svelte/src/compiler/compile/render_dom/wrappers/SlotTemplate.ts

import Wrapper from './shared/Wrapper.js';
import FragmentWrapper from './Fragment.js';
import create_debugging_comment from './shared/create_debugging_comment.js';
import { get_slot_definition } from './shared/get_slot_definition.js';
import { b, x } from 'code-red';
import { sanitize } from '../../../utils/names.js';
import { extract_names } from 'periscopic';
import { add_const_tags, add_const_tags_context } from './shared/add_const_tags.js';

/** @extends Wrapper<import('../../nodes/SlotTemplate.js').default> */
export default class SlotTemplateWrapper extends Wrapper {
	/** @type {import('./Fragment.js').default} */
	fragment;

	/** @type {import('../Block.js').default} */
	block;

	/**
	 * @param {import('../Renderer.js').default} renderer
	 * @param {import('../Block.js').default} block
	 * @param {import('./shared/Wrapper.js').default} parent
	 * @param {import('../../nodes/SlotTemplate.js').default} node
	 * @param {boolean} strip_whitespace
	 * @param {import('./shared/Wrapper.js').default} next_sibling
	 */
	constructor(renderer, block, parent, node, strip_whitespace, next_sibling) {
		super(renderer, block, parent, node);
		const { scope, lets, const_tags, slot_template_name } = this.node;
		lets.forEach((l) => {
			extract_names(l.value || l.name).forEach((name) => {
				renderer.add_to_context(name, true);
			});
		});
		add_const_tags_context(renderer, const_tags);
		this.block = block.child({
			comment: create_debugging_comment(this.node, this.renderer.component),
			name: this.renderer.component.get_unique_name(`create_${sanitize(slot_template_name)}_slot`),
			type: 'slot'
		});
		this.renderer.blocks.push(this.block);
		const seen = new Set(lets.map((l) => l.name.name));
		this.parent.node.lets.forEach((l) => {
			if (!seen.has(l.name.name)) lets.push(l);
		});
		/** @type {import('./InlineComponent/index.js').default} */ (this.parent).set_slot(
			slot_template_name,
			get_slot_definition(this.block, scope, lets)
		);
		this.fragment = new FragmentWrapper(
			renderer,
			this.block,
			node.type === 'SlotTemplate' ? node.children : [node],
			this,
			strip_whitespace,
			next_sibling
		);
		this.block.parent.add_dependencies(this.block.dependencies);
	}
	render() {
		this.fragment.render(this.block, null, /** @type {import('estree').Identifier} */ (x`#nodes`));
		if (this.node.const_tags.length > 0) {
			this.render_get_context();
		}
	}
	render_get_context() {
		const get_context = this.block.renderer.component.get_unique_name('get_context');
		this.block.renderer.blocks.push(b`
			function ${get_context}(#ctx) {
				${add_const_tags(this.block, this.node.const_tags, '#ctx')}
			}
		`);
		this.block.chunks.declarations.push(b`${get_context}(#ctx)`);
		if (this.block.has_update_method) {
			this.block.chunks.update.unshift(b`${get_context}(#ctx)`);
		}
	}
}