time-to-botec/squiggle/node_modules/@stdlib/string/percent-encode/lib/percent_encode.js
NunoSempere b6addc7f05 feat: add the node modules
Necessary in order to clearly see the squiggle hotwiring.
2022-12-03 12:44:49 +00:00

107 lines
2.5 KiB
JavaScript

/**
* @license Apache-2.0
*
* Copyright (c) 2018 The Stdlib Authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
'use strict';
// MODULES //
var isString = require( '@stdlib/assert/is-string' ).isPrimitive;
var utf16ToUTF8Array = require( './../../utf16-to-utf8-array' );
var format = require( './../../format' );
// VARIABLES //
// Character codes:
var UNDERSCORE = 95|0;
var PERIOD = 46|0;
var HYPHEN = 45|0;
var TILDE = 126|0;
var ZERO = 48|0;
var NINE = 57|0;
var A = 65|0;
var Z = 90|0;
var a = 97|0;
var z = 122|0;
// MAIN //
/**
* Percent-encode a UTF-16 encoded string according to [RFC 3986][1].
*
* [1]: https://tools.ietf.org/html/rfc3986#section-2.1
*
* @param {string} str - string to percent-encode
* @throws {TypeError} must provide a string
* @returns {string} percent-encoded string
*
* @example
* var str1 = 'Ladies + Gentlemen';
*
* var str2 = percentEncode( str1 );
* // returns 'Ladies%20%2B%20Gentlemen'
*/
function percentEncode( str ) {
var byte;
var out;
var len;
var buf;
var i;
if ( !isString( str ) ) {
throw new TypeError( format( 'invalid argument. Must provide a string. Value: `%s`.', str ) );
}
// Convert to an array of octets using UTF-8 encoding (see https://tools.ietf.org/html/rfc3986#section-2.5):
buf = utf16ToUTF8Array( str );
// Encode the string...
len = buf.length;
out = '';
for ( i = 0; i < len; i++ ) {
byte = buf[ i ];
if (
// ASCII Digits:
( byte >= ZERO && byte <= NINE ) ||
// ASCII uppercase letters:
( byte >= A && byte <= Z ) ||
// ASCII lowercase letters:
( byte >= a && byte <= z ) ||
// ASCII unreserved characters (see https://tools.ietf.org/html/rfc3986#section-2.3):
byte === HYPHEN ||
byte === PERIOD ||
byte === UNDERSCORE ||
byte === TILDE
) {
out += str.charAt( i );
} else {
// Convert an octet to hexadecimal and uppercase according to the RFC (see https://tools.ietf.org/html/rfc3986#section-2.1):
out += '%' + byte.toString( 16 ).toUpperCase();
}
}
return out;
}
// EXPORTS //
module.exports = percentEncode;