site/node_modules/stringify-entities/lib/util/format-smart.js
2024-10-14 08:09:33 +02:00

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/**
* @typedef FormatSmartOptions
* @property {boolean} [useNamedReferences=false]
* Prefer named character references (`&`) where possible.
* @property {boolean} [useShortestReferences=false]
* Prefer the shortest possible reference, if that results in less bytes.
* **Note**: `useNamedReferences` can be omitted when using `useShortestReferences`.
* @property {boolean} [omitOptionalSemicolons=false]
* Whether to omit semicolons when possible.
* **Note**: This creates what HTML calls “parse errors” but is otherwise still valid HTML — dont use this except when building a minifier.
* Omitting semicolons is possible for certain named and numeric references in some cases.
* @property {boolean} [attribute=false]
* Create character references which dont fail in attributes.
* **Note**: `attribute` only applies when operating dangerously with
* `omitOptionalSemicolons: true`.
*/
import {toHexadecimal} from './to-hexadecimal.js'
import {toDecimal} from './to-decimal.js'
import {toNamed} from './to-named.js'
/**
* Configurable ways to encode a character yielding pretty or small results.
*
* @param {number} code
* @param {number} next
* @param {FormatSmartOptions} options
* @returns {string}
*/
export function formatSmart(code, next, options) {
let numeric = toHexadecimal(code, next, options.omitOptionalSemicolons)
/** @type {string|undefined} */
let named
if (options.useNamedReferences || options.useShortestReferences) {
named = toNamed(
code,
next,
options.omitOptionalSemicolons,
options.attribute
)
}
// Use the shortest numeric reference when requested.
// A simple algorithm would use decimal for all code points under 100, as
// those are shorter than hexadecimal:
//
// * `c` vs `c` (decimal shorter)
// * `d` vs `d` (equal)
//
// However, because we take `next` into consideration when `omit` is used,
// And it would be possible that decimals are shorter on bigger values as
// well if `next` is hexadecimal but not decimal, we instead compare both.
if (
(options.useShortestReferences || !named) &&
options.useShortestReferences
) {
const decimal = toDecimal(code, next, options.omitOptionalSemicolons)
if (decimal.length < numeric.length) {
numeric = decimal
}
}
return named &&
(!options.useShortestReferences || named.length < numeric.length)
? named
: numeric
}