All files / src/compiler/phases/3-transform/client/visitors javascript-legacy.js

95.12% Statements 195/205
92.45% Branches 49/53
100% Functions 4/4
95.02% Lines 191/201

Press n or j to go to the next uncovered block, b, p or k for the previous block.

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 2022x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 382x 382x 380x 380x 2x 2x 2x 2x 2x 2x 8x 8x 8x 8x 8x 8x 2x 2x 2x 2x 2x 2x 2x 2394x 2394x 2394x 2394x 2734x 2734x 2734x 2734x 2734x 2734x 2734x 436x 436x                     436x 436x 436x 2298x 2734x 1916x 5x 5x 5x 5x 5x 5x 5x 5x 5x 5x 5x 5x 5x 31x 31x 31x 31x 31x 31x 31x 31x 31x 31x 31x 31x 5x 5x 1911x 1911x 1911x 1911x 1911x 1911x 1916x 1916x 31x 1916x 1892x 1892x 1892x 1892x 1892x 1892x 1892x 1892x 937x 1892x 1892x 1892x 1892x 1911x 1911x 1911x 382x 382x 382x 382x 382x 2734x 2734x 2734x 2734x 2394x 2394x 17x 17x 2377x 2377x 2377x 2377x 2377x 2x 2x 139x 2x 2x 2x 137x 137x 137x 137x 137x 137x 137x 137x 139x 137x 137x 137x 137x 137x 139x 118x 118x 137x 137x 137x 137x 137x 139x 213x 173x 173x 173x 173x 173x 173x 213x 108x 108x 173x 173x 173x 137x 137x 137x 137x 137x 137x 137x 139x 139x 139x 139x 139x 139x 139x 2x 2x 1x 1x 1x 1x 1x 1x 1x 1x 2x  
import { is_hoistable_function } from '../../utils.js';
import * as b from '../../../../utils/builders.js';
import { extract_paths } from '../../../../utils/ast.js';
import { get_prop_source, serialize_get_binding } from '../utils.js';
 
/**
 * Creates the output for a state declaration.
 * @param {import('estree').VariableDeclarator} declarator
 * @param {import('../../../scope.js').Scope} scope
 * @param {import('estree').Expression} value
 */
function create_state_declarators(declarator, scope, value) {
	if (declarator.id.type === 'Identifier') {
		return [b.declarator(declarator.id, b.call('$.mutable_source', value))];
	}
 
	const tmp = scope.generate('tmp');
	const paths = extract_paths(declarator.id);
	return [
		b.declarator(b.id(tmp), value),
		...paths.map((path) => {
			const value = path.expression?.(b.id(tmp));
			const binding = scope.get(/** @type {import('estree').Identifier} */ (path.node).name);
			return b.declarator(
				path.node,
				binding?.kind === 'state' ? b.call('$.mutable_source', value) : value
			);
		})
	];
}
 
/** @type {import('../types.js').ComponentVisitors} */
export const javascript_visitors_legacy = {
	VariableDeclaration(node, { state, visit }) {
		/** @type {import('estree').VariableDeclarator[]} */
		const declarations = [];
 
		for (const declarator of node.declarations) {
			const bindings = /** @type {import('#compiler').Binding[]} */ (
				state.scope.get_bindings(declarator)
			);
			const has_state = bindings.some((binding) => binding.kind === 'state');
			const has_props = bindings.some((binding) => binding.kind === 'bindable_prop');
 
			if (!has_state && !has_props) {
				const init = declarator.init;
				if (init != null && is_hoistable_function(init)) {
					const hoistable_function = visit(init);
					state.hoisted.push(
						b.declaration(
							'const',
							declarator.id,
							/** @type {import('estree').Expression} */ (hoistable_function)
						)
					);
					continue;
				}
				declarations.push(/** @type {import('estree').VariableDeclarator} */ (visit(declarator)));
				continue;
			}
 
			if (has_props) {
				if (declarator.id.type !== 'Identifier') {
					// Turn export let into props. It's really really weird because export let { x: foo, z: [bar]} = ..
					// means that foo and bar are the props (i.e. the leafs are the prop names), not x and z.
					const tmp = state.scope.generate('tmp');
					const paths = extract_paths(declarator.id);
					declarations.push(
						b.declarator(
							b.id(tmp),
							/** @type {import('estree').Expression} */ (
								visit(/** @type {import('estree').Expression} */ (declarator.init))
							)
						)
					);
					for (const path of paths) {
						const name = /** @type {import('estree').Identifier} */ (path.node).name;
						const binding = /** @type {import('#compiler').Binding} */ (state.scope.get(name));
						const value = path.expression?.(b.id(tmp));
						declarations.push(
							b.declarator(
								path.node,
								binding.kind === 'bindable_prop'
									? get_prop_source(binding, state, binding.prop_alias ?? name, value)
									: value
							)
						);
					}
					continue;
				}
 
				const binding = /** @type {import('#compiler').Binding} */ (
					state.scope.get(declarator.id.name)
				);
 
				if (
					state.analysis.accessors ||
					(state.analysis.immutable ? binding.reassigned : binding.mutated) ||
					declarator.init
				) {
					declarations.push(
						b.declarator(
							declarator.id,
							get_prop_source(
								binding,
								state,
								binding.prop_alias ?? declarator.id.name,
								declarator.init &&
									/** @type {import('estree').Expression} */ (visit(declarator.init))
							)
						)
					);
				}
 
				continue;
			}
 
			declarations.push(
				...create_state_declarators(
					declarator,
					state.scope,
					/** @type {import('estree').Expression} */ (declarator.init && visit(declarator.init))
				)
			);
		}
 
		if (declarations.length === 0) {
			return b.empty;
		}
 
		return {
			...node,
			declarations
		};
	},
	LabeledStatement(node, context) {
		if (context.path.length > 1 || node.label.name !== '$') {
			context.next();
			return;
		}
 
		const state = context.state;
		// To recreate Svelte 4 behaviour, we track the dependencies
		// the compiler can 'see', but we untrack the effect itself
		const reactive_stmt = /** @type {import('#compiler').ReactiveStatement} */ (
			state.analysis.reactive_statements.get(node)
		);
 
		if (!reactive_stmt) return; // not the instance context
 
		const { dependencies } = reactive_stmt;
 
		let serialized_body = /** @type {import('estree').Statement} */ (context.visit(node.body));
 
		if (serialized_body.type !== 'BlockStatement') {
			serialized_body = b.block([serialized_body]);
		}
 
		const body = serialized_body.body;
 
		/** @type {import('estree').Expression[]} */
		const sequence = [];
		for (const binding of dependencies) {
			if (binding.kind === 'normal') continue;
 
			const name = binding.node.name;
			let serialized = serialize_get_binding(b.id(name), state);
 
			// If the binding is a prop, we need to deep read it because it could be fine-grained $state
			// from a runes-component, where mutations don't trigger an update on the prop as a whole.
			if (name === '$$props' || name === '$$restProps' || binding.kind === 'bindable_prop') {
				serialized = b.call('$.deep_read_state', serialized);
			}
 
			sequence.push(serialized);
		}
 
		// these statements will be topologically ordered later
		state.legacy_reactive_statements.set(
			node,
			b.stmt(
				b.call(
					'$.legacy_pre_effect',
					sequence.length > 0 ? b.thunk(b.sequence(sequence)) : b.thunk(b.block([])),
					b.thunk(b.block(body))
				)
			)
		);
 
		return b.empty;
	},
	BreakStatement(node, context) {
		if (!node.label || node.label.name !== '$') return;
 
		const in_reactive_statement =
			context.path[1].type === 'LabeledStatement' && context.path[1].label.name === '$';
		if (in_reactive_statement) {
			return b.return();
		}
	}
};