in src/internal/qs/utils.ts [136:213]
export const encode: (
str: any,
defaultEncoder: DefaultEncoder,
charset: string,
type: 'key' | 'value',
format: Format,
) => string = (str, _defaultEncoder, charset, _kind, format: Format) => {
// This code was originally written by Brian White for the io.js core querystring library.
// It has been adapted here for stricter adherence to RFC 3986
if (str.length === 0) {
return str;
}
let string = str;
if (typeof str === 'symbol') {
string = Symbol.prototype.toString.call(str);
} else if (typeof str !== 'string') {
string = String(str);
}
if (charset === 'iso-8859-1') {
return escape(string).replace(/%u[0-9a-f]{4}/gi, function ($0) {
return '%26%23' + parseInt($0.slice(2), 16) + '%3B';
});
}
let out = '';
for (let j = 0; j < string.length; j += limit) {
const segment = string.length >= limit ? string.slice(j, j + limit) : string;
const arr = [];
for (let i = 0; i < segment.length; ++i) {
let c = segment.charCodeAt(i);
if (
c === 0x2d || // -
c === 0x2e || // .
c === 0x5f || // _
c === 0x7e || // ~
(c >= 0x30 && c <= 0x39) || // 0-9
(c >= 0x41 && c <= 0x5a) || // a-z
(c >= 0x61 && c <= 0x7a) || // A-Z
(format === RFC1738 && (c === 0x28 || c === 0x29)) // ( )
) {
arr[arr.length] = segment.charAt(i);
continue;
}
if (c < 0x80) {
arr[arr.length] = hex_table[c];
continue;
}
if (c < 0x800) {
arr[arr.length] = hex_table[0xc0 | (c >> 6)]! + hex_table[0x80 | (c & 0x3f)];
continue;
}
if (c < 0xd800 || c >= 0xe000) {
arr[arr.length] =
hex_table[0xe0 | (c >> 12)]! + hex_table[0x80 | ((c >> 6) & 0x3f)] + hex_table[0x80 | (c & 0x3f)];
continue;
}
i += 1;
c = 0x10000 + (((c & 0x3ff) << 10) | (segment.charCodeAt(i) & 0x3ff));
arr[arr.length] =
hex_table[0xf0 | (c >> 18)]! +
hex_table[0x80 | ((c >> 12) & 0x3f)] +
hex_table[0x80 | ((c >> 6) & 0x3f)] +
hex_table[0x80 | (c & 0x3f)];
}
out += arr.join('');
}
return out;
};