bracket.js — svelte Source File

Source Code

/** @import { Parser } from '../index.js' */
import * as e from '../../../errors.js';

/**
 * @param {number} num
 * @returns {number} Infinity if {@link num} is negative, else {@link num}.
 */
function infinity_if_negative(num) {
	if (num < 0) {
		return Infinity;
	}
	return num;
}

/**
 * @param {string} string The string to search.
 * @param {number} search_start_index The index to start searching at.
 * @param {"'" | '"' | '`'} string_start_char The character that started this string.
 * @returns {number} The index of the end of this string expression, or `Infinity` if not found.
 */
function find_string_end(string, search_start_index, string_start_char) {
	let string_to_search;
	if (string_start_char === '`') {
		string_to_search = string;
	} else {
		// we could slice at the search start index, but this way the index remains valid
		string_to_search = string.slice(
			0,
			infinity_if_negative(string.indexOf('\n', search_start_index))
		);
	}

	return find_unescaped_char(string_to_search, search_start_index, string_start_char);
}

/**
 * @param {string} string The string to search.
 * @param {number} search_start_index The index to start searching at.
 * @returns {number} The index of the end of this regex expression, or `Infinity` if not found.
 */
function find_regex_end(string, search_start_index) {
	return find_unescaped_char(string, search_start_index, '/');
}

/**
 *
 * @param {string} string The string to search.
 * @param {number} search_start_index The index to begin the search at.
 * @param {string} char The character to search for.
 * @returns {number} The index of the first unescaped instance of {@link char}, or `Infinity` if not found.
 */
function find_unescaped_char(string, search_start_index, char) {
	let i = search_start_index;
	while (true) {
		const found_index = string.indexOf(char, i);
		if (found_index === -1) {
			return Infinity;
		}
		if (count_leading_backslashes(string, found_index - 1) % 2 === 0) {
			return found_index;
// ... (154 more lines)