bits-ui
Version:
The headless components for Svelte.
60 lines (59 loc) • 2.56 kB
JavaScript
/**
* https://github.com/mathiasbynens/CSS.escape
*
* @param value - The value to escape for use as a CSS identifier
* @returns The escaped CSS identifier string
*/
export function cssEscape(value) {
if (typeof CSS !== "undefined" && typeof CSS.escape === "function") {
return CSS.escape(value);
}
const length = value.length;
let index = -1;
let codeUnit;
let result = "";
const firstCodeUnit = value.charCodeAt(0);
// If the character is the first character and is a `-` (U+002D), and
// there is no second character, escape it
if (length === 1 && firstCodeUnit === 0x002d)
return "\\" + value;
while (++index < length) {
codeUnit = value.charCodeAt(index);
// If the character is NULL (U+0000), then the REPLACEMENT CHARACTER (U+FFFD)
if (codeUnit === 0x0000) {
result += "\uFFFD";
continue;
}
if (
// If the character is in the range [\1-\1F] (U+0001 to U+001F) or is U+007F
(codeUnit >= 0x0001 && codeUnit <= 0x001f) ||
codeUnit === 0x007f ||
// If the character is the first character and is in the range [0-9] (U+0030 to U+0039)
(index === 0 && codeUnit >= 0x0030 && codeUnit <= 0x0039) ||
// If the character is the second character and is in the range [0-9] (U+0030 to U+0039)
// and the first character is a `-` (U+002D)
(index === 1 && codeUnit >= 0x0030 && codeUnit <= 0x0039 && firstCodeUnit === 0x002d)) {
// https://drafts.csswg.org/cssom/#escape-a-character-as-code-point
result += "\\" + codeUnit.toString(16) + " ";
continue;
}
// If the character is not handled by one of the above rules and is
// greater than or equal to U+0080, is `-` (U+002D) or `_` (U+005F), or
// is in one of the ranges [0-9] (U+0030 to U+0039), [A-Z] (U+0041 to U+005A),
// or [a-z] (U+0061 to U+007A)
if (codeUnit >= 0x0080 ||
codeUnit === 0x002d ||
codeUnit === 0x005f ||
(codeUnit >= 0x0030 && codeUnit <= 0x0039) ||
(codeUnit >= 0x0041 && codeUnit <= 0x005a) ||
(codeUnit >= 0x0061 && codeUnit <= 0x007a)) {
// Use the character itself
result += value.charAt(index);
continue;
}
// Otherwise, escape the character
// https://drafts.csswg.org/cssom/#escape-a-character
result += "\\" + value.charAt(index);
}
return result;
}