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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 | 2x 2x 2x 2x 2x 2x 2x 2x 2x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 45960x 24032x 2x 2x 24030x 24030x 24032x 24032x 24032x 24032x 6x 24032x 1x 1x 24029x 24032x 22150x 1x 1x 22149x 22150x 1728x 1728x 22150x 22300x 24032x 2x 2x 2x 22298x 22298x 22298x 22298x 22298x 22298x 22298x 22298x 22298x 22298x 22298x 22298x 22298x 22298x 22298x 22298x 22298x 22298x 22298x 22298x 22298x 22298x 45960x 45960x 32086x 32086x 45960x 45960x 45960x 45960x 45960x 45960x 15895x 2158x 2158x 13737x 13737x 13737x 13737x 13737x 13737x 15895x 15895x 15895x 13737x 15895x 12121x 12121x 13737x 13737x 13737x 13737x 13737x 45960x 45960x 45960x 45960x 45960x 45960x 391255x 391255x 45960x 45960x 45960x 45960x 45960x 45960x 5637x 5637x 5637x 5637x 45960x 45960x 45960x 45960x 45960x 45960x 1736x 1736x 45960x 45960x 45960x 45960x 45960x 45960x 90881x 90881x 90881x 90881x 90881x 90881x 90881x 90881x 90881x 31234x 90881x 57156x 59647x 2491x 2491x 2491x 2491x 90881x 45960x 2x 2x 4643x 4643x 4643x 4643x 4643x 4643x 4643x 5110x 5110x 5110x 5110x 5110x 2734x 2734x 5110x 5110x 5110x 5110x 5110x 4643x 2x 2x 2x 2x 2x 2x 2x 2x 13874x 13874x 13874x 13874x 13874x 13874x 13874x 13874x 13874x 13874x 13874x 13874x 13874x 13874x 13874x 13874x 13874x 13874x 13874x 13874x 13874x 13874x 13874x 13874x 13874x 13874x 13874x 13874x 13874x 13874x 3197x 1387x 1393x 1393x 1387x 3197x 13874x 13874x 13874x 13874x 13874x 2362x 2362x 2362x 2362x 13874x 13874x 13874x 13874x 13874x 13874x 8872x 8872x 8872x 13874x 13874x 13874x 13874x 13874x 13874x 13874x 10002x 10002x 10002x 10002x 7768x 212x 212x 212x 212x 212x 212x 212x 212x 212x 51x 63x 63x 63x 212x 161x 161x 161x 161x 161x 161x 161x 161x 161x 161x 7768x 197x 197x 7768x 10002x 10002x 10002x 13874x 13874x 13874x 13874x 13874x 393x 393x 393x 89x 89x 13874x 13874x 13874x 13874x 13874x 39996x 39996x 32209x 32209x 13874x 13874x 13874x 295x 295x 289x 289x 289x 289x 289x 289x 295x 220x 295x 189x 183x 179x 179x 183x 189x 289x 289x 13874x 13874x 13874x 13874x 13874x 13874x 13874x 13874x 1130x 1130x 1130x 1237x 1237x 1130x 1130x 1130x 1130x 1130x 1130x 17x 17x 1130x 1130x 1671x 1671x 480x 480x 480x 1671x 180x 180x 180x 1671x 1491x 100x 100x 100x 1491x 1391x 1391x 1491x 1491x 1491x 1671x 13874x 13874x 13874x 13874x 2023x 2023x 13874x 13874x 13874x 322x 322x 322x 322x 322x 322x 322x 13874x 13874x 13874x 1659x 1736x 1736x 13874x 13874x 13874x 280x 280x 280x 280x 280x 280x 280x 13874x 13874x 13874x 980x 980x 980x 980x 980x 980x 980x 13874x 13874x 13874x 1937x 1937x 1937x 1937x 1937x 13874x 13874x 13874x 13874x 13874x 13874x 13874x 13874x 13874x 78x 78x 13874x 13874x 13874x 6642x 6642x 7324x 7324x 7324x 7324x 7324x 7324x 7802x 7802x 7802x 7802x 7802x 7802x 7802x 7802x 7320x 6638x 6638x 13874x 13874x 13874x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 13874x 13874x 13874x 926x 926x 926x 926x 926x 926x 882x 882x 878x 878x 882x 926x 926x 926x 926x 926x 926x 926x 926x 1036x 1036x 1036x 1036x 1036x 1036x 1956x 15x 15x 1036x 1036x 56x 56x 56x 56x 56x 1036x 1036x 1036x 1036x 926x 87x 87x 926x 926x 926x 926x 109x 109x 109x 109x 109x 926x 926x 926x 926x 3221x 3221x 926x 924x 924x 924x 924x 924x 926x 1359x 81x 81x 1359x 924x 924x 924x 926x 926x 926x 926x 926x 926x 926x 926x 926x 13874x 13874x 13874x 171x 171x 171x 90x 90x 171x 171x 143x 143x 131x 131x 131x 131x 131x 183x 183x 183x 131x 143x 171x 171x 99x 99x 93x 93x 93x 93x 93x 149x 149x 149x 93x 99x 13874x 13874x 13874x 84x 84x 84x 84x 84x 66x 66x 84x 84x 84x 84x 84x 84x 44x 44x 44x 44x 84x 84x 13874x 13874x 13874x 14991x 14991x 14991x 13874x 13874x 13874x 896x 896x 896x 896x 896x 896x 896x 13874x 13874x 13874x 13874x 13874x 13874x 13874x 13874x 13874x 13874x 179x 179x 135x 135x 135x 13869x 13869x 13869x 13874x 32202x 32202x 13869x 13874x 3241x 881x 881x 100x 100x 881x 881x 881x 3239x 2360x 2436x 2436x 2326x 2326x 2326x 2360x 2360x 3241x 13869x 13869x 13869x 13869x 13869x 13869x 2x 2x 2x 2x 2x 2x 2x 26847x 26847x 26847x 26847x 26847x 26847x 26847x 291361x 291361x 291361x 26847x 26847x 2x 2x 2x 2x 2x 2x 2x 2x 14097x 14097x 13498x 13498x 13498x 13498x 13498x 14097x 2912x 2912x 2870x 2870x 2870x 13456x 14097x 32x 32x 32x 13456x 14097x 13305x 13305x 13305x 14097x 14003x 7736x 7736x 12142x 7664x 7664x 7664x | import is_reference from 'is-reference';
import { walk } from 'zimmerframe';
import { is_element_node } from './nodes.js';
import * as b from '../utils/builders.js';
import { error } from '../errors.js';
import { extract_identifiers, extract_identifiers_from_destructuring } from '../utils/ast.js';
import { JsKeywords, Runes } from './constants.js';
export class Scope {
/** @type {ScopeRoot} */
root;
/**
* The immediate parent scope
* @type {Scope | null}
*/
parent;
/**
* Whether or not `var` declarations are contained by this scope
* @type {boolean}
*/
#porous;
/**
* A map of every identifier declared by this scope, and all the
* identifiers that reference it
* @type {Map<string, import('#compiler').Binding>}
*/
declarations = new Map();
/**
* A map of declarators to the bindings they declare
* @type {Map<import('estree').VariableDeclarator | import('#compiler').LetDirective, import('#compiler').Binding[]>}
*/
declarators = new Map();
/**
* A set of all the names referenced with this scope
* — useful for generating unique names
* @type {Map<string, { node: import('estree').Identifier; path: import('#compiler').SvelteNode[] }[]>}
*/
references = new Map();
/**
* The scope depth allows us to determine if a state variable is referenced in its own scope,
* which is usually an error. Block statements do not increase this value
*/
function_depth = 0;
/**
*
* @param {ScopeRoot} root
* @param {Scope | null} parent
* @param {boolean} porous
*/
constructor(root, parent, porous) {
this.root = root;
this.parent = parent;
this.#porous = porous;
this.function_depth = parent ? parent.function_depth + (porous ? 0 : 1) : 0;
}
/**
* @param {import('estree').Identifier} node
* @param {import('#compiler').Binding['kind']} kind
* @param {import('#compiler').DeclarationKind} declaration_kind
* @param {null | import('estree').Expression | import('estree').FunctionDeclaration | import('estree').ClassDeclaration | import('estree').ImportDeclaration | import('../types/template.js').EachBlock} initial
* @returns {import('#compiler').Binding}
*/
declare(node, kind, declaration_kind, initial = null) {
if (node.name === '$') {
error(node, 'invalid-dollar-binding');
}
if (
node.name.startsWith('$') &&
declaration_kind !== 'synthetic' &&
declaration_kind !== 'param' &&
declaration_kind !== 'rest_param' &&
this.function_depth <= 1
) {
error(node, 'invalid-dollar-prefix');
}
if (this.parent) {
if (declaration_kind === 'var' && this.#porous) {
return this.parent.declare(node, kind, declaration_kind);
}
if (declaration_kind === 'import') {
return this.parent.declare(node, kind, declaration_kind, initial);
}
}
if (this.declarations.has(node.name)) {
// This also errors on var/function types, but that's arguably a good thing
error(node, 'duplicate-declaration', node.name);
}
/** @type {import('#compiler').Binding} */
const binding = {
node,
references: [],
legacy_dependencies: [],
initial,
mutated: false,
scope: this,
kind,
declaration_kind,
is_called: false,
prop_alias: null,
expression: null,
mutation: null,
reassigned: false,
metadata: null
};
this.declarations.set(node.name, binding);
this.root.conflicts.add(node.name);
return binding;
}
child(porous = false) {
return new Scope(this.root, this, porous);
}
/**
* @param {string} preferred_name
* @returns {string}
*/
generate(preferred_name) {
if (this.#porous) {
return /** @type {Scope} */ (this.parent).generate(preferred_name);
}
preferred_name = preferred_name.replace(/[^a-zA-Z0-9_$]/g, '_').replace(/^[0-9]/, '_');
let name = preferred_name;
let n = 1;
while (
this.references.has(name) ||
this.declarations.has(name) ||
this.root.conflicts.has(name) ||
JsKeywords.includes(name)
) {
name = `${preferred_name}_${n++}`;
}
this.references.set(name, []);
this.root.conflicts.add(name);
return name;
}
/**
* @param {string} name
* @returns {import('#compiler').Binding | null}
*/
get(name) {
return this.declarations.get(name) ?? this.parent?.get(name) ?? null;
}
/**
* @param {import('estree').VariableDeclarator | import('#compiler').LetDirective} node
* @returns {import('#compiler').Binding[]}
*/
get_bindings(node) {
const bindings = this.declarators.get(node);
if (!bindings) {
error(node, 'INTERNAL', 'No binding found for declarator');
}
return bindings;
}
/**
* @param {string} name
* @returns {Scope | null}
*/
owner(name) {
return this.declarations.has(name) ? this : this.parent && this.parent.owner(name);
}
/**
* @param {import('estree').Identifier} node
* @param {import('#compiler').SvelteNode[]} path
*/
reference(node, path) {
path = [...path]; // ensure that mutations to path afterwards don't affect this reference
let references = this.references.get(node.name);
if (!references) this.references.set(node.name, (references = []));
references.push({ node, path });
const binding = this.declarations.get(node.name);
if (binding) {
binding.references.push({ node, path });
} else if (this.parent) {
this.parent.reference(node, path);
} else {
// no binding was found, and this is the top level scope,
// which means this is a global
this.root.conflicts.add(node.name);
}
}
}
export class ScopeRoot {
/** @type {Set<string>} */
conflicts = new Set();
/**
* @param {string} preferred_name
*/
unique(preferred_name) {
preferred_name = preferred_name.replace(/[^a-zA-Z0-9_$]/g, '_');
let final_name = preferred_name;
let n = 1;
while (this.conflicts.has(final_name)) {
final_name = `${preferred_name}_${n++}`;
}
this.conflicts.add(final_name);
const id = b.id(final_name);
return id;
}
}
/**
* @param {import('#compiler').SvelteNode} ast
* @param {ScopeRoot} root
* @param {boolean} allow_reactive_declarations
* @param {Scope | null} parent
*/
export function create_scopes(ast, root, allow_reactive_declarations, parent) {
/** @typedef {{ scope: Scope }} State */
/**
* A map of node->associated scope. A node appearing in this map does not necessarily mean that it created a scope
* @type {Map<import('#compiler').SvelteNode, Scope>}
*/
const scopes = new Map();
const scope = new Scope(root, parent, false);
scopes.set(ast, scope);
/** @type {State} */
const state = { scope };
/** @type {[Scope, { node: import('estree').Identifier; path: import('#compiler').SvelteNode[] }][]} */
const references = [];
/** @type {[Scope, import('estree').Pattern | import('estree').MemberExpression][]} */
const updates = [];
/**
* An array of reactive declarations, i.e. the `a` in `$: a = b * 2`
* @type {import('estree').Identifier[]}
*/
const possible_implicit_declarations = [];
/**
* @param {Scope} scope
* @param {import('estree').Pattern[]} params
*/
function add_params(scope, params) {
for (const param of params) {
for (const node of extract_identifiers(param)) {
scope.declare(node, 'normal', param.type === 'RestElement' ? 'rest_param' : 'param');
}
}
}
/**
* @type {import('zimmerframe').Visitor<import('estree').Node, State, import('#compiler').SvelteNode>}
*/
const create_block_scope = (node, { state, next }) => {
const scope = state.scope.child(true);
scopes.set(node, scope);
next({ scope });
};
/**
* @type {import('zimmerframe').Visitor<import('#compiler').ElementLike, State, import('#compiler').SvelteNode>}
*/
const SvelteFragment = (node, { state, next }) => {
const [scope] = analyze_let_directives(node, state.scope);
scopes.set(node, scope);
next({ scope });
};
/**
* @param {import('#compiler').ElementLike} node
* @param {Scope} parent
*/
function analyze_let_directives(node, parent) {
const scope = parent.child();
let is_default_slot = true;
for (const attribute of node.attributes) {
if (attribute.type === 'LetDirective') {
/** @type {import('#compiler').Binding[]} */
const bindings = [];
scope.declarators.set(attribute, bindings);
// attach the scope to the directive itself, as well as the
// contents to which it applies
scopes.set(attribute, scope);
if (attribute.expression) {
for (const id of extract_identifiers_from_destructuring(attribute.expression)) {
const binding = scope.declare(id, 'derived', 'const');
bindings.push(binding);
}
} else {
/** @type {import('estree').Identifier} */
const id = {
name: attribute.name,
type: 'Identifier',
start: attribute.start,
end: attribute.end
};
const binding = scope.declare(id, 'derived', 'const');
bindings.push(binding);
}
} else if (attribute.type === 'Attribute' && attribute.name === 'slot') {
is_default_slot = false;
}
}
return /** @type {const} */ ([scope, is_default_slot]);
}
/**
* @type {import('zimmerframe').Visitor<import('#compiler').AnimateDirective | import('#compiler').TransitionDirective | import('#compiler').UseDirective, State, import('#compiler').SvelteNode>}
*/
const SvelteDirective = (node, { state, path, visit }) => {
state.scope.reference(b.id(node.name.split('.')[0]), path);
if (node.expression) {
visit(node.expression);
}
};
walk(ast, state, {
// references
Identifier(node, { path, state }) {
const parent = path.at(-1);
if (parent && is_reference(node, /** @type {import('estree').Node} */ (parent))) {
references.push([state.scope, { node, path: path.slice() }]);
}
},
LabeledStatement(node, { path, next }) {
if (path.length > 1 || !allow_reactive_declarations) return next();
if (node.label.name !== '$') return next();
// create a scope for the $: block
const scope = state.scope.child();
scopes.set(node, scope);
if (
node.body.type === 'ExpressionStatement' &&
node.body.expression.type === 'AssignmentExpression'
) {
for (const id of extract_identifiers(node.body.expression.left)) {
if (!id.name.startsWith('$')) {
possible_implicit_declarations.push(id);
}
}
}
next({ scope });
},
SvelteFragment,
SlotElement: SvelteFragment,
SvelteElement: SvelteFragment,
RegularElement: SvelteFragment,
Component(node, { state, visit, path }) {
state.scope.reference(b.id(node.name), path);
for (const attribute of node.attributes) {
visit(attribute);
}
// let:x is super weird:
// - for the default slot, its scope only applies to children that are not slots themselves
// - for named slots, its scope applies to the component itself, too
const [scope, is_default_slot] = analyze_let_directives(node, state.scope);
if (!is_default_slot) {
scopes.set(node, scope);
}
for (const child of node.fragment.nodes) {
if (
is_element_node(child) &&
child.attributes.some(
(attribute) => attribute.type === 'Attribute' && attribute.name === 'slot'
)
) {
// <div slot="..."> inherits the scope above the component unless the component is a named slot itself, because slots are hella weird
scopes.set(child, is_default_slot ? state.scope : scope);
visit(child, { scope: is_default_slot ? state.scope : scope });
} else {
if (child.type === 'ExpressionTag') {
// expression tag is a special case — we don't visit it directly, but via process_children,
// so we need to set the scope on the expression rather than the tag itself
scopes.set(child.expression, scope);
} else {
scopes.set(child, scope);
}
visit(child, { scope });
}
}
},
// updates
AssignmentExpression(node, { state, next }) {
updates.push([state.scope, node.left]);
next();
},
UpdateExpression(node, { state, next }) {
updates.push([
state.scope,
/** @type {import('estree').Identifier | import('estree').MemberExpression} */ (
node.argument
)
]);
next();
},
ImportDeclaration(node, { state }) {
for (const specifier of node.specifiers) {
state.scope.declare(specifier.local, 'normal', 'import', node);
}
},
FunctionExpression(node, { state, next }) {
const scope = state.scope.child();
scopes.set(node, scope);
if (node.id) scope.declare(node.id, 'normal', 'function');
add_params(scope, node.params);
next({ scope });
},
FunctionDeclaration(node, { state, next }) {
if (node.id) state.scope.declare(node.id, 'normal', 'function', node);
const scope = state.scope.child();
scopes.set(node, scope);
add_params(scope, node.params);
next({ scope });
},
ArrowFunctionExpression(node, { state, next }) {
const scope = state.scope.child();
scopes.set(node, scope);
add_params(scope, node.params);
next({ scope });
},
ForStatement: create_block_scope,
ForInStatement: create_block_scope,
ForOfStatement: create_block_scope,
BlockStatement: create_block_scope,
SwitchStatement: create_block_scope,
ClassDeclaration(node, { state, next }) {
if (node.id) state.scope.declare(node.id, 'normal', 'const', node);
next();
},
VariableDeclaration(node, { state, path, next }) {
const is_parent_const_tag = path.at(-1)?.type === 'ConstTag';
for (const declarator of node.declarations) {
/** @type {import('#compiler').Binding[]} */
const bindings = [];
state.scope.declarators.set(declarator, bindings);
for (const id of extract_identifiers(declarator.id)) {
const binding = state.scope.declare(
id,
is_parent_const_tag ? 'derived' : 'normal',
node.kind,
declarator.init
);
bindings.push(binding);
}
}
next();
},
CatchClause(node, { state, next }) {
if (node.param) {
const scope = state.scope.child(true);
scopes.set(node, scope);
for (const id of extract_identifiers(node.param)) {
scope.declare(id, 'normal', 'let');
}
next({ scope });
} else {
next();
}
},
EachBlock(node, { state, visit }) {
// Array part is still from the scope above
/** @type {Set<import('estree').Identifier>} */
const references_within = new Set();
const idx = references.length;
visit(node.expression);
for (let i = idx; i < references.length; i++) {
const [scope, { node: id }] = references[i];
if (scope === state.scope) {
references_within.add(id);
}
}
scopes.set(node.expression, state.scope);
// context and children are a new scope
const scope = state.scope.child();
scopes.set(node, scope);
// declarations
for (const id of extract_identifiers(node.context)) {
const binding = scope.declare(id, 'each', 'const');
let inside_rest = false;
let is_rest_id = false;
walk(node.context, null, {
Identifier(node) {
if (inside_rest && node === id) {
is_rest_id = true;
}
},
RestElement(_, { next }) {
const prev = inside_rest;
inside_rest = true;
next();
inside_rest = prev;
}
});
binding.metadata = { inside_rest: is_rest_id };
}
if (node.context.type !== 'Identifier') {
scope.declare(b.id('$$item'), 'derived', 'synthetic');
}
// Visit to pick up references from default initializers
visit(node.context, { scope });
if (node.index) {
const is_keyed =
node.key &&
(node.key.type !== 'Identifier' || !node.index || node.key.name !== node.index);
scope.declare(b.id(node.index), is_keyed ? 'derived' : 'normal', 'const', node);
}
if (node.key) visit(node.key, { scope });
// children
for (const child of node.body.nodes) {
visit(child, { scope });
}
if (node.fallback) visit(node.fallback, { scope });
// Check if inner scope shadows something from outer scope.
// This is necessary because we need access to the array expression of the each block
// in the inner scope if bindings are used, in order to invalidate the array.
let needs_array_deduplication = false;
for (const [name] of scope.declarations) {
if (state.scope.get(name) !== null) {
needs_array_deduplication = true;
}
}
node.metadata = {
contains_group_binding: false,
array_name: needs_array_deduplication ? state.scope.root.unique('$$array') : null,
index: scope.root.unique('$$index'),
item: node.context.type === 'Identifier' ? node.context : b.id('$$item'),
declarations: scope.declarations,
references: [...references_within]
.map((id) => /** @type {import('#compiler').Binding} */ (state.scope.get(id.name)))
.filter(Boolean),
is_controlled: false
};
},
AwaitBlock(node, context) {
context.visit(node.expression);
if (node.pending) {
context.visit(node.pending);
}
if (node.then) {
context.visit(node.then);
if (node.value) {
const then_scope = /** @type {Scope} */ (scopes.get(node.then));
const value_scope = context.state.scope.child();
scopes.set(node.value, value_scope);
context.visit(node.value, { scope: value_scope });
for (const id of extract_identifiers(node.value)) {
then_scope.declare(id, 'normal', 'const');
value_scope.declare(id, 'normal', 'const');
}
}
}
if (node.catch) {
context.visit(node.catch);
if (node.error) {
const catch_scope = /** @type {Scope} */ (scopes.get(node.catch));
const error_scope = context.state.scope.child();
scopes.set(node.error, error_scope);
context.visit(node.error, { scope: error_scope });
for (const id of extract_identifiers(node.error)) {
catch_scope.declare(id, 'normal', 'const');
error_scope.declare(id, 'normal', 'const');
}
}
}
},
SnippetBlock(node, context) {
const state = context.state;
// Special-case for root-level snippets: they become part of the instance scope
const is_top_level = !context.path.at(-2);
let scope = state.scope;
if (is_top_level) {
scope = /** @type {Scope} */ (parent);
}
scope.declare(node.expression, 'normal', 'function', node.expression);
const child_scope = state.scope.child();
scopes.set(node, child_scope);
for (const param of node.parameters) {
for (const id of extract_identifiers(param)) {
child_scope.declare(id, 'snippet', 'let');
}
}
context.next({ scope: child_scope });
},
Fragment: (node, context) => {
const scope = context.state.scope.child(node.transparent);
scopes.set(node, scope);
context.next({ scope });
},
BindDirective(node, context) {
updates.push([
context.state.scope,
/** @type {import('estree').Identifier | import('estree').MemberExpression} */ (
node.expression
)
]);
context.next();
},
TransitionDirective: SvelteDirective,
AnimateDirective: SvelteDirective,
UseDirective: SvelteDirective
// TODO others
});
for (const id of possible_implicit_declarations) {
const binding = scope.get(id.name);
if (binding) continue; // TODO can also be legacy_reactive if declared outside of reactive statement
scope.declare(id, 'legacy_reactive', 'let');
}
// we do this after the fact, so that we don't need to worry
// about encountering references before their declarations
for (const [scope, { node, path }] of references) {
scope.reference(node, path);
}
for (const [scope, node] of updates) {
if (node.type === 'MemberExpression') {
let object = node.object;
while (object.type === 'MemberExpression') {
object = object.object;
}
const binding = scope.get(/** @type {import('estree').Identifier} */ (object).name);
if (binding) binding.mutated = true;
} else {
extract_identifiers(node).forEach((identifier) => {
const binding = scope.get(identifier.name);
if (binding) {
binding.mutated = true;
binding.reassigned = true;
}
});
}
}
return {
scope,
scopes
};
}
/**
* @template {{ scope: Scope }} State
* @param {Map<import('#compiler').SvelteNode, Scope>} scopes
* @returns {import('zimmerframe').Visitors<import('#compiler').SvelteNode, State>}
*/
export function set_scope(scopes) {
return {
/**
*
* @param {import('#compiler').SvelteNode} node
* @param {import('zimmerframe').Context<import('#compiler').SvelteNode, State>} context
*/
_(node, { next, state }) {
const scope = scopes.get(node);
next(scope !== undefined && scope !== state.scope ? { ...state, scope } : state);
}
};
}
/**
* Returns the name of the rune if the given expression is a `CallExpression` using a rune.
* @param {import('estree').Node | import('../types/template.js').EachBlock | null | undefined} node
* @param {Scope} scope
* @returns {Runes[number] | null}
*/
export function get_rune(node, scope) {
if (!node) return null;
if (node.type !== 'CallExpression') return null;
let n = node.callee;
let joined = '';
while (n.type === 'MemberExpression') {
if (n.computed) return null;
if (n.property.type !== 'Identifier') return null;
joined = '.' + n.property.name + joined;
n = n.object;
}
if (n.type === 'CallExpression' && n.callee.type === 'Identifier') {
joined = '()' + joined;
n = n.callee;
}
if (n.type !== 'Identifier') return null;
joined = n.name + joined;
if (joined === '$derived.call') error(node, 'invalid-derived-call');
if (!Runes.includes(/** @type {any} */ (joined))) return null;
const binding = scope.get(n.name);
if (binding !== null) return null; // rune name, but references a variable or store
return /** @type {typeof Runes[number] | null} */ (joined);
}
|