element() — svelte Function Reference

Source Code

packages/svelte/src/compiler/phases/1-parse/state/element.js lines 54–422

export default function element(parser) {
	const start = parser.index++;

	let parent = parser.current();

	if (parser.eat('!--')) {
		const data = parser.read_until(regex_closing_comment);
		parser.eat('-->', true);

		parser.append({
			type: 'Comment',
			start,
			end: parser.index,
			data
		});

		return;
	}

	if (parser.eat('/')) {
		const name = parser.read_until(regex_whitespace_or_slash_or_closing_tag);

		parser.allow_whitespace();
		parser.eat('>', true);

		if (is_void(name)) {
			e.void_element_invalid_content(start);
		}

		// close any elements that don't have their own closing tags, e.g. <div><p></div>
		while (/** @type {AST.RegularElement} */ (parent).name !== name) {
			if (parser.loose) {
				// If the previous element did interpret the next opening tag as an attribute, backtrack
				if (is_element_node(parent)) {
					const last = parent.attributes.at(-1);
					if (last?.type === 'Attribute' && last.name === `<${name}`) {
						parser.index = last.start;
						parent.attributes.pop();
						break;
					}
				}
			}

			if (parent.type === 'RegularElement') {
				if (!parser.last_auto_closed_tag || parser.last_auto_closed_tag.tag !== name) {
					const end = parent.fragment.nodes[0]?.start ?? start;
					w.element_implicitly_closed(
						{ start: parent.start, end },
						`</${name}>`,
						`</${parent.name}>`
					);
				}
			} else if (!parser.loose) {
				if (parser.last_auto_closed_tag && parser.last_auto_closed_tag.tag === name) {
					e.element_invalid_closing_tag_autoclosed(start, name, parser.last_auto_closed_tag.reason);
				} else {
					e.element_invalid_closing_tag(start, name);
				}
			}

			parent.end = start;
			parser.pop();

			parent = parser.current();
		}

		parent.end = parser.index;
		parser.pop();

		if (parser.last_auto_closed_tag && parser.stack.length < parser.last_auto_closed_tag.depth) {
			parser.last_auto_closed_tag = undefined;
		}

		return;
	}

	const tag = read_tag(parser, regex_whitespace_or_slash_or_closing_tag);

	if (tag.name.startsWith('svelte:') && !meta_tags.has(tag.name)) {
		const bounds = { start: start + 1, end: start + 1 + tag.name.length };
		e.svelte_meta_invalid_tag(bounds, list(Array.from(meta_tags.keys())));