/node_modules/punycode/punycode.js
JavaScript | 440 lines | 222 code | 56 blank | 162 comment | 43 complexity | 5276136dbaa8b6df7fcacf76cb06d315 MD5 | raw file
- 'use strict';
- /** Highest positive signed 32-bit float value */
- const maxInt = 2147483647; // aka. 0x7FFFFFFF or 2^31-1
- /** Bootstring parameters */
- const base = 36;
- const tMin = 1;
- const tMax = 26;
- const skew = 38;
- const damp = 700;
- const initialBias = 72;
- const initialN = 128; // 0x80
- const delimiter = '-'; // '\x2D'
- /** Regular expressions */
- const regexPunycode = /^xn--/;
- const regexNonASCII = /[^\0-\x7E]/; // non-ASCII chars
- const regexSeparators = /[\x2E\u3002\uFF0E\uFF61]/g; // RFC 3490 separators
- /** Error messages */
- const errors = {
- 'overflow': 'Overflow: input needs wider integers to process',
- 'not-basic': 'Illegal input >= 0x80 (not a basic code point)',
- 'invalid-input': 'Invalid input'
- };
- /** Convenience shortcuts */
- const baseMinusTMin = base - tMin;
- const floor = Math.floor;
- const stringFromCharCode = String.fromCharCode;
- /*--------------------------------------------------------------------------*/
- /**
- * A generic error utility function.
- * @private
- * @param {String} type The error type.
- * @returns {Error} Throws a `RangeError` with the applicable error message.
- */
- function error(type) {
- throw new RangeError(errors[type]);
- }
- /**
- * A generic `Array#map` utility function.
- * @private
- * @param {Array} array The array to iterate over.
- * @param {Function} callback The function that gets called for every array
- * item.
- * @returns {Array} A new array of values returned by the callback function.
- */
- function map(array, fn) {
- const result = [];
- let length = array.length;
- while (length--) {
- result[length] = fn(array[length]);
- }
- return result;
- }
- /**
- * A simple `Array#map`-like wrapper to work with domain name strings or email
- * addresses.
- * @private
- * @param {String} domain The domain name or email address.
- * @param {Function} callback The function that gets called for every
- * character.
- * @returns {Array} A new string of characters returned by the callback
- * function.
- */
- function mapDomain(string, fn) {
- const parts = string.split('@');
- let result = '';
- if (parts.length > 1) {
- // In email addresses, only the domain name should be punycoded. Leave
- // the local part (i.e. everything up to `@`) intact.
- result = parts[0] + '@';
- string = parts[1];
- }
- // Avoid `split(regex)` for IE8 compatibility. See #17.
- string = string.replace(regexSeparators, '\x2E');
- const labels = string.split('.');
- const encoded = map(labels, fn).join('.');
- return result + encoded;
- }
- /**
- * Creates an array containing the numeric code points of each Unicode
- * character in the string. While JavaScript uses UCS-2 internally,
- * this function will convert a pair of surrogate halves (each of which
- * UCS-2 exposes as separate characters) into a single code point,
- * matching UTF-16.
- * @see `punycode.ucs2.encode`
- * @see <https://mathiasbynens.be/notes/javascript-encoding>
- * @memberOf punycode.ucs2
- * @name decode
- * @param {String} string The Unicode input string (UCS-2).
- * @returns {Array} The new array of code points.
- */
- function ucs2decode(string) {
- const output = [];
- let counter = 0;
- const length = string.length;
- while (counter < length) {
- const value = string.charCodeAt(counter++);
- if (value >= 0xD800 && value <= 0xDBFF && counter < length) {
- // It's a high surrogate, and there is a next character.
- const extra = string.charCodeAt(counter++);
- if ((extra & 0xFC00) == 0xDC00) { // Low surrogate.
- output.push(((value & 0x3FF) << 10) + (extra & 0x3FF) + 0x10000);
- } else {
- // It's an unmatched surrogate; only append this code unit, in case the
- // next code unit is the high surrogate of a surrogate pair.
- output.push(value);
- counter--;
- }
- } else {
- output.push(value);
- }
- }
- return output;
- }
- /**
- * Creates a string based on an array of numeric code points.
- * @see `punycode.ucs2.decode`
- * @memberOf punycode.ucs2
- * @name encode
- * @param {Array} codePoints The array of numeric code points.
- * @returns {String} The new Unicode string (UCS-2).
- */
- const ucs2encode = array => String.fromCodePoint(...array);
- /**
- * Converts a basic code point into a digit/integer.
- * @see `digitToBasic()`
- * @private
- * @param {Number} codePoint The basic numeric code point value.
- * @returns {Number} The numeric value of a basic code point (for use in
- * representing integers) in the range `0` to `base - 1`, or `base` if
- * the code point does not represent a value.
- */
- const basicToDigit = function(codePoint) {
- if (codePoint - 0x30 < 0x0A) {
- return codePoint - 0x16;
- }
- if (codePoint - 0x41 < 0x1A) {
- return codePoint - 0x41;
- }
- if (codePoint - 0x61 < 0x1A) {
- return codePoint - 0x61;
- }
- return base;
- };
- /**
- * Converts a digit/integer into a basic code point.
- * @see `basicToDigit()`
- * @private
- * @param {Number} digit The numeric value of a basic code point.
- * @returns {Number} The basic code point whose value (when used for
- * representing integers) is `digit`, which needs to be in the range
- * `0` to `base - 1`. If `flag` is non-zero, the uppercase form is
- * used; else, the lowercase form is used. The behavior is undefined
- * if `flag` is non-zero and `digit` has no uppercase form.
- */
- const digitToBasic = function(digit, flag) {
- // 0..25 map to ASCII a..z or A..Z
- // 26..35 map to ASCII 0..9
- return digit + 22 + 75 * (digit < 26) - ((flag != 0) << 5);
- };
- /**
- * Bias adaptation function as per section 3.4 of RFC 3492.
- * https://tools.ietf.org/html/rfc3492#section-3.4
- * @private
- */
- const adapt = function(delta, numPoints, firstTime) {
- let k = 0;
- delta = firstTime ? floor(delta / damp) : delta >> 1;
- delta += floor(delta / numPoints);
- for (/* no initialization */; delta > baseMinusTMin * tMax >> 1; k += base) {
- delta = floor(delta / baseMinusTMin);
- }
- return floor(k + (baseMinusTMin + 1) * delta / (delta + skew));
- };
- /**
- * Converts a Punycode string of ASCII-only symbols to a string of Unicode
- * symbols.
- * @memberOf punycode
- * @param {String} input The Punycode string of ASCII-only symbols.
- * @returns {String} The resulting string of Unicode symbols.
- */
- const decode = function(input) {
- // Don't use UCS-2.
- const output = [];
- const inputLength = input.length;
- let i = 0;
- let n = initialN;
- let bias = initialBias;
- // Handle the basic code points: let `basic` be the number of input code
- // points before the last delimiter, or `0` if there is none, then copy
- // the first basic code points to the output.
- let basic = input.lastIndexOf(delimiter);
- if (basic < 0) {
- basic = 0;
- }
- for (let j = 0; j < basic; ++j) {
- // if it's not a basic code point
- if (input.charCodeAt(j) >= 0x80) {
- error('not-basic');
- }
- output.push(input.charCodeAt(j));
- }
- // Main decoding loop: start just after the last delimiter if any basic code
- // points were copied; start at the beginning otherwise.
- for (let index = basic > 0 ? basic + 1 : 0; index < inputLength; /* no final expression */) {
- // `index` is the index of the next character to be consumed.
- // Decode a generalized variable-length integer into `delta`,
- // which gets added to `i`. The overflow checking is easier
- // if we increase `i` as we go, then subtract off its starting
- // value at the end to obtain `delta`.
- let oldi = i;
- for (let w = 1, k = base; /* no condition */; k += base) {
- if (index >= inputLength) {
- error('invalid-input');
- }
- const digit = basicToDigit(input.charCodeAt(index++));
- if (digit >= base || digit > floor((maxInt - i) / w)) {
- error('overflow');
- }
- i += digit * w;
- const t = k <= bias ? tMin : (k >= bias + tMax ? tMax : k - bias);
- if (digit < t) {
- break;
- }
- const baseMinusT = base - t;
- if (w > floor(maxInt / baseMinusT)) {
- error('overflow');
- }
- w *= baseMinusT;
- }
- const out = output.length + 1;
- bias = adapt(i - oldi, out, oldi == 0);
- // `i` was supposed to wrap around from `out` to `0`,
- // incrementing `n` each time, so we'll fix that now:
- if (floor(i / out) > maxInt - n) {
- error('overflow');
- }
- n += floor(i / out);
- i %= out;
- // Insert `n` at position `i` of the output.
- output.splice(i++, 0, n);
- }
- return String.fromCodePoint(...output);
- };
- /**
- * Converts a string of Unicode symbols (e.g. a domain name label) to a
- * Punycode string of ASCII-only symbols.
- * @memberOf punycode
- * @param {String} input The string of Unicode symbols.
- * @returns {String} The resulting Punycode string of ASCII-only symbols.
- */
- const encode = function(input) {
- const output = [];
- // Convert the input in UCS-2 to an array of Unicode code points.
- input = ucs2decode(input);
- // Cache the length.
- let inputLength = input.length;
- // Initialize the state.
- let n = initialN;
- let delta = 0;
- let bias = initialBias;
- // Handle the basic code points.
- for (const currentValue of input) {
- if (currentValue < 0x80) {
- output.push(stringFromCharCode(currentValue));
- }
- }
- let basicLength = output.length;
- let handledCPCount = basicLength;
- // `handledCPCount` is the number of code points that have been handled;
- // `basicLength` is the number of basic code points.
- // Finish the basic string with a delimiter unless it's empty.
- if (basicLength) {
- output.push(delimiter);
- }
- // Main encoding loop:
- while (handledCPCount < inputLength) {
- // All non-basic code points < n have been handled already. Find the next
- // larger one:
- let m = maxInt;
- for (const currentValue of input) {
- if (currentValue >= n && currentValue < m) {
- m = currentValue;
- }
- }
- // Increase `delta` enough to advance the decoder's <n,i> state to <m,0>,
- // but guard against overflow.
- const handledCPCountPlusOne = handledCPCount + 1;
- if (m - n > floor((maxInt - delta) / handledCPCountPlusOne)) {
- error('overflow');
- }
- delta += (m - n) * handledCPCountPlusOne;
- n = m;
- for (const currentValue of input) {
- if (currentValue < n && ++delta > maxInt) {
- error('overflow');
- }
- if (currentValue == n) {
- // Represent delta as a generalized variable-length integer.
- let q = delta;
- for (let k = base; /* no condition */; k += base) {
- const t = k <= bias ? tMin : (k >= bias + tMax ? tMax : k - bias);
- if (q < t) {
- break;
- }
- const qMinusT = q - t;
- const baseMinusT = base - t;
- output.push(
- stringFromCharCode(digitToBasic(t + qMinusT % baseMinusT, 0))
- );
- q = floor(qMinusT / baseMinusT);
- }
- output.push(stringFromCharCode(digitToBasic(q, 0)));
- bias = adapt(delta, handledCPCountPlusOne, handledCPCount == basicLength);
- delta = 0;
- ++handledCPCount;
- }
- }
- ++delta;
- ++n;
- }
- return output.join('');
- };
- /**
- * Converts a Punycode string representing a domain name or an email address
- * to Unicode. Only the Punycoded parts of the input will be converted, i.e.
- * it doesn't matter if you call it on a string that has already been
- * converted to Unicode.
- * @memberOf punycode
- * @param {String} input The Punycoded domain name or email address to
- * convert to Unicode.
- * @returns {String} The Unicode representation of the given Punycode
- * string.
- */
- const toUnicode = function(input) {
- return mapDomain(input, function(string) {
- return regexPunycode.test(string)
- ? decode(string.slice(4).toLowerCase())
- : string;
- });
- };
- /**
- * Converts a Unicode string representing a domain name or an email address to
- * Punycode. Only the non-ASCII parts of the domain name will be converted,
- * i.e. it doesn't matter if you call it with a domain that's already in
- * ASCII.
- * @memberOf punycode
- * @param {String} input The domain name or email address to convert, as a
- * Unicode string.
- * @returns {String} The Punycode representation of the given domain name or
- * email address.
- */
- const toASCII = function(input) {
- return mapDomain(input, function(string) {
- return regexNonASCII.test(string)
- ? 'xn--' + encode(string)
- : string;
- });
- };
- /*--------------------------------------------------------------------------*/
- /** Define the public API */
- const punycode = {
- /**
- * A string representing the current Punycode.js version number.
- * @memberOf punycode
- * @type String
- */
- 'version': '2.1.0',
- /**
- * An object of methods to convert from JavaScript's internal character
- * representation (UCS-2) to Unicode code points, and back.
- * @see <https://mathiasbynens.be/notes/javascript-encoding>
- * @memberOf punycode
- * @type Object
- */
- 'ucs2': {
- 'decode': ucs2decode,
- 'encode': ucs2encode
- },
- 'decode': decode,
- 'encode': encode,
- 'toASCII': toASCII,
- 'toUnicode': toUnicode
- };
- module.exports = punycode;