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// Copyright 2018-2023 the Deno authors. All rights reserved. MIT license.// Copyright Joyent, Inc. and other Node contributors.//// Permission is hereby granted, free of charge, to any person obtaining a// copy of this software and associated documentation files (the// "Software"), to deal in the Software without restriction, including// without limitation the rights to use, copy, modify, merge, publish,// distribute, sublicense, and/or sell copies of the Software, and to permit// persons to whom the Software is furnished to do so, subject to the// following conditions://// The above copyright notice and this permission notice shall be included// in all copies or substantial portions of the Software.//// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE// USE OR OTHER DEALINGS IN THE SOFTWARE.
// Copyright Mathias Bynens <https://mathiasbynens.be/>
// Permission is hereby granted, free of charge, to any person obtaining// a copy of this software and associated documentation files (the// "Software"), to deal in the Software without restriction, including// without limitation the rights to use, copy, modify, merge, publish,// distribute, sublicense, and/or sell copies of the Software, and to// permit persons to whom the Software is furnished to do so, subject to// the following conditions:
// The above copyright notice and this permission notice shall be// included in all copies or substantial portions of the Software.
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
// Adapted from https://github.com/mathiasbynens/punycode.js
// TODO(cmorten): migrate punycode logic to "icu" internal binding and/or "url"// internal module so there can be re-use within the "url" module etc.
"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; // 0x80const delimiter = "-"; // '\x2D'
/** Regular expressions */export const regexPunycode = /^xn--/;export const regexNonASCII = /[^\0-\x7E]/; // non-ASCII charsconst regexSeparators = /[\x2E\u3002\uFF0E\uFF61]/g; // RFC 3490 separators
/** Error messages */const errors: Record<string, string> = { "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;
/** * A generic error utility function. * * @param type The error type. * @return Throws a `RangeError` with the applicable error message. */function error(type: string) { throw new RangeError(errors[type]);}
/** * A simple `Array#map`-like wrapper to work with domain name strings or email * addresses. * * @param domain The domain name or email address. * @param callback The function that gets called for every * character. * @return A new string of characters returned by the callback * function. */function mapDomain(str: string, fn: (label: string) => string) { const parts = str.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] + "@"; str = parts[1]; }
// Avoid `split(regex)` for IE8 compatibility. See #17. str = str.replace(regexSeparators, "\x2E"); const labels = str.split("."); const encoded = labels.map(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. * * @param str The Unicode input string (UCS-2). * @return The new array of code points. */function ucs2decode(str: string) { const output = []; let counter = 0; const length = str.length;
while (counter < length) { const value = str.charCodeAt(counter++);
if (value >= 0xD800 && value <= 0xDBFF && counter < length) { // It's a high surrogate, and there is a next character. const extra = str.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 codePoints The array of numeric code points. * @returns The new Unicode string (UCS-2). */function ucs2encode(array: number[]) { return String.fromCodePoint(...array);}
export const ucs2 = { decode: ucs2decode, encode: ucs2encode,};
/** * Converts a basic code point into a digit/integer. * @see `digitToBasic()` * @private * @param codePoint The basic numeric code point value. * @returns 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. */function basicToDigit(codePoint: number) { 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. * * @param digit The numeric value of a basic code point. * @return 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. */function digitToBasic(digit: number, flag: number) { // 0..25 map to ASCII a..z or A..Z // 26..35 map to ASCII 0..9 return digit + 22 + 75 * Number(digit < 26) - (Number(flag != 0) << 5);}
/** * Bias adaptation function as per section 3.4 of RFC 3492. * https://tools.ietf.org/html/rfc3492#section-3.4 */function adapt(delta: number, numPoints: number, firstTime: boolean) { let k = 0; delta = firstTime ? Math.floor(delta / damp) : delta >> 1; delta += Math.floor(delta / numPoints);
for (; /* no initialization */ delta > baseMinusTMin * tMax >> 1; k += base) { delta = Math.floor(delta / baseMinusTMin); }
return Math.floor(k + (baseMinusTMin + 1) * delta / (delta + skew));}
/** * Converts a Punycode string of ASCII-only symbols to a string of Unicode * symbols. * @memberOf punycode * @param input The Punycode string of ASCII-only symbols. * @returns The resulting string of Unicode symbols. */export function decode(input: string): string { // 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`. const 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. * * @param str The string of Unicode symbols. * @return The resulting Punycode string of ASCII-only symbols. */export function encode(str: string) { const output = [];
// Convert the input in UCS-2 to an array of Unicode code points. const input = ucs2decode(str);
// Cache the length. const 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(String.fromCharCode(currentValue)); } }
const 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 > Math.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( String.fromCharCode(digitToBasic(t + qMinusT % baseMinusT, 0)), );
q = Math.floor(qMinusT / baseMinusT); }
output.push(String.fromCharCode(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 input The Punycoded domain name or email address to * convert to Unicode. * @returns The Unicode representation of the given Punycode * string. */export function toUnicode(input: string) { 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. * * @param input The domain name or email address to convert, as a * Unicode string. * @return The Punycode representation of the given domain name or * email address. */export function toASCII(input: string): string { return mapDomain(input, function (str: string) { return regexNonASCII.test(str) ? "xn--" + encode(str) : str; });}