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mirror of https://github.com/prometheus-community/postgres_exporter.git synced 2025-08-08 04:42:07 +03:00

Add self-contained gometalinter build tooling.

This commit is contained in:
Will Rouesnel
2017-06-06 21:39:41 +10:00
parent 0de0311c22
commit e2b6c973a1
710 changed files with 277204 additions and 35 deletions

24
tools/vendor/github.com/alexflint/go-arg/LICENSE generated vendored Normal file
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Copyright (c) 2015, Alex Flint
All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:
* Redistributions of source code must retain the above copyright notice, this
list of conditions and the following disclaimer.
* Redistributions in binary form must reproduce the above copyright notice,
this list of conditions and the following disclaimer in the documentation
and/or other materials provided with the distribution.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

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[![GoDoc](https://godoc.org/github.com/alexflint/go-arg?status.svg)](https://godoc.org/github.com/alexflint/go-arg)
[![Build Status](https://travis-ci.org/alexflint/go-arg.svg?branch=master)](https://travis-ci.org/alexflint/go-arg)
[![Coverage Status](https://coveralls.io/repos/alexflint/go-arg/badge.svg?branch=master&service=github)](https://coveralls.io/github/alexflint/go-arg?branch=master)
[![Report Card](https://goreportcard.com/badge/github.com/alexflint/go-arg)](https://goreportcard.com/badge/github.com/alexflint/go-arg)
## Structured argument parsing for Go
```shell
go get github.com/alexflint/go-arg
```
Declare the command line arguments your program accepts by defining a struct.
```go
var args struct {
Foo string
Bar bool
}
arg.MustParse(&args)
fmt.Println(args.Foo, args.Bar)
```
```shell
$ ./example --foo=hello --bar
hello true
```
### Required arguments
```go
var args struct {
ID int `arg:"required"`
Timeout time.Duration
}
arg.MustParse(&args)
```
```shell
$ ./example
Usage: example --id ID [--timeout TIMEOUT]
error: --id is required
```
### Positional arguments
```go
var args struct {
Input string `arg:"positional"`
Output []string `arg:"positional"`
}
arg.MustParse(&args)
fmt.Println("Input:", args.Input)
fmt.Println("Output:", args.Output)
```
```
$ ./example src.txt x.out y.out z.out
Input: src.txt
Output: [x.out y.out z.out]
```
### Environment variables
```go
var args struct {
Workers int `arg:"env"`
}
arg.MustParse(&args)
fmt.Println("Workers:", args.Workers)
```
```
$ WORKERS=4 ./example
Workers: 4
```
```
$ WORKERS=4 ./example --workers=6
Workers: 6
```
You can also override the name of the environment variable:
```go
var args struct {
Workers int `arg:"env:NUM_WORKERS"`
}
arg.MustParse(&args)
fmt.Println("Workers:", args.Workers)
```
```
$ NUM_WORKERS=4 ./example
Workers: 4
```
### Usage strings
```go
var args struct {
Input string `arg:"positional"`
Output []string `arg:"positional"`
Verbose bool `arg:"-v,help:verbosity level"`
Dataset string `arg:"help:dataset to use"`
Optimize int `arg:"-O,help:optimization level"`
}
arg.MustParse(&args)
```
```shell
$ ./example -h
Usage: [--verbose] [--dataset DATASET] [--optimize OPTIMIZE] [--help] INPUT [OUTPUT [OUTPUT ...]]
Positional arguments:
INPUT
OUTPUT
Options:
--verbose, -v verbosity level
--dataset DATASET dataset to use
--optimize OPTIMIZE, -O OPTIMIZE
optimization level
--help, -h print this help message
```
### Default values
```go
var args struct {
Foo string
Bar bool
}
args.Foo = "default value"
arg.MustParse(&args)
```
### Arguments with multiple values
```go
var args struct {
Database string
IDs []int64
}
arg.MustParse(&args)
fmt.Printf("Fetching the following IDs from %s: %q", args.Database, args.IDs)
```
```shell
./example -database foo -ids 1 2 3
Fetching the following IDs from foo: [1 2 3]
```
### Arguments that can be specified multiple times, mixed with positionals
```go
var args struct {
Commands []string `arg:"-c,separate"`
Files []string `arg:"-f,separate"`
Databases []string `arg:"positional"`
}
```
```shell
./example -c cmd1 db1 -f file1 db2 -c cmd2 -f file2 -f file3 db3 -c cmd3
Commands: [cmd1 cmd2 cmd3]
Files [file1 file2 file3]
Databases [db1 db2 db3]
```
### Custom validation
```go
var args struct {
Foo string
Bar string
}
p := arg.MustParse(&args)
if args.Foo == "" && args.Bar == "" {
p.Fail("you must provide one of --foo and --bar")
}
```
```shell
./example
Usage: samples [--foo FOO] [--bar BAR]
error: you must provide one of --foo and --bar
```
### Version strings
```go
type args struct {
...
}
func (args) Version() string {
return "someprogram 4.3.0"
}
func main() {
var args args
arg.MustParse(&args)
}
```
```shell
$ ./example --version
someprogram 4.3.0
```
### Embedded structs
The fields of embedded structs are treated just like regular fields:
```go
type DatabaseOptions struct {
Host string
Username string
Password string
}
type LogOptions struct {
LogFile string
Verbose bool
}
func main() {
var args struct {
DatabaseOptions
LogOptions
}
arg.MustParse(&args)
}
```
As usual, any field tagged with `arg:"-"` is ignored.
### Custom parsing
You can implement your own argument parser by implementing `encoding.TextUnmarshaler`:
```go
package main
import (
"fmt"
"strings"
"github.com/alexflint/go-arg"
)
// Accepts command line arguments of the form "head.tail"
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 main() {
var args struct {
Name *NameDotName
}
arg.MustParse(&args)
fmt.Printf("%#v\n", args.Name)
}
```
```shell
$ ./example --name=foo.bar
&main.NameDotName{Head:"foo", Tail:"bar"}
$ ./example --name=oops
Usage: example [--name NAME]
error: error processing --name: missing period in "oops"
```
### Description strings
```go
type args struct {
Foo string
}
func (args) Description() string {
return "this program does this and that"
}
func main() {
var args args
arg.MustParse(&args)
}
```
```shell
$ ./example -h
this program does this and that
Usage: example [--foo FOO]
Options:
--foo FOO
--help, -h display this help and exit
```
### Documentation
https://godoc.org/github.com/alexflint/go-arg
### Rationale
There are many command line argument parsing libraries for Go, including one in the standard library, so why build another?
The shortcomings of the `flag` library that ships in the standard library are well known. Positional arguments must preceed options, so `./prog x --foo=1` does what you expect but `./prog --foo=1 x` does not. Arguments cannot have both long (`--foo`) and short (`-f`) forms.
Many third-party argument parsing libraries are geared for writing sophisticated command line interfaces. The excellent `codegangsta/cli` is perfect for working with multiple sub-commands and nested flags, but is probably overkill for a simple script with a handful of flags.
The main idea behind `go-arg` is that Go already has an excellent way to describe data structures using Go structs, so there is no need to develop more levels of abstraction on top of this. Instead of one API to specify which arguments your program accepts, and then another API to get the values of those arguments, why not replace both with a single struct?

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// Package arg parses command line arguments using the fields from a struct.
//
// For example,
//
// var args struct {
// Iter int
// Debug bool
// }
// arg.MustParse(&args)
//
// defines two command line arguments, which can be set using any of
//
// ./example --iter=1 --debug // debug is a boolean flag so its value is set to true
// ./example -iter 1 // debug defaults to its zero value (false)
// ./example --debug=true // iter defaults to its zero value (zero)
//
// The fastest way to see how to use go-arg is to read the examples below.
//
// Fields can be bool, string, any float type, or any signed or unsigned integer type.
// They can also be slices of any of the above, or slices of pointers to any of the above.
//
// Tags can be specified using the `arg` package name:
//
// var args struct {
// Input string `arg:"positional"`
// Log string `arg:"positional,required"`
// Debug bool `arg:"-d,help:turn on debug mode"`
// RealMode bool `arg:"--real"
// Wr io.Writer `arg:"-"`
// }
//
// The valid tag strings are `positional`, `required`, and `help`. Further, any tag string
// that starts with a single hyphen is the short form for an argument (e.g. `./example -d`),
// and any tag string that starts with two hyphens is the long form for the argument
// (instead of the field name). Fields can be excluded from processing with `arg:"-"`.
package arg

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package arg
import (
"encoding"
"errors"
"fmt"
"os"
"path/filepath"
"reflect"
"strings"
scalar "github.com/alexflint/go-scalar"
)
// spec represents a command line option
type spec struct {
dest reflect.Value
long string
short string
multiple bool
required bool
positional bool
separate bool
help string
env string
wasPresent bool
boolean bool
}
// ErrHelp indicates that -h or --help were provided
var ErrHelp = errors.New("help requested by user")
// ErrVersion indicates that --version was provided
var ErrVersion = errors.New("version requested by user")
// MustParse processes command line arguments and exits upon failure
func MustParse(dest ...interface{}) *Parser {
p, err := NewParser(Config{}, dest...)
if err != nil {
fmt.Println(err)
os.Exit(-1)
}
err = p.Parse(flags())
if err == ErrHelp {
p.WriteHelp(os.Stdout)
os.Exit(0)
}
if err == ErrVersion {
fmt.Println(p.version)
os.Exit(0)
}
if err != nil {
p.Fail(err.Error())
}
return p
}
// Parse processes command line arguments and stores them in dest
func Parse(dest ...interface{}) error {
p, err := NewParser(Config{}, dest...)
if err != nil {
return err
}
return p.Parse(flags())
}
// flags gets all command line arguments other than the first (program name)
func flags() []string {
if len(os.Args) == 0 { // os.Args could be empty
return nil
}
return os.Args[1:]
}
// Config represents configuration options for an argument parser
type Config struct {
Program string // Program is the name of the program used in the help text
}
// Parser represents a set of command line options with destination values
type Parser struct {
spec []*spec
config Config
version string
description string
}
// Versioned is the interface that the destination struct should implement to
// make a version string appear at the top of the help message.
type Versioned interface {
// Version returns the version string that will be printed on a line by itself
// at the top of the help message.
Version() string
}
// Described is the interface that the destination struct should implement to
// make a description string appear at the top of the help message.
type Described interface {
// Description returns the string that will be printed on a line by itself
// at the top of the help message.
Description() string
}
// walkFields calls a function for each field of a struct, recursively expanding struct fields.
func walkFields(v reflect.Value, visit func(field reflect.StructField, val reflect.Value, owner reflect.Type) bool) {
t := v.Type()
for i := 0; i < t.NumField(); i++ {
field := t.Field(i)
val := v.Field(i)
expand := visit(field, val, t)
if expand && field.Type.Kind() == reflect.Struct {
walkFields(val, visit)
}
}
}
// NewParser constructs a parser from a list of destination structs
func NewParser(config Config, dests ...interface{}) (*Parser, error) {
p := Parser{
config: config,
}
for _, dest := range dests {
if dest, ok := dest.(Versioned); ok {
p.version = dest.Version()
}
if dest, ok := dest.(Described); ok {
p.description = dest.Description()
}
v := reflect.ValueOf(dest)
if v.Kind() != reflect.Ptr {
panic(fmt.Sprintf("%s is not a pointer (did you forget an ampersand?)", v.Type()))
}
v = v.Elem()
if v.Kind() != reflect.Struct {
panic(fmt.Sprintf("%T is not a struct pointer", dest))
}
var errs []string
walkFields(v, func(field reflect.StructField, val reflect.Value, t reflect.Type) bool {
// Check for the ignore switch in the tag
tag := field.Tag.Get("arg")
if tag == "-" {
return false
}
// If this is an embedded struct then recurse into its fields
if field.Anonymous && field.Type.Kind() == reflect.Struct {
return true
}
spec := spec{
long: strings.ToLower(field.Name),
dest: val,
}
// Check whether this field is supported. It's good to do this here rather than
// wait until setScalar because it means that a program with invalid argument
// fields will always fail regardless of whether the arguments it received
// exercised those fields.
var parseable bool
parseable, spec.boolean, spec.multiple = canParse(field.Type)
if !parseable {
errs = append(errs, fmt.Sprintf("%s.%s: %s fields are not supported",
t.Name(), field.Name, field.Type.String()))
return false
}
// Look at the tag
if tag != "" {
for _, key := range strings.Split(tag, ",") {
var value string
if pos := strings.Index(key, ":"); pos != -1 {
value = key[pos+1:]
key = key[:pos]
}
switch {
case strings.HasPrefix(key, "---"):
errs = append(errs, fmt.Sprintf("%s.%s: too many hyphens", t.Name(), field.Name))
case strings.HasPrefix(key, "--"):
spec.long = key[2:]
case strings.HasPrefix(key, "-"):
if len(key) != 2 {
errs = append(errs, fmt.Sprintf("%s.%s: short arguments must be one character only",
t.Name(), field.Name))
return false
}
spec.short = key[1:]
case key == "required":
spec.required = true
case key == "positional":
spec.positional = true
case key == "separate":
spec.separate = true
case key == "help":
spec.help = value
case key == "env":
// Use override name if provided
if value != "" {
spec.env = value
} else {
spec.env = strings.ToUpper(field.Name)
}
default:
errs = append(errs, fmt.Sprintf("unrecognized tag '%s' on field %s", key, tag))
return false
}
}
}
p.spec = append(p.spec, &spec)
// if this was an embedded field then we already returned true up above
return false
})
if len(errs) > 0 {
return nil, errors.New(strings.Join(errs, "\n"))
}
}
if p.config.Program == "" {
p.config.Program = "program"
if len(os.Args) > 0 {
p.config.Program = filepath.Base(os.Args[0])
}
}
return &p, nil
}
// Parse processes the given command line option, storing the results in the field
// of the structs from which NewParser was constructed
func (p *Parser) Parse(args []string) error {
// If -h or --help were specified then print usage
for _, arg := range args {
if arg == "-h" || arg == "--help" {
return ErrHelp
}
if arg == "--version" {
return ErrVersion
}
if arg == "--" {
break
}
}
// Process all command line arguments
err := process(p.spec, args)
if err != nil {
return err
}
// Validate
return validate(p.spec)
}
// process goes through arguments one-by-one, parses them, and assigns the result to
// the underlying struct field
func process(specs []*spec, args []string) error {
// construct a map from --option to spec
optionMap := make(map[string]*spec)
for _, spec := range specs {
if spec.positional {
continue
}
if spec.long != "" {
optionMap[spec.long] = spec
}
if spec.short != "" {
optionMap[spec.short] = spec
}
if spec.env != "" {
if value, found := os.LookupEnv(spec.env); found {
err := setScalar(spec.dest, value)
if err != nil {
return fmt.Errorf("error processing environment variable %s: %v", spec.env, err)
}
spec.wasPresent = true
}
}
}
// process each string from the command line
var allpositional bool
var positionals []string
// must use explicit for loop, not range, because we manipulate i inside the loop
for i := 0; i < len(args); i++ {
arg := args[i]
if arg == "--" {
allpositional = true
continue
}
if !isFlag(arg) || allpositional {
positionals = append(positionals, arg)
continue
}
// check for an equals sign, as in "--foo=bar"
var value string
opt := strings.TrimLeft(arg, "-")
if pos := strings.Index(opt, "="); pos != -1 {
value = opt[pos+1:]
opt = opt[:pos]
}
// lookup the spec for this option
spec, ok := optionMap[opt]
if !ok {
return fmt.Errorf("unknown argument %s", arg)
}
spec.wasPresent = true
// deal with the case of multiple values
if spec.multiple {
var values []string
if value == "" {
for i+1 < len(args) && !isFlag(args[i+1]) {
values = append(values, args[i+1])
i++
if spec.separate {
break
}
}
} else {
values = append(values, value)
}
err := setSlice(spec.dest, values, !spec.separate)
if err != nil {
return fmt.Errorf("error processing %s: %v", arg, err)
}
continue
}
// if it's a flag and it has no value then set the value to true
// use boolean because this takes account of TextUnmarshaler
if spec.boolean && value == "" {
value = "true"
}
// if we have something like "--foo" then the value is the next argument
if value == "" {
if i+1 == len(args) || isFlag(args[i+1]) {
return fmt.Errorf("missing value for %s", arg)
}
value = args[i+1]
i++
}
err := setScalar(spec.dest, value)
if err != nil {
return fmt.Errorf("error processing %s: %v", arg, err)
}
}
// process positionals
for _, spec := range specs {
if spec.positional {
if spec.multiple {
if spec.required && len(positionals) == 0 {
return fmt.Errorf("%s is required", spec.long)
}
err := setSlice(spec.dest, positionals, true)
if err != nil {
return fmt.Errorf("error processing %s: %v", spec.long, err)
}
positionals = nil
} else if len(positionals) > 0 {
err := setScalar(spec.dest, positionals[0])
if err != nil {
return fmt.Errorf("error processing %s: %v", spec.long, err)
}
positionals = positionals[1:]
} else if spec.required {
return fmt.Errorf("%s is required", spec.long)
}
}
}
if len(positionals) > 0 {
return fmt.Errorf("too many positional arguments at '%s'", positionals[0])
}
return nil
}
// isFlag returns true if a token is a flag such as "-v" or "--user" but not "-" or "--"
func isFlag(s string) bool {
return strings.HasPrefix(s, "-") && strings.TrimLeft(s, "-") != ""
}
// validate an argument spec after arguments have been parse
func validate(spec []*spec) error {
for _, arg := range spec {
if !arg.positional && arg.required && !arg.wasPresent {
return fmt.Errorf("--%s is required", arg.long)
}
}
return nil
}
// parse a value as the appropriate type and store it in the struct
func setSlice(dest reflect.Value, values []string, trunc bool) error {
if !dest.CanSet() {
return fmt.Errorf("field is not writable")
}
var ptr bool
elem := dest.Type().Elem()
if elem.Kind() == reflect.Ptr {
ptr = true
elem = elem.Elem()
}
// Truncate the dest slice in case default values exist
if trunc && !dest.IsNil() {
dest.SetLen(0)
}
for _, s := range values {
v := reflect.New(elem)
if err := setScalar(v.Elem(), s); err != nil {
return err
}
if !ptr {
v = v.Elem()
}
dest.Set(reflect.Append(dest, v))
}
return nil
}
// canParse returns true if the type can be parsed from a string
func canParse(t reflect.Type) (parseable, boolean, multiple bool) {
parseable, boolean = isScalar(t)
if parseable {
return
}
// Look inside pointer types
if t.Kind() == reflect.Ptr {
t = t.Elem()
}
// Look inside slice types
if t.Kind() == reflect.Slice {
multiple = true
t = t.Elem()
}
parseable, boolean = isScalar(t)
if parseable {
return
}
// Look inside pointer types (again, in case of []*Type)
if t.Kind() == reflect.Ptr {
t = t.Elem()
}
parseable, boolean = isScalar(t)
if parseable {
return
}
return false, false, false
}
var textUnmarshalerType = reflect.TypeOf([]encoding.TextUnmarshaler{}).Elem()
// isScalar returns true if the type can be parsed from a single string
func isScalar(t reflect.Type) (parseable, boolean bool) {
parseable = scalar.CanParse(t)
switch {
case t.Implements(textUnmarshalerType):
return parseable, false
case t.Kind() == reflect.Bool:
return parseable, true
case t.Kind() == reflect.Ptr && t.Elem().Kind() == reflect.Bool:
return parseable, true
default:
return parseable, false
}
}
// set a value from a string
func setScalar(v reflect.Value, s string) error {
return scalar.ParseValue(v, s)
}

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package arg
import (
"fmt"
"io"
"os"
"reflect"
"strings"
)
// the width of the left column
const colWidth = 25
// Fail prints usage information to stderr and exits with non-zero status
func (p *Parser) Fail(msg string) {
p.WriteUsage(os.Stderr)
fmt.Fprintln(os.Stderr, "error:", msg)
os.Exit(-1)
}
// WriteUsage writes usage information to the given writer
func (p *Parser) WriteUsage(w io.Writer) {
var positionals, options []*spec
for _, spec := range p.spec {
if spec.positional {
positionals = append(positionals, spec)
} else {
options = append(options, spec)
}
}
if p.version != "" {
fmt.Fprintln(w, p.version)
}
fmt.Fprintf(w, "Usage: %s", p.config.Program)
// write the option component of the usage message
for _, spec := range options {
// prefix with a space
fmt.Fprint(w, " ")
if !spec.required {
fmt.Fprint(w, "[")
}
fmt.Fprint(w, synopsis(spec, "--"+spec.long))
if !spec.required {
fmt.Fprint(w, "]")
}
}
// write the positional component of the usage message
for _, spec := range positionals {
// prefix with a space
fmt.Fprint(w, " ")
up := strings.ToUpper(spec.long)
if spec.multiple {
if !spec.required {
fmt.Fprint(w, "[")
}
fmt.Fprintf(w, "%s [%s ...]", up, up)
if !spec.required {
fmt.Fprint(w, "]")
}
} else {
fmt.Fprint(w, up)
}
}
fmt.Fprint(w, "\n")
}
// WriteHelp writes the usage string followed by the full help string for each option
func (p *Parser) WriteHelp(w io.Writer) {
var positionals, options []*spec
for _, spec := range p.spec {
if spec.positional {
positionals = append(positionals, spec)
} else {
options = append(options, spec)
}
}
if p.description != "" {
fmt.Fprintln(w, p.description)
}
p.WriteUsage(w)
// write the list of positionals
if len(positionals) > 0 {
fmt.Fprint(w, "\nPositional arguments:\n")
for _, spec := range positionals {
left := " " + strings.ToUpper(spec.long)
fmt.Fprint(w, left)
if spec.help != "" {
if len(left)+2 < colWidth {
fmt.Fprint(w, strings.Repeat(" ", colWidth-len(left)))
} else {
fmt.Fprint(w, "\n"+strings.Repeat(" ", colWidth))
}
fmt.Fprint(w, spec.help)
}
fmt.Fprint(w, "\n")
}
}
// write the list of options
fmt.Fprint(w, "\nOptions:\n")
for _, spec := range options {
printOption(w, spec)
}
// write the list of built in options
printOption(w, &spec{boolean: true, long: "help", short: "h", help: "display this help and exit"})
if p.version != "" {
printOption(w, &spec{boolean: true, long: "version", help: "display version and exit"})
}
}
func printOption(w io.Writer, spec *spec) {
left := " " + synopsis(spec, "--"+spec.long)
if spec.short != "" {
left += ", " + synopsis(spec, "-"+spec.short)
}
fmt.Fprint(w, left)
if spec.help != "" {
if len(left)+2 < colWidth {
fmt.Fprint(w, strings.Repeat(" ", colWidth-len(left)))
} else {
fmt.Fprint(w, "\n"+strings.Repeat(" ", colWidth))
}
fmt.Fprint(w, spec.help)
}
// If spec.dest is not the zero value then a default value has been added.
v := spec.dest
if v.IsValid() {
z := reflect.Zero(v.Type())
if (v.Type().Comparable() && z.Type().Comparable() && v.Interface() != z.Interface()) || v.Kind() == reflect.Slice && !v.IsNil() {
fmt.Fprintf(w, " [default: %v]", v)
}
}
fmt.Fprint(w, "\n")
}
func synopsis(spec *spec, form string) string {
if spec.boolean {
return form
}
return form + " " + strings.ToUpper(spec.long)
}