-	require.NoError(t, err)
-	assert.Equal(t, []int{1, 2, 3}, xs)
-}
-
-func TestSetSliceInvalid(t *testing.T) {
-	xs := []int{100}
-	entries := []string{"invalid"}
-	err := setSlice(reflect.ValueOf(&xs).Elem(), entries, true)
-	assert.Error(t, err)
-}
-
-func TestSetSlicePtr(t *testing.T) {
-	var xs []*int
-	entries := []string{"1", "2", "3"}
-	err := setSlice(reflect.ValueOf(&xs).Elem(), entries, true)
-	require.NoError(t, err)
-	require.Len(t, xs, 3)
-	assert.Equal(t, 1, *xs[0])
-	assert.Equal(t, 2, *xs[1])
-	assert.Equal(t, 3, *xs[2])
-}
-
-func TestSetSliceTextUnmarshaller(t *testing.T) {
-	// textUnmarshaler is a struct that captures the length of the string passed to it
-	var xs []*textUnmarshaler
-	entries := []string{"a", "aa", "aaa"}
-	err := setSlice(reflect.ValueOf(&xs).Elem(), entries, true)
-	require.NoError(t, err)
-	require.Len(t, xs, 3)
-	assert.Equal(t, 1, xs[0].val)
-	assert.Equal(t, 2, xs[1].val)
-	assert.Equal(t, 3, xs[2].val)
-}
-
-func TestSetMapWithoutClearing(t *testing.T) {
-	m := map[string]int{"foo": 10}
-	entries := []string{"a=1", "b=2"}
-	err := setMap(reflect.ValueOf(&m).Elem(), entries, false)
-	require.NoError(t, err)
-	require.Len(t, m, 3)
-	assert.Equal(t, 1, m["a"])
-	assert.Equal(t, 2, m["b"])
-	assert.Equal(t, 10, m["foo"])
-}
-
-func TestSetMapAfterClearing(t *testing.T) {
-	m := map[string]int{"foo": 10}
-	entries := []string{"a=1", "b=2"}
-	err := setMap(reflect.ValueOf(&m).Elem(), entries, true)
-	require.NoError(t, err)
-	require.Len(t, m, 2)
-	assert.Equal(t, 1, m["a"])
-	assert.Equal(t, 2, m["b"])
-}
-
-func TestSetMapWithKeyPointer(t *testing.T) {
-	// textUnmarshaler is a struct that captures the length of the string passed to it
-	var m map[*string]int
-	entries := []string{"abc=123"}
-	err := setMap(reflect.ValueOf(&m).Elem(), entries, true)
-	require.NoError(t, err)
-	require.Len(t, m, 1)
-}
-
-func TestSetMapWithValuePointer(t *testing.T) {
-	// textUnmarshaler is a struct that captures the length of the string passed to it
-	var m map[string]*int
-	entries := []string{"abc=123"}
-	err := setMap(reflect.ValueOf(&m).Elem(), entries, true)
-	require.NoError(t, err)
-	require.Len(t, m, 1)
-	assert.Equal(t, 123, *m["abc"])
-}
-
-func TestSetMapTextUnmarshaller(t *testing.T) {
-	// textUnmarshaler is a struct that captures the length of the string passed to it
-	var m map[textUnmarshaler]*textUnmarshaler
-	entries := []string{"a=123", "aa=12", "aaa=1"}
-	err := setMap(reflect.ValueOf(&m).Elem(), entries, true)
-	require.NoError(t, err)
-	require.Len(t, m, 3)
-	assert.Equal(t, &textUnmarshaler{3}, m[textUnmarshaler{1}])
-	assert.Equal(t, &textUnmarshaler{2}, m[textUnmarshaler{2}])
-	assert.Equal(t, &textUnmarshaler{1}, m[textUnmarshaler{3}])
-}
-
-func TestSetMapInvalidKey(t *testing.T) {
-	var m map[int]int
-	entries := []string{"invalid=123"}
-	err := setMap(reflect.ValueOf(&m).Elem(), entries, true)
-	assert.Error(t, err)
-}
-
-func TestSetMapInvalidValue(t *testing.T) {
-	var m map[int]int
-	entries := []string{"123=invalid"}
-	err := setMap(reflect.ValueOf(&m).Elem(), entries, true)
-	assert.Error(t, err)
-}
-
-func TestSetMapMalformed(t *testing.T) {
-	// textUnmarshaler is a struct that captures the length of the string passed to it
-	var m map[string]string
-	entries := []string{"missing_equals_sign"}
-	err := setMap(reflect.ValueOf(&m).Elem(), entries, true)
-	assert.Error(t, err)
-}
-
-func TestSetSliceOrMapErrors(t *testing.T) {
-	var err error
-	var dest reflect.Value
-
-	// converting a slice to a reflect.Value in this way will make it read only
-	var cannotSet []int
-	dest = reflect.ValueOf(cannotSet)
-	err = setSliceOrMap(dest, nil, false)
-	assert.Error(t, err)
-
-	// check what happens when we pass in something that is not a slice or a map
-	var notSliceOrMap string
-	dest = reflect.ValueOf(&notSliceOrMap).Elem()
-	err = setSliceOrMap(dest, nil, false)
-	assert.Error(t, err)
-
-	// check what happens when we pass in a pointer to something that is not a slice or a map
-	var stringPtr *string
-	dest = reflect.ValueOf(&stringPtr).Elem()
-	err = setSliceOrMap(dest, nil, false)
-	assert.Error(t, err)
-}

subcommand_test.go

@@ -1,508 +0,0 @@
-package arg
-
-import (
-	"reflect"
-	"testing"
-
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-)
-
-// This file contains tests for parse.go but I decided to put them here
-// since that file is getting large
-
-func TestSubcommandNotAPointer(t *testing.T) {
-	var args struct {
-		A string `arg:"subcommand"`
-	}
-	_, err := NewParser(Config{}, &args)
-	assert.Error(t, err)
-}
-
-func TestSubcommandNotAPointerToStruct(t *testing.T) {
-	var args struct {
-		A struct{} `arg:"subcommand"`
-	}
-	_, err := NewParser(Config{}, &args)
-	assert.Error(t, err)
-}
-
-func TestPositionalAndSubcommandNotAllowed(t *testing.T) {
-	var args struct {
-		A string    `arg:"positional"`
-		B *struct{} `arg:"subcommand"`
-	}
-	_, err := NewParser(Config{}, &args)
-	assert.Error(t, err)
-}
-
-func TestMinimalSubcommand(t *testing.T) {
-	type listCmd struct {
-	}
-	var args struct {
-		List *listCmd `arg:"subcommand"`
-	}
-	p, err := pparse("list", &args)
-	require.NoError(t, err)
-	assert.NotNil(t, args.List)
-	assert.Equal(t, args.List, p.Subcommand())
-	assert.Equal(t, []string{"list"}, p.SubcommandNames())
-}
-
-func TestSubcommandNamesBeforeParsing(t *testing.T) {
-	type listCmd struct{}
-	var args struct {
-		List *listCmd `arg:"subcommand"`
-	}
-	p, err := NewParser(Config{}, &args)
-	require.NoError(t, err)
-	assert.Nil(t, p.Subcommand())
-	assert.Nil(t, p.SubcommandNames())
-}
-
-func TestNoSuchSubcommand(t *testing.T) {
-	type listCmd struct {
-	}
-	var args struct {
-		List *listCmd `arg:"subcommand"`
-	}
-	_, err := pparse("invalid", &args)
-	assert.Error(t, err)
-}
-
-func TestNamedSubcommand(t *testing.T) {
-	type listCmd struct {
-	}
-	var args struct {
-		List *listCmd `arg:"subcommand:ls"`
-	}
-	p, err := pparse("ls", &args)
-	require.NoError(t, err)
-	assert.NotNil(t, args.List)
-	assert.Equal(t, args.List, p.Subcommand())
-	assert.Equal(t, []string{"ls"}, p.SubcommandNames())
-}
-
-func TestSubcommandAliases(t *testing.T) {
-	type listCmd struct {
-	}
-	var args struct {
-		List *listCmd `arg:"subcommand:list|ls"`
-	}
-	p, err := pparse("ls", &args)
-	require.NoError(t, err)
-	assert.NotNil(t, args.List)
-	assert.Equal(t, args.List, p.Subcommand())
-	assert.Equal(t, []string{"ls"}, p.SubcommandNames())
-}
-
-func TestEmptySubcommand(t *testing.T) {
-	type listCmd struct {
-	}
-	var args struct {
-		List *listCmd `arg:"subcommand"`
-	}
-	p, err := pparse("", &args)
-	require.NoError(t, err)
-	assert.Nil(t, args.List)
-	assert.Nil(t, p.Subcommand())
-	assert.Empty(t, p.SubcommandNames())
-}
-
-func TestTwoSubcommands(t *testing.T) {
-	type getCmd struct {
-	}
-	type listCmd struct {
-	}
-	var args struct {
-		Get  *getCmd  `arg:"subcommand"`
-		List *listCmd `arg:"subcommand"`
-	}
-	p, err := pparse("list", &args)
-	require.NoError(t, err)
-	assert.Nil(t, args.Get)
-	assert.NotNil(t, args.List)
-	assert.Equal(t, args.List, p.Subcommand())
-	assert.Equal(t, []string{"list"}, p.SubcommandNames())
-}
-
-func TestTwoSubcommandsWithAliases(t *testing.T) {
-	type getCmd struct {
-	}
-	type listCmd struct {
-	}
-	var args struct {
-		Get  *getCmd  `arg:"subcommand:get|g"`
-		List *listCmd `arg:"subcommand:list|ls"`
-	}
-	p, err := pparse("ls", &args)
-	require.NoError(t, err)
-	assert.Nil(t, args.Get)
-	assert.NotNil(t, args.List)
-	assert.Equal(t, args.List, p.Subcommand())
-	assert.Equal(t, []string{"ls"}, p.SubcommandNames())
-}
-
-func TestSubcommandsWithOptions(t *testing.T) {
-	type getCmd struct {
-		Name string
-	}
-	type listCmd struct {
-		Limit int
-	}
-	type cmd struct {
-		Verbose bool
-		Get     *getCmd  `arg:"subcommand"`
-		List    *listCmd `arg:"subcommand"`
-	}
-
-	{
-		var args cmd
-		err := parse("list", &args)
-		require.NoError(t, err)
-		assert.Nil(t, args.Get)
-		assert.NotNil(t, args.List)
-	}
-
-	{
-		var args cmd
-		err := parse("list --limit 3", &args)
-		require.NoError(t, err)
-		assert.Nil(t, args.Get)
-		assert.NotNil(t, args.List)
-		assert.Equal(t, args.List.Limit, 3)
-	}
-
-	{
-		var args cmd
-		err := parse("list --limit 3 --verbose", &args)
-		require.NoError(t, err)
-		assert.Nil(t, args.Get)
-		assert.NotNil(t, args.List)
-		assert.Equal(t, args.List.Limit, 3)
-		assert.True(t, args.Verbose)
-	}
-
-	{
-		var args cmd
-		err := parse("list --verbose --limit 3", &args)
-		require.NoError(t, err)
-		assert.Nil(t, args.Get)
-		assert.NotNil(t, args.List)
-		assert.Equal(t, args.List.Limit, 3)
-		assert.True(t, args.Verbose)
-	}
-
-	{
-		var args cmd
-		err := parse("--verbose list --limit 3", &args)
-		require.NoError(t, err)
-		assert.Nil(t, args.Get)
-		assert.NotNil(t, args.List)
-		assert.Equal(t, args.List.Limit, 3)
-		assert.True(t, args.Verbose)
-	}
-
-	{
-		var args cmd
-		err := parse("get", &args)
-		require.NoError(t, err)
-		assert.NotNil(t, args.Get)
-		assert.Nil(t, args.List)
-	}
-
-	{
-		var args cmd
-		err := parse("get --name test", &args)
-		require.NoError(t, err)
-		assert.NotNil(t, args.Get)
-		assert.Nil(t, args.List)
-		assert.Equal(t, args.Get.Name, "test")
-	}
-}
-
-func TestSubcommandsWithEnvVars(t *testing.T) {
-	type getCmd struct {
-		Name string `arg:"env"`
-	}
-	type listCmd struct {
-		Limit int `arg:"env"`
-	}
-	type cmd struct {
-		Verbose bool
-		Get     *getCmd  `arg:"subcommand"`
-		List    *listCmd `arg:"subcommand"`
-	}
-
-	{
-		var args cmd
-		setenv(t, "LIMIT", "123")
-		err := parse("list", &args)
-		require.NoError(t, err)
-		require.NotNil(t, args.List)
-		assert.Equal(t, 123, args.List.Limit)
-	}
-
-	{
-		var args cmd
-		setenv(t, "LIMIT", "not_an_integer")
-		err := parse("list", &args)
-		assert.Error(t, err)
-	}
-}
-
-func TestNestedSubcommands(t *testing.T) {
-	type child struct{}
-	type parent struct {
-		Child *child `arg:"subcommand"`
-	}
-	type grandparent struct {
-		Parent *parent `arg:"subcommand"`
-	}
-	type root struct {
-		Grandparent *grandparent `arg:"subcommand"`
-	}
-
-	{
-		var args root
-		p, err := pparse("grandparent parent child", &args)
-		require.NoError(t, err)
-		require.NotNil(t, args.Grandparent)
-		require.NotNil(t, args.Grandparent.Parent)
-		require.NotNil(t, args.Grandparent.Parent.Child)
-		assert.Equal(t, args.Grandparent.Parent.Child, p.Subcommand())
-		assert.Equal(t, []string{"grandparent", "parent", "child"}, p.SubcommandNames())
-	}
-
-	{
-		var args root
-		p, err := pparse("grandparent parent", &args)
-		require.NoError(t, err)
-		require.NotNil(t, args.Grandparent)
-		require.NotNil(t, args.Grandparent.Parent)
-		require.Nil(t, args.Grandparent.Parent.Child)
-		assert.Equal(t, args.Grandparent.Parent, p.Subcommand())
-		assert.Equal(t, []string{"grandparent", "parent"}, p.SubcommandNames())
-	}
-
-	{
-		var args root
-		p, err := pparse("grandparent", &args)
-		require.NoError(t, err)
-		require.NotNil(t, args.Grandparent)
-		require.Nil(t, args.Grandparent.Parent)
-		assert.Equal(t, args.Grandparent, p.Subcommand())
-		assert.Equal(t, []string{"grandparent"}, p.SubcommandNames())
-	}
-
-	{
-		var args root
-		p, err := pparse("", &args)
-		require.NoError(t, err)
-		require.Nil(t, args.Grandparent)
-		assert.Nil(t, p.Subcommand())
-		assert.Empty(t, p.SubcommandNames())
-	}
-}
-
-func TestNestedSubcommandsWithAliases(t *testing.T) {
-	type child struct{}
-	type parent struct {
-		Child *child `arg:"subcommand:child|ch"`
-	}
-	type grandparent struct {
-		Parent *parent `arg:"subcommand:parent|pa"`
-	}
-	type root struct {
-		Grandparent *grandparent `arg:"subcommand:grandparent|gp"`
-	}
-
-	{
-		var args root
-		p, err := pparse("gp parent child", &args)
-		require.NoError(t, err)
-		require.NotNil(t, args.Grandparent)
-		require.NotNil(t, args.Grandparent.Parent)
-		require.NotNil(t, args.Grandparent.Parent.Child)
-		assert.Equal(t, args.Grandparent.Parent.Child, p.Subcommand())
-		assert.Equal(t, []string{"gp", "parent", "child"}, p.SubcommandNames())
-	}
-
-	{
-		var args root
-		p, err := pparse("grandparent pa", &args)
-		require.NoError(t, err)
-		require.NotNil(t, args.Grandparent)
-		require.NotNil(t, args.Grandparent.Parent)
-		require.Nil(t, args.Grandparent.Parent.Child)
-		assert.Equal(t, args.Grandparent.Parent, p.Subcommand())
-		assert.Equal(t, []string{"grandparent", "pa"}, p.SubcommandNames())
-	}
-
-	{
-		var args root
-		p, err := pparse("grandparent", &args)
-		require.NoError(t, err)
-		require.NotNil(t, args.Grandparent)
-		require.Nil(t, args.Grandparent.Parent)
-		assert.Equal(t, args.Grandparent, p.Subcommand())
-		assert.Equal(t, []string{"grandparent"}, p.SubcommandNames())
-	}
-
-	{
-		var args root
-		p, err := pparse("", &args)
-		require.NoError(t, err)
-		require.Nil(t, args.Grandparent)
-		assert.Nil(t, p.Subcommand())
-		assert.Empty(t, p.SubcommandNames())
-	}
-}
-
-func TestSubcommandsWithPositionals(t *testing.T) {
-	type listCmd struct {
-		Pattern string `arg:"positional"`
-	}
-	type cmd struct {
-		Format string
-		List   *listCmd `arg:"subcommand"`
-	}
-
-	{
-		var args cmd
-		err := parse("list", &args)
-		require.NoError(t, err)
-		assert.NotNil(t, args.List)
-		assert.Equal(t, "", args.List.Pattern)
-	}
-
-	{
-		var args cmd
-		err := parse("list --format json", &args)
-		require.NoError(t, err)
-		assert.NotNil(t, args.List)
-		assert.Equal(t, "", args.List.Pattern)
-		assert.Equal(t, "json", args.Format)
-	}
-
-	{
-		var args cmd
-		err := parse("list somepattern", &args)
-		require.NoError(t, err)
-		assert.NotNil(t, args.List)
-		assert.Equal(t, "somepattern", args.List.Pattern)
-	}
-
-	{
-		var args cmd
-		err := parse("list somepattern --format json", &args)
-		require.NoError(t, err)
-		assert.NotNil(t, args.List)
-		assert.Equal(t, "somepattern", args.List.Pattern)
-		assert.Equal(t, "json", args.Format)
-	}
-
-	{
-		var args cmd
-		err := parse("list --format json somepattern", &args)
-		require.NoError(t, err)
-		assert.NotNil(t, args.List)
-		assert.Equal(t, "somepattern", args.List.Pattern)
-		assert.Equal(t, "json", args.Format)
-	}
-
-	{
-		var args cmd
-		err := parse("--format json list somepattern", &args)
-		require.NoError(t, err)
-		assert.NotNil(t, args.List)
-		assert.Equal(t, "somepattern", args.List.Pattern)
-		assert.Equal(t, "json", args.Format)
-	}
-
-	{
-		var args cmd
-		err := parse("--format json", &args)
-		require.NoError(t, err)
-		assert.Nil(t, args.List)
-		assert.Equal(t, "json", args.Format)
-	}
-}
-func TestSubcommandsWithMultiplePositionals(t *testing.T) {
-	type getCmd struct {
-		Items []string `arg:"positional"`
-	}
-	type cmd struct {
-		Limit int
-		Get   *getCmd `arg:"subcommand"`
-	}
-
-	{
-		var args cmd
-		err := parse("get", &args)
-		require.NoError(t, err)
-		assert.NotNil(t, args.Get)
-		assert.Empty(t, args.Get.Items)
-	}
-
-	{
-		var args cmd
-		err := parse("get --limit 5", &args)
-		require.NoError(t, err)
-		assert.NotNil(t, args.Get)
-		assert.Empty(t, args.Get.Items)
-		assert.Equal(t, 5, args.Limit)
-	}
-
-	{
-		var args cmd
-		err := parse("get item1", &args)
-		require.NoError(t, err)
-		assert.NotNil(t, args.Get)
-		assert.Equal(t, []string{"item1"}, args.Get.Items)
-	}
-
-	{
-		var args cmd
-		err := parse("get item1 item2 item3", &args)
-		require.NoError(t, err)
-		assert.NotNil(t, args.Get)
-		assert.Equal(t, []string{"item1", "item2", "item3"}, args.Get.Items)
-	}
-
-	{
-		var args cmd
-		err := parse("get item1 --limit 5 item2", &args)
-		require.NoError(t, err)
-		assert.NotNil(t, args.Get)
-		assert.Equal(t, []string{"item1", "item2"}, args.Get.Items)
-		assert.Equal(t, 5, args.Limit)
-	}
-}
-
-func TestValForNilStruct(t *testing.T) {
-	type subcmd struct{}
-	var cmd struct {
-		Sub *subcmd `arg:"subcommand"`
-	}
-
-	p, err := NewParser(Config{}, &cmd)
-	require.NoError(t, err)
-
-	typ := reflect.TypeOf(cmd)
-	subField, _ := typ.FieldByName("Sub")
-
-	v := p.val(path{fields: []reflect.StructField{subField, subField}})
-	assert.False(t, v.IsValid())
-}
-
-func TestSubcommandInvalidInternal(t *testing.T) {
-	// this situation should never arise in practice but still good to test for it
-	var cmd struct{}
-	p, err := NewParser(Config{}, &cmd)
-	require.NoError(t, err)
-
-	p.subcommand = []string{"should", "never", "happen"}
-	sub := p.Subcommand()
-	assert.Nil(t, sub)
-}

usage_test.go

@@ -1,717 +0,0 @@
-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()))
-}
-
-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 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 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, -1, 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, -1, 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())
-}