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Diffstat (limited to '')
-rw-r--r-- | dependencies/pkg/mod/github.com/jessevdk/go-flags@v1.5.0/parser.go | 714 |
1 files changed, 714 insertions, 0 deletions
diff --git a/dependencies/pkg/mod/github.com/jessevdk/go-flags@v1.5.0/parser.go b/dependencies/pkg/mod/github.com/jessevdk/go-flags@v1.5.0/parser.go new file mode 100644 index 0000000..3fc3f7b --- /dev/null +++ b/dependencies/pkg/mod/github.com/jessevdk/go-flags@v1.5.0/parser.go @@ -0,0 +1,714 @@ +// Copyright 2012 Jesse van den Kieboom. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package flags + +import ( + "bytes" + "fmt" + "os" + "path" + "reflect" + "sort" + "strings" + "unicode/utf8" +) + +// A Parser provides command line option parsing. It can contain several +// option groups each with their own set of options. +type Parser struct { + // Embedded, see Command for more information + *Command + + // A usage string to be displayed in the help message. + Usage string + + // Option flags changing the behavior of the parser. + Options Options + + // NamespaceDelimiter separates group namespaces and option long names + NamespaceDelimiter string + + // EnvNamespaceDelimiter separates group env namespaces and env keys + EnvNamespaceDelimiter string + + // UnknownOptionsHandler is a function which gets called when the parser + // encounters an unknown option. The function receives the unknown option + // name, a SplitArgument which specifies its value if set with an argument + // separator, and the remaining command line arguments. + // It should return a new list of remaining arguments to continue parsing, + // or an error to indicate a parse failure. + UnknownOptionHandler func(option string, arg SplitArgument, args []string) ([]string, error) + + // CompletionHandler is a function gets called to handle the completion of + // items. By default, the items are printed and the application is exited. + // You can override this default behavior by specifying a custom CompletionHandler. + CompletionHandler func(items []Completion) + + // CommandHandler is a function that gets called to handle execution of a + // command. By default, the command will simply be executed. This can be + // overridden to perform certain actions (such as applying global flags) + // just before the command is executed. Note that if you override the + // handler it is your responsibility to call the command.Execute function. + // + // The command passed into CommandHandler may be nil in case there is no + // command to be executed when parsing has finished. + CommandHandler func(command Commander, args []string) error + + internalError error +} + +// SplitArgument represents the argument value of an option that was passed using +// an argument separator. +type SplitArgument interface { + // String returns the option's value as a string, and a boolean indicating + // if the option was present. + Value() (string, bool) +} + +type strArgument struct { + value *string +} + +func (s strArgument) Value() (string, bool) { + if s.value == nil { + return "", false + } + + return *s.value, true +} + +// Options provides parser options that change the behavior of the option +// parser. +type Options uint + +const ( + // None indicates no options. + None Options = 0 + + // HelpFlag adds a default Help Options group to the parser containing + // -h and --help options. When either -h or --help is specified on the + // command line, the parser will return the special error of type + // ErrHelp. When PrintErrors is also specified, then the help message + // will also be automatically printed to os.Stdout. + HelpFlag = 1 << iota + + // PassDoubleDash passes all arguments after a double dash, --, as + // remaining command line arguments (i.e. they will not be parsed for + // flags). + PassDoubleDash + + // IgnoreUnknown ignores any unknown options and passes them as + // remaining command line arguments instead of generating an error. + IgnoreUnknown + + // PrintErrors prints any errors which occurred during parsing to + // os.Stderr. In the special case of ErrHelp, the message will be printed + // to os.Stdout. + PrintErrors + + // PassAfterNonOption passes all arguments after the first non option + // as remaining command line arguments. This is equivalent to strict + // POSIX processing. + PassAfterNonOption + + // Default is a convenient default set of options which should cover + // most of the uses of the flags package. + Default = HelpFlag | PrintErrors | PassDoubleDash +) + +type parseState struct { + arg string + args []string + retargs []string + positional []*Arg + err error + + command *Command + lookup lookup +} + +// Parse is a convenience function to parse command line options with default +// settings. The provided data is a pointer to a struct representing the +// default option group (named "Application Options"). For more control, use +// flags.NewParser. +func Parse(data interface{}) ([]string, error) { + return NewParser(data, Default).Parse() +} + +// ParseArgs is a convenience function to parse command line options with default +// settings. The provided data is a pointer to a struct representing the +// default option group (named "Application Options"). The args argument is +// the list of command line arguments to parse. If you just want to parse the +// default program command line arguments (i.e. os.Args), then use flags.Parse +// instead. For more control, use flags.NewParser. +func ParseArgs(data interface{}, args []string) ([]string, error) { + return NewParser(data, Default).ParseArgs(args) +} + +// NewParser creates a new parser. It uses os.Args[0] as the application +// name and then calls Parser.NewNamedParser (see Parser.NewNamedParser for +// more details). The provided data is a pointer to a struct representing the +// default option group (named "Application Options"), or nil if the default +// group should not be added. The options parameter specifies a set of options +// for the parser. +func NewParser(data interface{}, options Options) *Parser { + p := NewNamedParser(path.Base(os.Args[0]), options) + + if data != nil { + g, err := p.AddGroup("Application Options", "", data) + + if err == nil { + g.parent = p + } + + p.internalError = err + } + + return p +} + +// NewNamedParser creates a new parser. The appname is used to display the +// executable name in the built-in help message. Option groups and commands can +// be added to this parser by using AddGroup and AddCommand. +func NewNamedParser(appname string, options Options) *Parser { + p := &Parser{ + Command: newCommand(appname, "", "", nil), + Options: options, + NamespaceDelimiter: ".", + EnvNamespaceDelimiter: "_", + } + + p.Command.parent = p + + return p +} + +// Parse parses the command line arguments from os.Args using Parser.ParseArgs. +// For more detailed information see ParseArgs. +func (p *Parser) Parse() ([]string, error) { + return p.ParseArgs(os.Args[1:]) +} + +// ParseArgs parses the command line arguments according to the option groups that +// were added to the parser. On successful parsing of the arguments, the +// remaining, non-option, arguments (if any) are returned. The returned error +// indicates a parsing error and can be used with PrintError to display +// contextual information on where the error occurred exactly. +// +// When the common help group has been added (AddHelp) and either -h or --help +// was specified in the command line arguments, a help message will be +// automatically printed if the PrintErrors option is enabled. +// Furthermore, the special error type ErrHelp is returned. +// It is up to the caller to exit the program if so desired. +func (p *Parser) ParseArgs(args []string) ([]string, error) { + if p.internalError != nil { + return nil, p.internalError + } + + p.eachOption(func(c *Command, g *Group, option *Option) { + option.clearReferenceBeforeSet = true + option.updateDefaultLiteral() + }) + + // Add built-in help group to all commands if necessary + if (p.Options & HelpFlag) != None { + p.addHelpGroups(p.showBuiltinHelp) + } + + compval := os.Getenv("GO_FLAGS_COMPLETION") + + if len(compval) != 0 { + comp := &completion{parser: p} + items := comp.complete(args) + + if p.CompletionHandler != nil { + p.CompletionHandler(items) + } else { + comp.print(items, compval == "verbose") + os.Exit(0) + } + + return nil, nil + } + + s := &parseState{ + args: args, + retargs: make([]string, 0, len(args)), + } + + p.fillParseState(s) + + for !s.eof() { + var err error + arg := s.pop() + + // When PassDoubleDash is set and we encounter a --, then + // simply append all the rest as arguments and break out + if (p.Options&PassDoubleDash) != None && arg == "--" { + s.addArgs(s.args...) + break + } + + if !argumentIsOption(arg) { + if (p.Options&PassAfterNonOption) != None && s.lookup.commands[arg] == nil { + // If PassAfterNonOption is set then all remaining arguments + // are considered positional + if err = s.addArgs(s.arg); err != nil { + break + } + + if err = s.addArgs(s.args...); err != nil { + break + } + + break + } + + // Note: this also sets s.err, so we can just check for + // nil here and use s.err later + if p.parseNonOption(s) != nil { + break + } + + continue + } + + prefix, optname, islong := stripOptionPrefix(arg) + optname, _, argument := splitOption(prefix, optname, islong) + + if islong { + err = p.parseLong(s, optname, argument) + } else { + err = p.parseShort(s, optname, argument) + } + + if err != nil { + ignoreUnknown := (p.Options & IgnoreUnknown) != None + parseErr := wrapError(err) + + if parseErr.Type != ErrUnknownFlag || (!ignoreUnknown && p.UnknownOptionHandler == nil) { + s.err = parseErr + break + } + + if ignoreUnknown { + s.addArgs(arg) + } else if p.UnknownOptionHandler != nil { + modifiedArgs, err := p.UnknownOptionHandler(optname, strArgument{argument}, s.args) + + if err != nil { + s.err = err + break + } + + s.args = modifiedArgs + } + } + } + + if s.err == nil { + p.eachOption(func(c *Command, g *Group, option *Option) { + err := option.clearDefault() + if err != nil { + if _, ok := err.(*Error); !ok { + err = p.marshalError(option, err) + } + s.err = err + } + }) + + s.checkRequired(p) + } + + var reterr error + + if s.err != nil { + reterr = s.err + } else if len(s.command.commands) != 0 && !s.command.SubcommandsOptional { + reterr = s.estimateCommand() + } else if cmd, ok := s.command.data.(Commander); ok { + if p.CommandHandler != nil { + reterr = p.CommandHandler(cmd, s.retargs) + } else { + reterr = cmd.Execute(s.retargs) + } + } else if p.CommandHandler != nil { + reterr = p.CommandHandler(nil, s.retargs) + } + + if reterr != nil { + var retargs []string + + if ourErr, ok := reterr.(*Error); !ok || ourErr.Type != ErrHelp { + retargs = append([]string{s.arg}, s.args...) + } else { + retargs = s.args + } + + return retargs, p.printError(reterr) + } + + return s.retargs, nil +} + +func (p *parseState) eof() bool { + return len(p.args) == 0 +} + +func (p *parseState) pop() string { + if p.eof() { + return "" + } + + p.arg = p.args[0] + p.args = p.args[1:] + + return p.arg +} + +func (p *parseState) peek() string { + if p.eof() { + return "" + } + + return p.args[0] +} + +func (p *parseState) checkRequired(parser *Parser) error { + c := parser.Command + + var required []*Option + + for c != nil { + c.eachGroup(func(g *Group) { + for _, option := range g.options { + if !option.isSet && option.Required { + required = append(required, option) + } + } + }) + + c = c.Active + } + + if len(required) == 0 { + if len(p.positional) > 0 { + var reqnames []string + + for _, arg := range p.positional { + argRequired := (!arg.isRemaining() && p.command.ArgsRequired) || arg.Required != -1 || arg.RequiredMaximum != -1 + + if !argRequired { + continue + } + + if arg.isRemaining() { + if arg.value.Len() < arg.Required { + var arguments string + + if arg.Required > 1 { + arguments = "arguments, but got only " + fmt.Sprintf("%d", arg.value.Len()) + } else { + arguments = "argument" + } + + reqnames = append(reqnames, "`"+arg.Name+" (at least "+fmt.Sprintf("%d", arg.Required)+" "+arguments+")`") + } else if arg.RequiredMaximum != -1 && arg.value.Len() > arg.RequiredMaximum { + if arg.RequiredMaximum == 0 { + reqnames = append(reqnames, "`"+arg.Name+" (zero arguments)`") + } else { + var arguments string + + if arg.RequiredMaximum > 1 { + arguments = "arguments, but got " + fmt.Sprintf("%d", arg.value.Len()) + } else { + arguments = "argument" + } + + reqnames = append(reqnames, "`"+arg.Name+" (at most "+fmt.Sprintf("%d", arg.RequiredMaximum)+" "+arguments+")`") + } + } + } else { + reqnames = append(reqnames, "`"+arg.Name+"`") + } + } + + if len(reqnames) == 0 { + return nil + } + + var msg string + + if len(reqnames) == 1 { + msg = fmt.Sprintf("the required argument %s was not provided", reqnames[0]) + } else { + msg = fmt.Sprintf("the required arguments %s and %s were not provided", + strings.Join(reqnames[:len(reqnames)-1], ", "), reqnames[len(reqnames)-1]) + } + + p.err = newError(ErrRequired, msg) + return p.err + } + + return nil + } + + names := make([]string, 0, len(required)) + + for _, k := range required { + names = append(names, "`"+k.String()+"'") + } + + sort.Strings(names) + + var msg string + + if len(names) == 1 { + msg = fmt.Sprintf("the required flag %s was not specified", names[0]) + } else { + msg = fmt.Sprintf("the required flags %s and %s were not specified", + strings.Join(names[:len(names)-1], ", "), names[len(names)-1]) + } + + p.err = newError(ErrRequired, msg) + return p.err +} + +func (p *parseState) estimateCommand() error { + commands := p.command.sortedVisibleCommands() + cmdnames := make([]string, len(commands)) + + for i, v := range commands { + cmdnames[i] = v.Name + } + + var msg string + var errtype ErrorType + + if len(p.retargs) != 0 { + c, l := closestChoice(p.retargs[0], cmdnames) + msg = fmt.Sprintf("Unknown command `%s'", p.retargs[0]) + errtype = ErrUnknownCommand + + if float32(l)/float32(len(c)) < 0.5 { + msg = fmt.Sprintf("%s, did you mean `%s'?", msg, c) + } else if len(cmdnames) == 1 { + msg = fmt.Sprintf("%s. You should use the %s command", + msg, + cmdnames[0]) + } else if len(cmdnames) > 1 { + msg = fmt.Sprintf("%s. Please specify one command of: %s or %s", + msg, + strings.Join(cmdnames[:len(cmdnames)-1], ", "), + cmdnames[len(cmdnames)-1]) + } + } else { + errtype = ErrCommandRequired + + if len(cmdnames) == 1 { + msg = fmt.Sprintf("Please specify the %s command", cmdnames[0]) + } else if len(cmdnames) > 1 { + msg = fmt.Sprintf("Please specify one command of: %s or %s", + strings.Join(cmdnames[:len(cmdnames)-1], ", "), + cmdnames[len(cmdnames)-1]) + } + } + + return newError(errtype, msg) +} + +func (p *Parser) parseOption(s *parseState, name string, option *Option, canarg bool, argument *string) (err error) { + if !option.canArgument() { + if argument != nil { + return newErrorf(ErrNoArgumentForBool, "bool flag `%s' cannot have an argument", option) + } + + err = option.set(nil) + } else if argument != nil || (canarg && !s.eof()) { + var arg string + + if argument != nil { + arg = *argument + } else { + arg = s.pop() + + if validationErr := option.isValidValue(arg); validationErr != nil { + return newErrorf(ErrExpectedArgument, validationErr.Error()) + } else if p.Options&PassDoubleDash != 0 && arg == "--" { + return newErrorf(ErrExpectedArgument, "expected argument for flag `%s', but got double dash `--'", option) + } + } + + if option.tag.Get("unquote") != "false" { + arg, err = unquoteIfPossible(arg) + } + + if err == nil { + err = option.set(&arg) + } + } else if option.OptionalArgument { + option.empty() + + for _, v := range option.OptionalValue { + err = option.set(&v) + + if err != nil { + break + } + } + } else { + err = newErrorf(ErrExpectedArgument, "expected argument for flag `%s'", option) + } + + if err != nil { + if _, ok := err.(*Error); !ok { + err = p.marshalError(option, err) + } + } + + return err +} + +func (p *Parser) marshalError(option *Option, err error) *Error { + s := "invalid argument for flag `%s'" + + expected := p.expectedType(option) + + if expected != "" { + s = s + " (expected " + expected + ")" + } + + return newErrorf(ErrMarshal, s+": %s", + option, + err.Error()) +} + +func (p *Parser) expectedType(option *Option) string { + valueType := option.value.Type() + + if valueType.Kind() == reflect.Func { + return "" + } + + return valueType.String() +} + +func (p *Parser) parseLong(s *parseState, name string, argument *string) error { + if option := s.lookup.longNames[name]; option != nil { + // Only long options that are required can consume an argument + // from the argument list + canarg := !option.OptionalArgument + + return p.parseOption(s, name, option, canarg, argument) + } + + return newErrorf(ErrUnknownFlag, "unknown flag `%s'", name) +} + +func (p *Parser) splitShortConcatArg(s *parseState, optname string) (string, *string) { + c, n := utf8.DecodeRuneInString(optname) + + if n == len(optname) { + return optname, nil + } + + first := string(c) + + if option := s.lookup.shortNames[first]; option != nil && option.canArgument() { + arg := optname[n:] + return first, &arg + } + + return optname, nil +} + +func (p *Parser) parseShort(s *parseState, optname string, argument *string) error { + if argument == nil { + optname, argument = p.splitShortConcatArg(s, optname) + } + + for i, c := range optname { + shortname := string(c) + + if option := s.lookup.shortNames[shortname]; option != nil { + // Only the last short argument can consume an argument from + // the arguments list, and only if it's non optional + canarg := (i+utf8.RuneLen(c) == len(optname)) && !option.OptionalArgument + + if err := p.parseOption(s, shortname, option, canarg, argument); err != nil { + return err + } + } else { + return newErrorf(ErrUnknownFlag, "unknown flag `%s'", shortname) + } + + // Only the first option can have a concatted argument, so just + // clear argument here + argument = nil + } + + return nil +} + +func (p *parseState) addArgs(args ...string) error { + for len(p.positional) > 0 && len(args) > 0 { + arg := p.positional[0] + + if err := convert(args[0], arg.value, arg.tag); err != nil { + p.err = err + return err + } + + if !arg.isRemaining() { + p.positional = p.positional[1:] + } + + args = args[1:] + } + + p.retargs = append(p.retargs, args...) + return nil +} + +func (p *Parser) parseNonOption(s *parseState) error { + if len(s.positional) > 0 { + return s.addArgs(s.arg) + } + + if len(s.command.commands) > 0 && len(s.retargs) == 0 { + if cmd := s.lookup.commands[s.arg]; cmd != nil { + s.command.Active = cmd + cmd.fillParseState(s) + + return nil + } else if !s.command.SubcommandsOptional { + s.addArgs(s.arg) + return newErrorf(ErrUnknownCommand, "Unknown command `%s'", s.arg) + } + } + + return s.addArgs(s.arg) +} + +func (p *Parser) showBuiltinHelp() error { + var b bytes.Buffer + + p.WriteHelp(&b) + return newError(ErrHelp, b.String()) +} + +func (p *Parser) printError(err error) error { + if err != nil && (p.Options&PrintErrors) != None { + flagsErr, ok := err.(*Error) + + if ok && flagsErr.Type == ErrHelp { + fmt.Fprintln(os.Stdout, err) + } else { + fmt.Fprintln(os.Stderr, err) + } + } + + return err +} |