mirror of
https://github.com/cheat/cheat.git
synced 2024-11-24 06:51:36 +01:00
576 lines
15 KiB
Go
576 lines
15 KiB
Go
// Licensed under terms of MIT license (see LICENSE-MIT)
|
|
// Copyright (c) 2013 Keith Batten, kbatten@gmail.com
|
|
// Copyright (c) 2016 David Irvine
|
|
|
|
package docopt
|
|
|
|
import (
|
|
"fmt"
|
|
"os"
|
|
"regexp"
|
|
"strings"
|
|
)
|
|
|
|
type Parser struct {
|
|
// HelpHandler is called when we encounter bad user input, or when the user
|
|
// asks for help.
|
|
// By default, this calls os.Exit(0) if it handled a built-in option such
|
|
// as -h, --help or --version. If the user errored with a wrong command or
|
|
// options, we exit with a return code of 1.
|
|
HelpHandler func(err error, usage string)
|
|
// OptionsFirst requires that option flags always come before positional
|
|
// arguments; otherwise they can overlap.
|
|
OptionsFirst bool
|
|
// SkipHelpFlags tells the parser not to look for -h and --help flags and
|
|
// call the HelpHandler.
|
|
SkipHelpFlags bool
|
|
}
|
|
|
|
var PrintHelpAndExit = func(err error, usage string) {
|
|
if err != nil {
|
|
fmt.Fprintln(os.Stderr, usage)
|
|
os.Exit(1)
|
|
} else {
|
|
fmt.Println(usage)
|
|
os.Exit(0)
|
|
}
|
|
}
|
|
|
|
var PrintHelpOnly = func(err error, usage string) {
|
|
if err != nil {
|
|
fmt.Fprintln(os.Stderr, usage)
|
|
} else {
|
|
fmt.Println(usage)
|
|
}
|
|
}
|
|
|
|
var NoHelpHandler = func(err error, usage string) {}
|
|
|
|
var DefaultParser = &Parser{
|
|
HelpHandler: PrintHelpAndExit,
|
|
OptionsFirst: false,
|
|
SkipHelpFlags: false,
|
|
}
|
|
|
|
// ParseDoc parses os.Args[1:] based on the interface described in doc, using the default parser options.
|
|
func ParseDoc(doc string) (Opts, error) {
|
|
return ParseArgs(doc, nil, "")
|
|
}
|
|
|
|
// ParseArgs parses custom arguments based on the interface described in doc. If you provide a non-empty version
|
|
// string, then this will be displayed when the --version flag is found. This method uses the default parser options.
|
|
func ParseArgs(doc string, argv []string, version string) (Opts, error) {
|
|
return DefaultParser.ParseArgs(doc, argv, version)
|
|
}
|
|
|
|
// ParseArgs parses custom arguments based on the interface described in doc. If you provide a non-empty version
|
|
// string, then this will be displayed when the --version flag is found.
|
|
func (p *Parser) ParseArgs(doc string, argv []string, version string) (Opts, error) {
|
|
return p.parse(doc, argv, version)
|
|
}
|
|
|
|
// Deprecated: Parse is provided for backward compatibility with the original docopt.go package.
|
|
// Please rather make use of ParseDoc, ParseArgs, or use your own custom Parser.
|
|
func Parse(doc string, argv []string, help bool, version string, optionsFirst bool, exit ...bool) (map[string]interface{}, error) {
|
|
exitOk := true
|
|
if len(exit) > 0 {
|
|
exitOk = exit[0]
|
|
}
|
|
p := &Parser{
|
|
OptionsFirst: optionsFirst,
|
|
SkipHelpFlags: !help,
|
|
}
|
|
if exitOk {
|
|
p.HelpHandler = PrintHelpAndExit
|
|
} else {
|
|
p.HelpHandler = PrintHelpOnly
|
|
}
|
|
return p.parse(doc, argv, version)
|
|
}
|
|
|
|
func (p *Parser) parse(doc string, argv []string, version string) (map[string]interface{}, error) {
|
|
if argv == nil {
|
|
argv = os.Args[1:]
|
|
}
|
|
if p.HelpHandler == nil {
|
|
p.HelpHandler = DefaultParser.HelpHandler
|
|
}
|
|
args, output, err := parse(doc, argv, !p.SkipHelpFlags, version, p.OptionsFirst)
|
|
if _, ok := err.(*UserError); ok {
|
|
// the user gave us bad input
|
|
p.HelpHandler(err, output)
|
|
} else if len(output) > 0 && err == nil {
|
|
// the user asked for help or --version
|
|
p.HelpHandler(err, output)
|
|
}
|
|
return args, err
|
|
}
|
|
|
|
// -----------------------------------------------------------------------------
|
|
|
|
// parse and return a map of args, output and all errors
|
|
func parse(doc string, argv []string, help bool, version string, optionsFirst bool) (args map[string]interface{}, output string, err error) {
|
|
if argv == nil && len(os.Args) > 1 {
|
|
argv = os.Args[1:]
|
|
}
|
|
|
|
usageSections := parseSection("usage:", doc)
|
|
|
|
if len(usageSections) == 0 {
|
|
err = newLanguageError("\"usage:\" (case-insensitive) not found.")
|
|
return
|
|
}
|
|
if len(usageSections) > 1 {
|
|
err = newLanguageError("More than one \"usage:\" (case-insensitive).")
|
|
return
|
|
}
|
|
usage := usageSections[0]
|
|
|
|
options := parseDefaults(doc)
|
|
formal, err := formalUsage(usage)
|
|
if err != nil {
|
|
output = handleError(err, usage)
|
|
return
|
|
}
|
|
|
|
pat, err := parsePattern(formal, &options)
|
|
if err != nil {
|
|
output = handleError(err, usage)
|
|
return
|
|
}
|
|
|
|
patternArgv, err := parseArgv(newTokenList(argv, errorUser), &options, optionsFirst)
|
|
if err != nil {
|
|
output = handleError(err, usage)
|
|
return
|
|
}
|
|
patFlat, err := pat.flat(patternOption)
|
|
if err != nil {
|
|
output = handleError(err, usage)
|
|
return
|
|
}
|
|
patternOptions := patFlat.unique()
|
|
|
|
patFlat, err = pat.flat(patternOptionSSHORTCUT)
|
|
if err != nil {
|
|
output = handleError(err, usage)
|
|
return
|
|
}
|
|
for _, optionsShortcut := range patFlat {
|
|
docOptions := parseDefaults(doc)
|
|
optionsShortcut.children = docOptions.unique().diff(patternOptions)
|
|
}
|
|
|
|
if output = extras(help, version, patternArgv, doc); len(output) > 0 {
|
|
return
|
|
}
|
|
|
|
err = pat.fix()
|
|
if err != nil {
|
|
output = handleError(err, usage)
|
|
return
|
|
}
|
|
matched, left, collected := pat.match(&patternArgv, nil)
|
|
if matched && len(*left) == 0 {
|
|
patFlat, err = pat.flat(patternDefault)
|
|
if err != nil {
|
|
output = handleError(err, usage)
|
|
return
|
|
}
|
|
args = append(patFlat, *collected...).dictionary()
|
|
return
|
|
}
|
|
|
|
err = newUserError("")
|
|
output = handleError(err, usage)
|
|
return
|
|
}
|
|
|
|
func handleError(err error, usage string) string {
|
|
if _, ok := err.(*UserError); ok {
|
|
return strings.TrimSpace(fmt.Sprintf("%s\n%s", err, usage))
|
|
}
|
|
return ""
|
|
}
|
|
|
|
func parseSection(name, source string) []string {
|
|
p := regexp.MustCompile(`(?im)^([^\n]*` + name + `[^\n]*\n?(?:[ \t].*?(?:\n|$))*)`)
|
|
s := p.FindAllString(source, -1)
|
|
if s == nil {
|
|
s = []string{}
|
|
}
|
|
for i, v := range s {
|
|
s[i] = strings.TrimSpace(v)
|
|
}
|
|
return s
|
|
}
|
|
|
|
func parseDefaults(doc string) patternList {
|
|
defaults := patternList{}
|
|
p := regexp.MustCompile(`\n[ \t]*(-\S+?)`)
|
|
for _, s := range parseSection("options:", doc) {
|
|
// FIXME corner case "bla: options: --foo"
|
|
_, _, s = stringPartition(s, ":") // get rid of "options:"
|
|
split := p.Split("\n"+s, -1)[1:]
|
|
match := p.FindAllStringSubmatch("\n"+s, -1)
|
|
for i := range split {
|
|
optionDescription := match[i][1] + split[i]
|
|
if strings.HasPrefix(optionDescription, "-") {
|
|
defaults = append(defaults, parseOption(optionDescription))
|
|
}
|
|
}
|
|
}
|
|
return defaults
|
|
}
|
|
|
|
func parsePattern(source string, options *patternList) (*pattern, error) {
|
|
tokens := tokenListFromPattern(source)
|
|
result, err := parseExpr(tokens, options)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
if tokens.current() != nil {
|
|
return nil, tokens.errorFunc("unexpected ending: %s" + strings.Join(tokens.tokens, " "))
|
|
}
|
|
return newRequired(result...), nil
|
|
}
|
|
|
|
func parseArgv(tokens *tokenList, options *patternList, optionsFirst bool) (patternList, error) {
|
|
/*
|
|
Parse command-line argument vector.
|
|
|
|
If options_first:
|
|
argv ::= [ long | shorts ]* [ argument ]* [ '--' [ argument ]* ] ;
|
|
else:
|
|
argv ::= [ long | shorts | argument ]* [ '--' [ argument ]* ] ;
|
|
*/
|
|
parsed := patternList{}
|
|
for tokens.current() != nil {
|
|
if tokens.current().eq("--") {
|
|
for _, v := range tokens.tokens {
|
|
parsed = append(parsed, newArgument("", v))
|
|
}
|
|
return parsed, nil
|
|
} else if tokens.current().hasPrefix("--") {
|
|
pl, err := parseLong(tokens, options)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
parsed = append(parsed, pl...)
|
|
} else if tokens.current().hasPrefix("-") && !tokens.current().eq("-") {
|
|
ps, err := parseShorts(tokens, options)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
parsed = append(parsed, ps...)
|
|
} else if optionsFirst {
|
|
for _, v := range tokens.tokens {
|
|
parsed = append(parsed, newArgument("", v))
|
|
}
|
|
return parsed, nil
|
|
} else {
|
|
parsed = append(parsed, newArgument("", tokens.move().String()))
|
|
}
|
|
}
|
|
return parsed, nil
|
|
}
|
|
|
|
func parseOption(optionDescription string) *pattern {
|
|
optionDescription = strings.TrimSpace(optionDescription)
|
|
options, _, description := stringPartition(optionDescription, " ")
|
|
options = strings.Replace(options, ",", " ", -1)
|
|
options = strings.Replace(options, "=", " ", -1)
|
|
|
|
short := ""
|
|
long := ""
|
|
argcount := 0
|
|
var value interface{}
|
|
value = false
|
|
|
|
reDefault := regexp.MustCompile(`(?i)\[default: (.*)\]`)
|
|
for _, s := range strings.Fields(options) {
|
|
if strings.HasPrefix(s, "--") {
|
|
long = s
|
|
} else if strings.HasPrefix(s, "-") {
|
|
short = s
|
|
} else {
|
|
argcount = 1
|
|
}
|
|
if argcount > 0 {
|
|
matched := reDefault.FindAllStringSubmatch(description, -1)
|
|
if len(matched) > 0 {
|
|
value = matched[0][1]
|
|
} else {
|
|
value = nil
|
|
}
|
|
}
|
|
}
|
|
return newOption(short, long, argcount, value)
|
|
}
|
|
|
|
func parseExpr(tokens *tokenList, options *patternList) (patternList, error) {
|
|
// expr ::= seq ( '|' seq )* ;
|
|
seq, err := parseSeq(tokens, options)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
if !tokens.current().eq("|") {
|
|
return seq, nil
|
|
}
|
|
var result patternList
|
|
if len(seq) > 1 {
|
|
result = patternList{newRequired(seq...)}
|
|
} else {
|
|
result = seq
|
|
}
|
|
for tokens.current().eq("|") {
|
|
tokens.move()
|
|
seq, err = parseSeq(tokens, options)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
if len(seq) > 1 {
|
|
result = append(result, newRequired(seq...))
|
|
} else {
|
|
result = append(result, seq...)
|
|
}
|
|
}
|
|
if len(result) > 1 {
|
|
return patternList{newEither(result...)}, nil
|
|
}
|
|
return result, nil
|
|
}
|
|
|
|
func parseSeq(tokens *tokenList, options *patternList) (patternList, error) {
|
|
// seq ::= ( atom [ '...' ] )* ;
|
|
result := patternList{}
|
|
for !tokens.current().match(true, "]", ")", "|") {
|
|
atom, err := parseAtom(tokens, options)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
if tokens.current().eq("...") {
|
|
atom = patternList{newOneOrMore(atom...)}
|
|
tokens.move()
|
|
}
|
|
result = append(result, atom...)
|
|
}
|
|
return result, nil
|
|
}
|
|
|
|
func parseAtom(tokens *tokenList, options *patternList) (patternList, error) {
|
|
// atom ::= '(' expr ')' | '[' expr ']' | 'options' | long | shorts | argument | command ;
|
|
tok := tokens.current()
|
|
result := patternList{}
|
|
if tokens.current().match(false, "(", "[") {
|
|
tokens.move()
|
|
var matching string
|
|
pl, err := parseExpr(tokens, options)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
if tok.eq("(") {
|
|
matching = ")"
|
|
result = patternList{newRequired(pl...)}
|
|
} else if tok.eq("[") {
|
|
matching = "]"
|
|
result = patternList{newOptional(pl...)}
|
|
}
|
|
moved := tokens.move()
|
|
if !moved.eq(matching) {
|
|
return nil, tokens.errorFunc("unmatched '%s', expected: '%s' got: '%s'", tok, matching, moved)
|
|
}
|
|
return result, nil
|
|
} else if tok.eq("options") {
|
|
tokens.move()
|
|
return patternList{newOptionsShortcut()}, nil
|
|
} else if tok.hasPrefix("--") && !tok.eq("--") {
|
|
return parseLong(tokens, options)
|
|
} else if tok.hasPrefix("-") && !tok.eq("-") && !tok.eq("--") {
|
|
return parseShorts(tokens, options)
|
|
} else if tok.hasPrefix("<") && tok.hasSuffix(">") || tok.isUpper() {
|
|
return patternList{newArgument(tokens.move().String(), nil)}, nil
|
|
}
|
|
return patternList{newCommand(tokens.move().String(), false)}, nil
|
|
}
|
|
|
|
func parseLong(tokens *tokenList, options *patternList) (patternList, error) {
|
|
// long ::= '--' chars [ ( ' ' | '=' ) chars ] ;
|
|
long, eq, v := stringPartition(tokens.move().String(), "=")
|
|
var value interface{}
|
|
var opt *pattern
|
|
if eq == "" && v == "" {
|
|
value = nil
|
|
} else {
|
|
value = v
|
|
}
|
|
|
|
if !strings.HasPrefix(long, "--") {
|
|
return nil, newError("long option '%s' doesn't start with --", long)
|
|
}
|
|
similar := patternList{}
|
|
for _, o := range *options {
|
|
if o.long == long {
|
|
similar = append(similar, o)
|
|
}
|
|
}
|
|
if tokens.err == errorUser && len(similar) == 0 { // if no exact match
|
|
similar = patternList{}
|
|
for _, o := range *options {
|
|
if strings.HasPrefix(o.long, long) {
|
|
similar = append(similar, o)
|
|
}
|
|
}
|
|
}
|
|
if len(similar) > 1 { // might be simply specified ambiguously 2+ times?
|
|
similarLong := make([]string, len(similar))
|
|
for i, s := range similar {
|
|
similarLong[i] = s.long
|
|
}
|
|
return nil, tokens.errorFunc("%s is not a unique prefix: %s?", long, strings.Join(similarLong, ", "))
|
|
} else if len(similar) < 1 {
|
|
argcount := 0
|
|
if eq == "=" {
|
|
argcount = 1
|
|
}
|
|
opt = newOption("", long, argcount, false)
|
|
*options = append(*options, opt)
|
|
if tokens.err == errorUser {
|
|
var val interface{}
|
|
if argcount > 0 {
|
|
val = value
|
|
} else {
|
|
val = true
|
|
}
|
|
opt = newOption("", long, argcount, val)
|
|
}
|
|
} else {
|
|
opt = newOption(similar[0].short, similar[0].long, similar[0].argcount, similar[0].value)
|
|
if opt.argcount == 0 {
|
|
if value != nil {
|
|
return nil, tokens.errorFunc("%s must not have an argument", opt.long)
|
|
}
|
|
} else {
|
|
if value == nil {
|
|
if tokens.current().match(true, "--") {
|
|
return nil, tokens.errorFunc("%s requires argument", opt.long)
|
|
}
|
|
moved := tokens.move()
|
|
if moved != nil {
|
|
value = moved.String() // only set as string if not nil
|
|
}
|
|
}
|
|
}
|
|
if tokens.err == errorUser {
|
|
if value != nil {
|
|
opt.value = value
|
|
} else {
|
|
opt.value = true
|
|
}
|
|
}
|
|
}
|
|
|
|
return patternList{opt}, nil
|
|
}
|
|
|
|
func parseShorts(tokens *tokenList, options *patternList) (patternList, error) {
|
|
// shorts ::= '-' ( chars )* [ [ ' ' ] chars ] ;
|
|
tok := tokens.move()
|
|
if !tok.hasPrefix("-") || tok.hasPrefix("--") {
|
|
return nil, newError("short option '%s' doesn't start with -", tok)
|
|
}
|
|
left := strings.TrimLeft(tok.String(), "-")
|
|
parsed := patternList{}
|
|
for left != "" {
|
|
var opt *pattern
|
|
short := "-" + left[0:1]
|
|
left = left[1:]
|
|
similar := patternList{}
|
|
for _, o := range *options {
|
|
if o.short == short {
|
|
similar = append(similar, o)
|
|
}
|
|
}
|
|
if len(similar) > 1 {
|
|
return nil, tokens.errorFunc("%s is specified ambiguously %d times", short, len(similar))
|
|
} else if len(similar) < 1 {
|
|
opt = newOption(short, "", 0, false)
|
|
*options = append(*options, opt)
|
|
if tokens.err == errorUser {
|
|
opt = newOption(short, "", 0, true)
|
|
}
|
|
} else { // why copying is necessary here?
|
|
opt = newOption(short, similar[0].long, similar[0].argcount, similar[0].value)
|
|
var value interface{}
|
|
if opt.argcount > 0 {
|
|
if left == "" {
|
|
if tokens.current().match(true, "--") {
|
|
return nil, tokens.errorFunc("%s requires argument", short)
|
|
}
|
|
value = tokens.move().String()
|
|
} else {
|
|
value = left
|
|
left = ""
|
|
}
|
|
}
|
|
if tokens.err == errorUser {
|
|
if value != nil {
|
|
opt.value = value
|
|
} else {
|
|
opt.value = true
|
|
}
|
|
}
|
|
}
|
|
parsed = append(parsed, opt)
|
|
}
|
|
return parsed, nil
|
|
}
|
|
|
|
func formalUsage(section string) (string, error) {
|
|
_, _, section = stringPartition(section, ":") // drop "usage:"
|
|
pu := strings.Fields(section)
|
|
|
|
if len(pu) == 0 {
|
|
return "", newLanguageError("no fields found in usage (perhaps a spacing error).")
|
|
}
|
|
|
|
result := "( "
|
|
for _, s := range pu[1:] {
|
|
if s == pu[0] {
|
|
result += ") | ( "
|
|
} else {
|
|
result += s + " "
|
|
}
|
|
}
|
|
result += ")"
|
|
|
|
return result, nil
|
|
}
|
|
|
|
func extras(help bool, version string, options patternList, doc string) string {
|
|
if help {
|
|
for _, o := range options {
|
|
if (o.name == "-h" || o.name == "--help") && o.value == true {
|
|
return strings.Trim(doc, "\n")
|
|
}
|
|
}
|
|
}
|
|
if version != "" {
|
|
for _, o := range options {
|
|
if (o.name == "--version") && o.value == true {
|
|
return version
|
|
}
|
|
}
|
|
}
|
|
return ""
|
|
}
|
|
|
|
func stringPartition(s, sep string) (string, string, string) {
|
|
sepPos := strings.Index(s, sep)
|
|
if sepPos == -1 { // no seperator found
|
|
return s, "", ""
|
|
}
|
|
split := strings.SplitN(s, sep, 2)
|
|
return split[0], sep, split[1]
|
|
}
|