argv

README

Argv

Argv is a library for Go to split command line string into arguments array.

Documentation

Documentation can be found at Godoc

Example

func TestArgv(t *testing.T) {
	args, err := argv.Argv([]rune(" ls   `echo /`   |  wc  -l "), argv.ParseEnv(os.Environ()), argv.Run)
	if err != nil {
	    t.Fatal(err)
	}
	expects := [][]string{
	    []string{"ls", "/"},
	    []string{"wc", "-l"},
	}
	if !reflect.DeepEqual(args, expects) {
	    t.Fatal(args)
	}
}

LICENSE

MIT.

Documentation

Overview

Package argv parse command line string into arguments array using the bash syntax.

Index

• Variables
• func Argv(cmdline string, backquoteExpander, stringExpander Expander) ([][]string, error)
• func Cmds(args ...[]string) ([]*exec.Cmd, error)
• func Pipe(stdin io.Reader, stdout, stderr io.Writer, cmds ...*exec.Cmd) error
• type Expander
• type Parser
  • func NewParser(s *Scanner, backQuoteExpander, stringExpander Expander) *Parser
  • func (p *Parser) Parse() ([][]string, error)
• type Scanner
  • func NewScanner(text string) *Scanner
  • func (s *Scanner) Next() (Token, error)
• type Token
  • func Scan(text string) ([]Token, error)
• type TokenType

Variables

var (
	// ErrInvalidSyntax was reported if there is a syntax error in command line string.
	ErrInvalidSyntax = errors.New("invalid syntax")
)

Functions

func Argv

func Argv(cmdline string, backquoteExpander, stringExpander Expander) ([][]string, error)

Argv split cmdline string as array of argument array by the '|' character.

The parsing rules is same as bash. The environment variable will be replaced and string surround by '`' will be passed to reverse quote parser.

func Cmds

func Cmds(args ...[]string) ([]*exec.Cmd, error)

func Pipe

func Pipe(stdin io.Reader, stdout, stderr io.Writer, cmds ...*exec.Cmd) error

Types

type Expander

type Expander func(string) (string, error)

type Parser

type Parser struct {
	// contains filtered or unexported fields
}

Parser take tokens from Scanner, and do syntax checking, and generate the splitted arguments array.

func NewParser

func NewParser(s *Scanner, backQuoteExpander, stringExpander Expander) *Parser

NewParser create a cmdline string parser.

func (*Parser) Parse

func (p *Parser) Parse() ([][]string, error)

Parse split command line string into arguments array.

EBNF:

Cmdline = Section [ Pipe Cmdline ]
Section = [Space] SpacedSection { SpacedSection }
SpacedSection = MultipleUnit [Space]
MultipleUnit = Unit {Unit}
Unit = String | BackQuote | SingleQuote | DoubleQuote

type Scanner

type Scanner struct {
	// contains filtered or unexported fields
}

Scanner is a cmdline string scanner.

It split cmdline string to tokens: space, string, pipe, reverse quote string.

func NewScanner

func NewScanner(text string) *Scanner

NewScanner create a scanner and init it's internal states.

func (*Scanner) Next

func (s *Scanner) Next() (Token, error)

Next return next token, if it reach the end, TOK_EOF will be returned.

Error is returned for invalid syntax such as unpaired quotes.

type Token

type Token struct {
	Type  TokenType
	Value []rune
}

Token is generated by the scanner with a type and value.

func Scan

func Scan(text string) ([]Token, error)

Scan is a utility function help split input text as tokens.

type TokenType

type TokenType uint32

TokenType is the type of tokens recognized by the scanner.

const (
	// TokString for string
	TokString TokenType = iota + 1
	TokStringSingleQuote
	TokStringDoubleQuote
	// TokPipe is the '|' character
	TokPipe
	// TokBackQuote is reverse quoted string
	TokBackQuote
	// TokSpace represent space character sequence
	TokSpace
	// TokEOF means the input end.
	TokEOF
)