shell-quote

Parse and quote shell commands.

example

quote

var quote = require('shell-quote/quote');
var s = quote([ 'a', 'b c d', '$f', '"g"' ]);
console.log(s);

output

a 'b c d' \$f '"g"'

parse

var parse = require('shell-quote/parse');
var xs = parse('a "b c" \\$def \'it\'\\\'\'s great\'');
console.dir(xs);

output

[ 'a', 'b c', '$def', "it's great" ]

parse with an environment variable

var parse = require('shell-quote/parse');
var xs = parse('beep --boop="$PWD"', { PWD: '/home/robot' });
console.dir(xs);

output

[ 'beep', '--boop=/home/robot' ]

parse with custom escape character

var parse = require('shell-quote/parse');
var xs = parse('beep ^--boop="$PWD"', { PWD: '/home/robot' }, { escape: '^' });
console.dir(xs);

output

[ 'beep', '--boop=/home/robot' ]

parse with unquoted variable splitting

var parse = require('shell-quote/parse');
var xs = parse('a $T', { T: 'c d' }, { splitUnquoted: true });
console.dir(xs);

output

[ 'a', 'c', 'd' ]

parsing shell operators

var parse = require('shell-quote/parse');
var xs = parse('beep || boop > /byte');
console.dir(xs);

output:

[ 'beep', { op: '||' }, 'boop', { op: '>' }, '/byte' ]

parsing shell comment

var parse = require('shell-quote/parse');
var xs = parse('beep > boop # > kaboom');
console.dir(xs);

output:

[ 'beep', { op: '>' }, 'boop', { comment: ' > kaboom' } ]

methods

var quote = require('shell-quote/quote');
var parse = require('shell-quote/parse');

quote(args)

Return a quoted string for the array args suitable for using in shell commands.

Each entry of args may be a string, or one of the object shapes that parse emits: { op } (where op is one of the control operators ||, &&, ;;, |&, <(, <<<, >>, >&, <&, &, ;, (, ), |, <, >), { op: 'glob', pattern }, or { comment }. Any other object shape, an unrecognized op, or a pattern/comment containing line terminators throws a TypeError.

The output is POSIX shell (sh/bash) quoting. It is not valid for Windows cmd.exe or PowerShell, whose rules differ and, for cmd.exe, are not solvable in the general case. On Windows, do not build a shell command string from this output; instead pass an argument array to a non-shell API such as child_process.execFile or spawn (or the cross-spawn package), which does no shell parsing and needs no quoting.

Use the returned string verbatim as shell input. It is already a complete, escaped shell word (or words); do not wrap it in additional quotes or embed it in eval '...'. Re-quoting the output (for example, placing it inside single quotes) turns its backslash escapes into literal characters and corrupts the value.

parse(cmd, env={})

Return an array of arguments from the quoted string cmd.

Interpolate embedded bash-style $VARNAME and ${VARNAME} variables with the env object which like bash will replace undefined variables with "".

By default an expanded variable is a single token even when unquoted. Pass { splitUnquoted: true } to split an unquoted expansion into multiple tokens the way a shell performs field splitting, using the default IFS (space, tab, newline). Pass a string to use its characters as the IFS instead (for example { splitUnquoted: ':' }). A quoted expansion ("$VAR") is never split.

Only simple $VARNAME and ${VARNAME} interpolation is supported. Bash parameter expansion beyond a plain variable name is not evaluated: forms such as array subscripts (${arr[i]}), length (${#arr[@]}), and modifiers (${var:-default}, ${var/a/b}) are treated as an unknown variable and expand to "", while arithmetic ($((...))) and command substitution ($(...)) are not interpreted. Whitespace inside ${...} throws a Bad substitution error.

env is usually an object but it can also be a function to perform lookups. When env(key) returns a string, its result will be output just like env[key] would. When env(key) returns an object, it will be inserted into the result array like the operator objects.

When a bash operator is encountered, the element in the array with be an object with an "op" key set to the operator string. For example:

'beep || boop > /byte'

parses as:

[ 'beep', { op: '||' }, 'boop', { op: '>' }, '/byte' ]

install

With npm do:

npm install shell-quote

license

MIT