Function consumeAFunction

lib/css/syntax.js:2797–2826

(ts)

 * @returns {FunctionNode | undefined} the consumed function node
 */
const consumeAFunction = (ts) => {
	const { input } = ts;
	// Assert (spec): the next token is a <function-token>.
	// Consume a token from input, and let function be a new function with its name equal the returned token’s value, and a value set to an empty list.
	const tFn = ts.consume();
	const fn = /** @type {FunctionNode} */ (
		_mkContainer(T_FUNCTION, tFn.start, tFn.end)
	);
	_setName(fn, input.slice(tFn.start, tFn.end - 1), tFn.start, tFn.end - 1);
	const val = _list();
	_setValue(fn, val);

	// Process input
	for (;;) {
		const t = ts.next();

		if (t.type === TT_EOF || t.type === TT_RIGHT_PARENTHESIS) {
			// <eof-token>
			// <)-token>
			// Discard a token from input. Return function.
			ts.discard();
			_setEnd(fn, t.end);
			return fn;
		}

		// anything else
		// Consume a component value from input and append the result to function’s value.
		val.push(consumeAComponentValue(ts, t));
	}
};

// Identifier escape / unescape — operate on the raw text of an
// `<ident-token>` (or any source slice that may carry CSS escape sequences).