acorn.js — svelte Source File

Source Code

/** @import { Comment, Program } from 'estree' */
/** @import { AST } from '#compiler' */
import * as acorn from 'acorn';
import { walk } from 'zimmerframe';
import { tsPlugin } from '@sveltejs/acorn-typescript';

const ParserWithTS = acorn.Parser.extend(tsPlugin());

/**
 * @typedef {Comment & {
 *   start: number;
 *   end: number;
 * }} CommentWithLocation
 */

/**
 * @param {string} source
 * @param {AST.JSComment[]} comments
 * @param {boolean} typescript
 * @param {boolean} [is_script]
 */
export function parse(source, comments, typescript, is_script) {
	const parser = typescript ? ParserWithTS : acorn.Parser;

	const { onComment, add_comments } = get_comment_handlers(
		source,
		/** @type {CommentWithLocation[]} */ (comments)
	);

	// @ts-ignore
	const parse_statement = parser.prototype.parseStatement;

	// If we're dealing with a <script> then it might contain an export
	// for something that doesn't exist directly inside but is inside the
	// component instead, so we need to ensure that Acorn doesn't throw
	// an error in these cases
	if (is_script) {
		// @ts-ignore
		parser.prototype.parseStatement = function (...args) {
			const v = parse_statement.call(this, ...args);
			// @ts-ignore
			this.undefinedExports = {};
			return v;
		};
	}

	let ast;

	try {
		ast = parser.parse(source, {
			onComment,
			sourceType: 'module',
			ecmaVersion: 16,
			locations: true
		});
	} finally {
		if (is_script) {
			// @ts-ignore
			parser.prototype.parseStatement = parse_statement;
		}
// ... (139 more lines)