var util = require('util'); var tokenize = function(/*String*/ str, /*RegExp*/ re, /*Function?*/ parseDelim, /*Object?*/ instance){ // summary: // Split a string by a regular expression with the ability to capture the delimeters // parseDelim: // Each group (excluding the 0 group) is passed as a parameter. If the function returns // a value, it's added to the list of tokens. // instance: // Used as the "this' instance when calling parseDelim var tokens = []; var match, content, lastIndex = 0; while((match = re.exec(str))){ content = str.slice(lastIndex, re.lastIndex - match[0].length); if(content.length){ tokens.push(content); } if(parseDelim){ var parsed = parseDelim.apply(instance, match.slice(1).concat(tokens.length)); if(typeof parsed != 'undefined'){ if(parsed.specifier === '%'){ tokens.push('%'); }else{ tokens.push(parsed); } } } lastIndex = re.lastIndex; } content = str.slice(lastIndex); if(content.length){ tokens.push(content); } return tokens; }; var Formatter = function(/*String*/ format){ this._mapped = false; this._format = format; this._tokens = tokenize(format, this._re, this._parseDelim, this); }; Formatter.prototype._re = /\%(?:\(([\w_.]+)\)|([1-9]\d*)\$)?([0 +\-\#]*)(\*|\d+)?(\.)?(\*|\d+)?[hlL]?([\%bscdeEfFgGioOuxX])/g; Formatter.prototype._parseDelim = function(mapping, intmapping, flags, minWidth, period, precision, specifier){ if(mapping){ this._mapped = true; } return { mapping: mapping, intmapping: intmapping, flags: flags, _minWidth: minWidth, // May be dependent on parameters period: period, _precision: precision, // May be dependent on parameters specifier: specifier }; }; Formatter.prototype._specifiers = { b: { base: 2, isInt: true }, o: { base: 8, isInt: true }, x: { base: 16, isInt: true }, X: { extend: ['x'], toUpper: true }, d: { base: 10, isInt: true }, i: { extend: ['d'] }, u: { extend: ['d'], isUnsigned: true }, c: { setArg: function(token){ if(!isNaN(token.arg)){ var num = parseInt(token.arg); if(num < 0 || num > 127){ throw new Error('invalid character code passed to %c in printf'); } token.arg = isNaN(num) ? '' + num : String.fromCharCode(num); } } }, s: { setMaxWidth: function(token){ token.maxWidth = (token.period == '.') ? token.precision : -1; } }, e: { isDouble: true, doubleNotation: 'e' }, E: { extend: ['e'], toUpper: true }, f: { isDouble: true, doubleNotation: 'f' }, F: { extend: ['f'] }, g: { isDouble: true, doubleNotation: 'g' }, G: { extend: ['g'], toUpper: true }, O: { isObject: true } }; Formatter.prototype.format = function(/*mixed...*/ filler){ if(this._mapped && typeof filler != 'object'){ throw new Error('format requires a mapping'); } var str = ''; var position = 0; for(var i = 0, token; i < this._tokens.length; i++){ token = this._tokens[i]; if(typeof token == 'string'){ str += token; }else{ if(this._mapped){ // Identify value of property defined in `token.mapping` var tokens = token.mapping.split('.'); var value = filler; for (var j = 0, c = tokens.length; j < c; j++) { value = value[tokens[j]]; if (typeof value === 'undefined') { break } } if(typeof value == 'undefined'){ throw new Error('missing key ' + token.mapping); } token.arg = value; }else{ if(token.intmapping){ position = parseInt(token.intmapping) - 1; } if(position >= arguments.length){ throw new Error('got ' + arguments.length + ' printf arguments, insufficient for \'' + this._format + '\''); } token.arg = arguments[position++]; } if(!token.compiled){ token.compiled = true; token.sign = ''; token.zeroPad = false; token.rightJustify = false; token.alternative = false; var flags = {}; for(var fi = token.flags.length; fi--;){ var flag = token.flags.charAt(fi); flags[flag] = true; switch(flag){ case ' ': token.sign = ' '; break; case '+': token.sign = '+'; break; case '0': token.zeroPad = (flags['-']) ? false : true; break; case '-': token.rightJustify = true; token.zeroPad = false; break; case '#': token.alternative = true; break; default: throw Error('bad formatting flag \'' + token.flags.charAt(fi) + '\''); } } token.minWidth = (token._minWidth) ? parseInt(token._minWidth) : 0; token.maxWidth = -1; token.toUpper = false; token.isUnsigned = false; token.isInt = false; token.isDouble = false; token.isObject = false; token.precision = 1; if(token.period == '.'){ if(token._precision){ token.precision = parseInt(token._precision); }else{ token.precision = 0; } } var mixins = this._specifiers[token.specifier]; if(typeof mixins == 'undefined'){ throw new Error('unexpected specifier \'' + token.specifier + '\''); } if(mixins.extend){ var s = this._specifiers[mixins.extend]; for(var k in s){ mixins[k] = s[k]; } delete mixins.extend; } for(var l in mixins){ token[l] = mixins[l]; } } if(typeof token.setArg == 'function'){ token.setArg(token); } if(typeof token.setMaxWidth == 'function'){ token.setMaxWidth(token); } if(token._minWidth == '*'){ if(this._mapped){ throw new Error('* width not supported in mapped formats'); } token.minWidth = parseInt(arguments[position++]); if(isNaN(token.minWidth)){ throw new Error('the argument for * width at position ' + position + ' is not a number in ' + this._format); } // negative width means rightJustify if (token.minWidth < 0) { token.rightJustify = true; token.minWidth = -token.minWidth; } } if(token._precision == '*' && token.period == '.'){ if(this._mapped){ throw new Error('* precision not supported in mapped formats'); } token.precision = parseInt(arguments[position++]); if(isNaN(token.precision)){ throw Error('the argument for * precision at position ' + position + ' is not a number in ' + this._format); } // negative precision means unspecified if (token.precision < 0) { token.precision = 1; token.period = ''; } } if(token.isInt){ // a specified precision means no zero padding if(token.period == '.'){ token.zeroPad = false; } this.formatInt(token); }else if(token.isDouble){ if(token.period != '.'){ token.precision = 6; } this.formatDouble(token); }else if(token.isObject){ this.formatObject(token); } this.fitField(token); str += '' + token.arg; } } return str; }; Formatter.prototype._zeros10 = '0000000000'; Formatter.prototype._spaces10 = ' '; Formatter.prototype.formatInt = function(token) { var i = parseInt(token.arg); if(!isFinite(i)){ // isNaN(f) || f == Number.POSITIVE_INFINITY || f == Number.NEGATIVE_INFINITY) // allow this only if arg is number if(typeof token.arg != 'number'){ throw new Error('format argument \'' + token.arg + '\' not an integer; parseInt returned ' + i); } //return '' + i; i = 0; } // if not base 10, make negatives be positive // otherwise, (-10).toString(16) is '-a' instead of 'fffffff6' if(i < 0 && (token.isUnsigned || token.base != 10)){ i = 0xffffffff + i + 1; } if(i < 0){ token.arg = (- i).toString(token.base); this.zeroPad(token); token.arg = '-' + token.arg; }else{ token.arg = i.toString(token.base); // need to make sure that argument 0 with precision==0 is formatted as '' if(!i && !token.precision){ token.arg = ''; }else{ this.zeroPad(token); } if(token.sign){ token.arg = token.sign + token.arg; } } if(token.base == 16){ if(token.alternative){ token.arg = '0x' + token.arg; } token.arg = token.toUpper ? token.arg.toUpperCase() : token.arg.toLowerCase(); } if(token.base == 8){ if(token.alternative && token.arg.charAt(0) != '0'){ token.arg = '0' + token.arg; } } }; Formatter.prototype.formatDouble = function(token) { var f = parseFloat(token.arg); if(!isFinite(f)){ // isNaN(f) || f == Number.POSITIVE_INFINITY || f == Number.NEGATIVE_INFINITY) // allow this only if arg is number if(typeof token.arg != 'number'){ throw new Error('format argument \'' + token.arg + '\' not a float; parseFloat returned ' + f); } // C99 says that for 'f': // infinity -> '[-]inf' or '[-]infinity' ('[-]INF' or '[-]INFINITY' for 'F') // NaN -> a string starting with 'nan' ('NAN' for 'F') // this is not commonly implemented though. //return '' + f; f = 0; } switch(token.doubleNotation) { case 'e': { token.arg = f.toExponential(token.precision); break; } case 'f': { token.arg = f.toFixed(token.precision); break; } case 'g': { // C says use 'e' notation if exponent is < -4 or is >= prec // ECMAScript for toPrecision says use exponential notation if exponent is >= prec, // though step 17 of toPrecision indicates a test for < -6 to force exponential. if(Math.abs(f) < 0.0001){ //print('forcing exponential notation for f=' + f); token.arg = f.toExponential(token.precision > 0 ? token.precision - 1 : token.precision); }else{ token.arg = f.toPrecision(token.precision); } // In C, unlike 'f', 'gG' removes trailing 0s from fractional part, unless alternative format flag ('#'). // But ECMAScript formats toPrecision as 0.00100000. So remove trailing 0s. if(!token.alternative){ //print('replacing trailing 0 in \'' + s + '\''); token.arg = token.arg.replace(/(\..*[^0])0*e/, '$1e'); // if fractional part is entirely 0, remove it and decimal point token.arg = token.arg.replace(/\.0*e/, 'e').replace(/\.0$/,''); } break; } default: throw new Error('unexpected double notation \'' + token.doubleNotation + '\''); } // C says that exponent must have at least two digits. // But ECMAScript does not; toExponential results in things like '1.000000e-8' and '1.000000e+8'. // Note that s.replace(/e([\+\-])(\d)/, 'e$10$2') won't work because of the '$10' instead of '$1'. // And replace(re, func) isn't supported on IE50 or Safari1. token.arg = token.arg.replace(/e\+(\d)$/, 'e+0$1').replace(/e\-(\d)$/, 'e-0$1'); // if alt, ensure a decimal point if(token.alternative){ token.arg = token.arg.replace(/^(\d+)$/,'$1.'); token.arg = token.arg.replace(/^(\d+)e/,'$1.e'); } if(f >= 0 && token.sign){ token.arg = token.sign + token.arg; } token.arg = token.toUpper ? token.arg.toUpperCase() : token.arg.toLowerCase(); }; Formatter.prototype.formatObject = function(token) { // If no precision is specified, then reset it to null (infinite depth). var precision = (token.period === '.') ? token.precision : null; token.arg = util.inspect(token.arg, !token.alternative, precision); }; Formatter.prototype.zeroPad = function(token, /*Int*/ length) { length = (arguments.length == 2) ? length : token.precision; var negative = false; if(typeof token.arg != "string"){ token.arg = "" + token.arg; } if (token.arg.substr(0,1) === '-') { negative = true; token.arg = token.arg.substr(1); } var tenless = length - 10; while(token.arg.length < tenless){ token.arg = (token.rightJustify) ? token.arg + this._zeros10 : this._zeros10 + token.arg; } var pad = length - token.arg.length; token.arg = (token.rightJustify) ? token.arg + this._zeros10.substring(0, pad) : this._zeros10.substring(0, pad) + token.arg; if (negative) token.arg = '-' + token.arg; }; Formatter.prototype.fitField = function(token) { if(token.maxWidth >= 0 && token.arg.length > token.maxWidth){ return token.arg.substring(0, token.maxWidth); } if(token.zeroPad){ this.zeroPad(token, token.minWidth); return; } this.spacePad(token); }; Formatter.prototype.spacePad = function(token, /*Int*/ length) { length = (arguments.length == 2) ? length : token.minWidth; if(typeof token.arg != 'string'){ token.arg = '' + token.arg; } var tenless = length - 10; while(token.arg.length < tenless){ token.arg = (token.rightJustify) ? token.arg + this._spaces10 : this._spaces10 + token.arg; } var pad = length - token.arg.length; token.arg = (token.rightJustify) ? token.arg + this._spaces10.substring(0, pad) : this._spaces10.substring(0, pad) + token.arg; }; module.exports = function(){ var args = Array.prototype.slice.call(arguments), stream, format; if(args[0] instanceof require('stream').Stream){ stream = args.shift(); } format = args.shift(); var formatter = new Formatter(format); var string = formatter.format.apply(formatter, args); if(stream){ stream.write(string); }else{ return string; } }; module.exports.Formatter = Formatter;