12345678910111213141516171819202122232425262728293031323334353637383940414243444546474849505152535455565758596061626364656667686970717273 |
- const command = require('./command')()
- const YError = require('./yerror')
-
- const positionName = ['first', 'second', 'third', 'fourth', 'fifth', 'sixth']
-
- module.exports = function (expected, callerArguments, length) {
- // TODO: should this eventually raise an exception.
- try {
- // preface the argument description with "cmd", so
- // that we can run it through yargs' command parser.
- var position = 0
- var parsed = {demanded: [], optional: []}
- if (typeof expected === 'object') {
- length = callerArguments
- callerArguments = expected
- } else {
- parsed = command.parseCommand('cmd ' + expected)
- }
- const args = [].slice.call(callerArguments)
-
- while (args.length && args[args.length - 1] === undefined) args.pop()
- length = length || args.length
-
- if (length < parsed.demanded.length) {
- throw new YError('Not enough arguments provided. Expected ' + parsed.demanded.length +
- ' but received ' + args.length + '.')
- }
-
- const totalCommands = parsed.demanded.length + parsed.optional.length
- if (length > totalCommands) {
- throw new YError('Too many arguments provided. Expected max ' + totalCommands +
- ' but received ' + length + '.')
- }
-
- parsed.demanded.forEach(function (demanded) {
- const arg = args.shift()
- const observedType = guessType(arg)
- const matchingTypes = demanded.cmd.filter(function (type) {
- return type === observedType || type === '*'
- })
- if (matchingTypes.length === 0) argumentTypeError(observedType, demanded.cmd, position, false)
- position += 1
- })
-
- parsed.optional.forEach(function (optional) {
- if (args.length === 0) return
- const arg = args.shift()
- const observedType = guessType(arg)
- const matchingTypes = optional.cmd.filter(function (type) {
- return type === observedType || type === '*'
- })
- if (matchingTypes.length === 0) argumentTypeError(observedType, optional.cmd, position, true)
- position += 1
- })
- } catch (err) {
- console.warn(err.stack)
- }
- }
-
- function guessType (arg) {
- if (Array.isArray(arg)) {
- return 'array'
- } else if (arg === null) {
- return 'null'
- }
- return typeof arg
- }
-
- function argumentTypeError (observedType, allowedTypes, position, optional) {
- throw new YError('Invalid ' + (positionName[position] || 'manyith') + ' argument.' +
- ' Expected ' + allowedTypes.join(' or ') + ' but received ' + observedType + '.')
- }
|