123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195 |
- const flagSymbol = Symbol('arg flag');
- class ArgError extends Error {
- constructor(msg, code) {
- super(msg);
- this.name = 'ArgError';
- this.code = code;
- Object.setPrototypeOf(this, ArgError.prototype);
- }
- }
- function arg(
- opts,
- {
- argv = process.argv.slice(2),
- permissive = false,
- stopAtPositional = false
- } = {}
- ) {
- if (!opts) {
- throw new ArgError(
- 'argument specification object is required',
- 'ARG_CONFIG_NO_SPEC'
- );
- }
- const result = { _: [] };
- const aliases = {};
- const handlers = {};
- for (const key of Object.keys(opts)) {
- if (!key) {
- throw new ArgError(
- 'argument key cannot be an empty string',
- 'ARG_CONFIG_EMPTY_KEY'
- );
- }
- if (key[0] !== '-') {
- throw new ArgError(
- `argument key must start with '-' but found: '${key}'`,
- 'ARG_CONFIG_NONOPT_KEY'
- );
- }
- if (key.length === 1) {
- throw new ArgError(
- `argument key must have a name; singular '-' keys are not allowed: ${key}`,
- 'ARG_CONFIG_NONAME_KEY'
- );
- }
- if (typeof opts[key] === 'string') {
- aliases[key] = opts[key];
- continue;
- }
- let type = opts[key];
- let isFlag = false;
- if (
- Array.isArray(type) &&
- type.length === 1 &&
- typeof type[0] === 'function'
- ) {
- const [fn] = type;
- type = (value, name, prev = []) => {
- prev.push(fn(value, name, prev[prev.length - 1]));
- return prev;
- };
- isFlag = fn === Boolean || fn[flagSymbol] === true;
- } else if (typeof type === 'function') {
- isFlag = type === Boolean || type[flagSymbol] === true;
- } else {
- throw new ArgError(
- `type missing or not a function or valid array type: ${key}`,
- 'ARG_CONFIG_VAD_TYPE'
- );
- }
- if (key[1] !== '-' && key.length > 2) {
- throw new ArgError(
- `short argument keys (with a single hyphen) must have only one character: ${key}`,
- 'ARG_CONFIG_SHORTOPT_TOOLONG'
- );
- }
- handlers[key] = [type, isFlag];
- }
- for (let i = 0, len = argv.length; i < len; i++) {
- const wholeArg = argv[i];
- if (stopAtPositional && result._.length > 0) {
- result._ = result._.concat(argv.slice(i));
- break;
- }
- if (wholeArg === '--') {
- result._ = result._.concat(argv.slice(i + 1));
- break;
- }
- if (wholeArg.length > 1 && wholeArg[0] === '-') {
- /* eslint-disable operator-linebreak */
- const separatedArguments =
- wholeArg[1] === '-' || wholeArg.length === 2
- ? [wholeArg]
- : wholeArg
- .slice(1)
- .split('')
- .map((a) => `-${a}`);
- /* eslint-enable operator-linebreak */
- for (let j = 0; j < separatedArguments.length; j++) {
- const arg = separatedArguments[j];
- const [originalArgName, argStr] =
- arg[1] === '-' ? arg.split(/=(.*)/, 2) : [arg, undefined];
- let argName = originalArgName;
- while (argName in aliases) {
- argName = aliases[argName];
- }
- if (!(argName in handlers)) {
- if (permissive) {
- result._.push(arg);
- continue;
- } else {
- throw new ArgError(
- `unknown or unexpected option: ${originalArgName}`,
- 'ARG_UNKNOWN_OPTION'
- );
- }
- }
- const [type, isFlag] = handlers[argName];
- if (!isFlag && j + 1 < separatedArguments.length) {
- throw new ArgError(
- `option requires argument (but was followed by another short argument): ${originalArgName}`,
- 'ARG_MISSING_REQUIRED_SHORTARG'
- );
- }
- if (isFlag) {
- result[argName] = type(true, argName, result[argName]);
- } else if (argStr === undefined) {
- if (
- argv.length < i + 2 ||
- (argv[i + 1].length > 1 &&
- argv[i + 1][0] === '-' &&
- !(
- argv[i + 1].match(/^-?\d*(\.(?=\d))?\d*$/) &&
- (type === Number ||
- // eslint-disable-next-line no-undef
- (typeof BigInt !== 'undefined' && type === BigInt))
- ))
- ) {
- const extended =
- originalArgName === argName ? '' : ` (alias for ${argName})`;
- throw new ArgError(
- `option requires argument: ${originalArgName}${extended}`,
- 'ARG_MISSING_REQUIRED_LONGARG'
- );
- }
- result[argName] = type(argv[i + 1], argName, result[argName]);
- ++i;
- } else {
- result[argName] = type(argStr, argName, result[argName]);
- }
- }
- } else {
- result._.push(wholeArg);
- }
- }
- return result;
- }
- arg.flag = (fn) => {
- fn[flagSymbol] = true;
- return fn;
- };
- // Utility types
- arg.COUNT = arg.flag((v, name, existingCount) => (existingCount || 0) + 1);
- // Expose error class
- arg.ArgError = ArgError;
- module.exports = arg;
|