site/node_modules/micromark-util-decode-string/dev/index.js

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2024-10-14 06:09:33 +00:00
import {decodeNamedCharacterReference} from 'decode-named-character-reference'
import {decodeNumericCharacterReference} from 'micromark-util-decode-numeric-character-reference'
import {codes, constants} from 'micromark-util-symbol'
const characterEscapeOrReference =
/\\([!-/:-@[-`{-~])|&(#(?:\d{1,7}|x[\da-f]{1,6})|[\da-z]{1,31});/gi
/**
* Decode markdown strings (which occur in places such as fenced code info
* strings, destinations, labels, and titles).
*
* The string content type allows character escapes and -references.
* This decodes those.
*
* @param {string} value
* Value to decode.
* @returns {string}
* Decoded value.
*/
export function decodeString(value) {
return value.replace(characterEscapeOrReference, decode)
}
/**
* @param {string} $0
* @param {string} $1
* @param {string} $2
* @returns {string}
*/
function decode($0, $1, $2) {
if ($1) {
// Escape.
return $1
}
// Reference.
const head = $2.charCodeAt(0)
if (head === codes.numberSign) {
const head = $2.charCodeAt(1)
const hex = head === codes.lowercaseX || head === codes.uppercaseX
return decodeNumericCharacterReference(
$2.slice(hex ? 2 : 1),
hex ? constants.numericBaseHexadecimal : constants.numericBaseDecimal
)
}
return decodeNamedCharacterReference($2) || $0
}