node-query/node_modules/getargs/index.js

101 lines
2.4 KiB
JavaScript

var is = {
'string': function(s){ return typeof s === 'string' },
'function': function(f){ return typeof f === 'function' },
'number': function(f){ return typeof f === 'number' },
'array': Array.isArray || function(a){ return a instanceof Array },
'object': function(o){ return typeof o === 'object' && o != null },
'boolean': function(b){ return typeof b === 'boolean' }
}
function ArgSpec(str){
var ret
str = str.trim()
var parts = str.split(':')
if (parts.length > 1){
ret = {
name: parts[0],
type: parts[1].split('|')
}
}else if (parts.length === 1){
ret = {
name: str
}
}else{
throw new Error('Expected arg spec to be format name or name:type but was ' + str)
}
var m
if (m = ret.name.match(/^\[(.+)\]$/)){
ret.name = m[1]
ret.optional = true
}
if (m = ret.name.match(/^\.\.\.(.+)$/)){
ret.name = m[1]
ret.spread = true
}
return ret
}
function typeMatches(spec, arg) {
if (!spec.type) return true
var match = false;
var type = null;
for (var i = 0; i<spec.type.length; i++ ) {
type = spec.type[i];
var fun = is[type.toLowerCase()]
if (!fun) {
throw new Error('Unknown type: ' + spec.type)
}
match = fun(arg);
if (match) break;
}
return match;
}
module.exports = function getArgs(spec, args, target){
var ret = target || {}
spec = spec.split(',').map(function(s){
s = ArgSpec(s);
return s;
})
var minExpected = spec.filter(function(s){
return !s.optional
}).length
var maxExpected = spec.length
var argIdxOffset = 0
var length = Math.max(spec.length, args.length)
for (var i = 0; i < length; i++){
var sp = spec[i]
var argIdx = i + argIdxOffset
if (argIdx >= args.length){
if (argIdx < minExpected){
throw new Error(
'Not enough arguments, expected ' +
minExpected + ', got ' + argIdx)
}
break
}
if (argIdx >= maxExpected){
throw new Error('Too many arguments, expected ' +
maxExpected + ', got ' + (argIdx + 1))
}
var arg = args[argIdx]
if (typeMatches(sp, arg)){
if (sp.spread){
ret[sp.name] = Array.prototype.slice.call(args, argIdx)
break
}else{
ret[sp.name] = arg
}
}else if (sp.optional){
argIdxOffset--
}else{
throw new Error('Expected ' + sp.name +
'(pos ' + i + ') to be a ' + sp.type.join(' or '))
}
}
return ret
}