|
| 1 | +'use strict'; |
| 2 | + |
| 3 | +var arrayify = require('array-back'); |
| 4 | + |
| 5 | +/** |
| 6 | + * A module for testing for and extracting names from options (e.g. `--one`, `-o`) |
| 7 | + */ |
| 8 | + |
| 9 | +class Arg { |
| 10 | + constructor (re) { |
| 11 | + this.re = re; |
| 12 | + } |
| 13 | + |
| 14 | + test (arg) { |
| 15 | + return this.re.test(arg) |
| 16 | + } |
| 17 | +} |
| 18 | + |
| 19 | +const isShort = new Arg(/^-([^\d-])$/); |
| 20 | +const isLong = new Arg(/^--(\S+)/); |
| 21 | +const isCombined = new Arg(/^-([^\d-]{2,})$/); |
| 22 | +const isOption = function (arg) { |
| 23 | + return isShort.test(arg) || isLong.test(arg) || isCombined.test(arg) |
| 24 | +}; |
| 25 | + |
| 26 | +/** |
| 27 | + * @module command-line-commands |
| 28 | + * @example |
| 29 | + * const commandLineCommands = require('command-line-commands') |
| 30 | + */ |
| 31 | + |
| 32 | +/** |
| 33 | + * Parses the `argv` value supplied (or `process.argv` by default), extracting and returning the `command` and remainder of `argv`. The command will be the first value in the `argv` array unless it is an option (e.g. `--help`). |
| 34 | + * |
| 35 | + * @param {string|string[]} - One or more command strings, one of which the user must supply. Include `null` to represent "no command" (effectively making a command optional). |
| 36 | + * @param [argv] {string[]} - An argv array, defaults to the global `process.argv` if not supplied. |
| 37 | + * @returns {{ command: string, argv: string[] }} |
| 38 | + * @throws `INVALID_COMMAND` - user supplied a command not specified in `commands`. |
| 39 | + * @alias module:command-line-commands |
| 40 | + */ |
| 41 | +function commandLineCommands (commands, argv) { |
| 42 | + if (!commands || (Array.isArray(commands) && !commands.length)) { |
| 43 | + throw new Error('Please supply one or more commands') |
| 44 | + } |
| 45 | + if (argv) { |
| 46 | + argv = arrayify(argv); |
| 47 | + } else { |
| 48 | + /* if no argv supplied, assume we are parsing process.argv. */ |
| 49 | + /* never modify the global process.argv directly. */ |
| 50 | + argv = process.argv.slice(0); |
| 51 | + argv.splice(0, 2); |
| 52 | + } |
| 53 | + |
| 54 | + /* the command is the first arg, unless it's an option (e.g. --help) */ |
| 55 | + const command = (isOption(argv[0]) || !argv.length) ? null : argv.shift(); |
| 56 | + |
| 57 | + if (arrayify(commands).indexOf(command) === -1) { |
| 58 | + const err = new Error('Command not recognised: ' + command); |
| 59 | + err.command = command; |
| 60 | + err.name = 'INVALID_COMMAND'; |
| 61 | + throw err |
| 62 | + } |
| 63 | + |
| 64 | + return { command, argv } |
| 65 | +} |
| 66 | + |
| 67 | +module.exports = commandLineCommands; |
0 commit comments