All files / src/compiler/phases/3-transform/client utils.js

99.33% Statements 752/757
95.31% Branches 244/256
100% Functions 17/17
99.33% Lines 749/754

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 7552x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 1422x 1138x 1138x 1138x 1138x 97x 97x 97x 97x 1138x 1422x 284x 284x 284x 14x 284x 12x 12x 12x 12x 2x 2x 2x 2x 12x 284x 272x 272x 1422x 2x 2x 2x 2x 2x 2x 2x 6021x 6021x 2060x 6021x 6021x 2x 2x 2x 2x 2x 2x 2x 13678x 13678x 13678x 3493x 3493x 3493x 10185x 13678x 8x 8x 8x 10177x 13678x 272x 272x 9905x 13678x 1294x 1294x 8611x 13678x 2984x 2836x 2836x 148x 148x 148x 148x 148x     5627x 13678x 9x 9x 5618x 5618x 13678x 13678x 3680x 13678x 2031x 2031x 3587x 3587x 3587x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 1780x 1780x 1780x 1780x 1780x 1780x 1728x 1780x 52x 52x 52x 52x 52x 52x 52x 52x 52x 52x 52x 52x 99x 99x 99x 99x 99x 99x 99x 52x 52x 2x 2x 2x 50x 50x 50x 50x 50x 52x 52x 52x 52x 52x 52x 52x 52x 52x 52x 52x 52x 52x 52x 21x 52x 29x 29x 52x 1728x 1780x     1728x 1728x 1780x 501x 501x 39x 501x 14x 14x 14x 12x 5x 5x 5x 5x 5x 5x 4x 4x 4x 4x 4x 4x 4x 4x 4x 12x 7x 7x 7x 7x 7x 7x 7x 4x 4x 7x 7x 7x 12x 501x 487x 487x 24x 487x 12x 12x 12x 12x 12x 12x 12x 10x 12x 9x 9x 9x 9x 9x 9x 9x 9x 9x 12x 501x 1708x 1708x 1708x 1780x 27x 27x 1681x 1681x 1681x 1780x 1675x 1780x 66x 66x 1609x 1780x 2x 2x 2x 2x 2x 2x 2x 2x 2x 1607x 1607x 1780x 1780x 1780x 1780x 1780x 1780x 1780x 1780x 1780x 343x 1780x 277x 277x 277x 1330x 1330x 1330x 1330x 1330x 1118x 1118x 653x 653x 653x 1118x 1118x 323x 1118x 42x 795x 753x 753x 667x 667x 667x 667x 667x 275x 667x 667x 667x 753x 3x 3x 3x 3x 3x 3x 3x 3x 3x 83x 83x 18x 83x 18x 18x 18x 18x 2x 18x 18x 18x 83x 65x 65x 753x 753x 30x 753x 723x 723x 753x 1330x 212x 24x 24x 24x 24x 24x 24x 24x 24x 24x 57x 33x 33x 33x 33x 33x 33x 24x 24x 24x 24x 24x 24x 24x 24x 24x 24x   57x 24x 24x 24x 24x 24x 24x 24x 24x 24x 24x 24x 212x 188x 68x 68x 188x 134x 69x 69x 69x 69x 69x 69x 69x 69x 69x 134x 65x 65x 65x 65x 65x 65x 65x 65x 65x 65x 188x 54x 54x 7x 54x 7x 7x 7x 7x 7x 54x 47x 47x 47x 47x 47x 47x 212x 1330x 1330x 1780x 1x 1x 1329x 1329x 1329x 2x 2x 2x 2x 2x 2x 2x 169x 169x 18x 18x 18x 18x 18x 18x 18x 169x 169x 2x 2x 2x 2x 2x 2x 1241x 1241x 1241x 1241x 1241x 154x 154x 154x 154x 1241x 1087x 1087x 1241x 1241x 167x 167x 167x 167x 167x 167x 167x 167x 1074x 1074x 1074x 2x 2x 2x 2x 2x 2x 187x 187x 187x 187x 187x 187x 187x 187x 187x 187x 187x 214x 214x 214x 214x 187x 187x 271x 271x 271x 207x 6x 6x 6x 6x 6x 6x 207x 207x 207x 207x 207x 207x 207x 207x 207x 1x 207x 1x 207x 206x 206x 23x 206x 4x 206x 202x 202x 202x 202x 202x 1x 1x 202x 207x 271x 187x 187x 2x 2x 2x 2x 2x 2x 2x 187x 187x 187x 187x 187x 187x 187x 176x 164x 164x 164x 187x 11x 11x 11x 11x 187x 187x 187x 187x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2010x 2010x 2010x 2010x 2010x 2010x 69x 69x 2010x 2010x 61x 61x 2010x 2010x 2010x 92x 92x 92x 2010x 1945x 1945x 2010x 2010x 2010x 2010x 2010x 1005x 1005x 777x 1005x 228x 228x 228x 20x 228x 10x 228x 218x 218x 228x 228x 228x 1005x 2010x 2010x 1991x 1991x 1991x 2010x 2010x 2010x 2x 2x 2x 2x 2x 2x 2x 2x 3152x 3152x 3152x 3152x 3152x 3152x 301x 301x 3152x 3152x 3152x 2x 2x 2x 2x 2x 2x 1446x 1446x 1446x 1446x 1446x 1446x 1446x 1446x 768x 1446x 728x 728x 1446x 88x 88x 88x 88x 88x 88x 88x 88x 88x 21x 88x 21x 21x 88x 697x 697x 2x 2x 2x 2x 2x 2x 2x 2x 2x 905x 732x 732x 173x 173x 2x 2x 2x 2x 2x 2x 2x 112x 77x 77x 35x 35x 35x 35x 35x 35x 35x 35x 35x 35x 35x 35x 35x 35x 97x 89x 89x 89x 89x 35x 35x 35x 2x 2x 2x 2x 2x 2x 2x 387x 387x  
import * as b from '../../../utils/builders.js';
import {
	extract_identifiers,
	extract_paths,
	is_expression_async,
	is_simple_expression,
	object
} from '../../../utils/ast.js';
import {
	PROPS_IS_LAZY_INITIAL,
	PROPS_IS_IMMUTABLE,
	PROPS_IS_RUNES,
	PROPS_IS_UPDATED
} from '../../../../constants.js';
 
/**
 * @template {import('./types').ClientTransformState} State
 * @param {import('estree').AssignmentExpression} node
 * @param {import('zimmerframe').Context<import('#compiler').SvelteNode, State>} context
 * @returns
 */
export function get_assignment_value(node, { state, visit }) {
	if (node.left.type === 'Identifier') {
		const operator = node.operator;
		return operator === '='
			? /** @type {import('estree').Expression} */ (visit(node.right))
			: // turn something like x += 1 into x = x + 1
				b.binary(
					/** @type {import('estree').BinaryOperator} */ (operator.slice(0, -1)),
					serialize_get_binding(node.left, state),
					/** @type {import('estree').Expression} */ (visit(node.right))
				);
	} else if (
		node.left.type === 'MemberExpression' &&
		node.left.object.type === 'ThisExpression' &&
		node.left.property.type === 'PrivateIdentifier' &&
		state.private_state.has(node.left.property.name)
	) {
		const operator = node.operator;
		return operator === '='
			? /** @type {import('estree').Expression} */ (visit(node.right))
			: // turn something like x += 1 into x = x + 1
				b.binary(
					/** @type {import('estree').BinaryOperator} */ (operator.slice(0, -1)),
					/** @type {import('estree').Expression} */ (visit(node.left)),
					/** @type {import('estree').Expression} */ (visit(node.right))
				);
	} else {
		return /** @type {import('estree').Expression} */ (visit(node.right));
	}
}
 
/**
 * @param {import('#compiler').Binding} binding
 * @param {import('./types').ClientTransformState} state
 * @returns {boolean}
 */
export function is_state_source(binding, state) {
	return (
		(binding.kind === 'state' || binding.kind === 'frozen_state') &&
		(!state.analysis.immutable || binding.reassigned || state.analysis.accessors)
	);
}
 
/**
 * @param {import('estree').Identifier} node
 * @param {import('./types').ClientTransformState} state
 * @returns {import('estree').Expression}
 */
export function serialize_get_binding(node, state) {
	const binding = state.scope.get(node.name);
 
	if (binding === null || node === binding.node) {
		// No associated binding or the declaration itself which shouldn't be transformed
		return node;
	}
 
	if (binding.node.name === '$$props') {
		// Special case for $$props which only exists in the old world
		return b.id('$$sanitized_props');
	}
 
	if (binding.kind === 'store_sub') {
		return b.call(node);
	}
 
	if (binding.expression) {
		return typeof binding.expression === 'function' ? binding.expression(node) : binding.expression;
	}
 
	if (binding.kind === 'prop' || binding.kind === 'bindable_prop') {
		if (is_prop_source(binding, state)) {
			return b.call(node);
		}
 
		if (binding.prop_alias) {
			const key = b.key(binding.prop_alias);
			return b.member(b.id('$$props'), key, key.type === 'Literal');
		}
		return b.member(b.id('$$props'), node);
	}
 
	if (binding.kind === 'legacy_reactive_import') {
		return b.call('$$_import_' + node.name);
	}
 
	if (
		is_state_source(binding, state) ||
		binding.kind === 'derived' ||
		binding.kind === 'legacy_reactive'
	) {
		return b.call('$.get', node);
	}
 
	return node;
}
 
/**
 * @template {import('./types').ClientTransformState} State
 * @param {import('estree').AssignmentExpression} node
 * @param {import('zimmerframe').Context<import('#compiler').SvelteNode, State>} context
 * @param {() => any} fallback
 * @param {boolean | null} [prefix] - If the assignment is a transformed update expression, set this. Else `null`
 * @param {{skip_proxy_and_freeze?: boolean}} [options]
 * @returns {import('estree').Expression}
 */
export function serialize_set_binding(node, context, fallback, prefix, options) {
	const { state, visit } = context;
 
	const assignee = node.left;
	if (
		assignee.type === 'ArrayPattern' ||
		assignee.type === 'ObjectPattern' ||
		assignee.type === 'RestElement'
	) {
		// Turn assignment into an IIFE, so that `$.set` calls etc don't produce invalid code
		const tmp_id = context.state.scope.generate('tmp');
 
		/** @type {import('estree').AssignmentExpression[]} */
		const original_assignments = [];
 
		/** @type {import('estree').Expression[]} */
		const assignments = [];
 
		const paths = extract_paths(assignee);
 
		for (const path of paths) {
			const value = path.expression?.(b.id(tmp_id));
			const assignment = b.assignment('=', path.node, value);
			original_assignments.push(assignment);
			assignments.push(
				serialize_set_binding(assignment, context, () => assignment, prefix, options)
			);
		}
 
		if (assignments.every((assignment, i) => assignment === original_assignments[i])) {
			// No change to output -> nothing to transform -> we can keep the original assignment
			return fallback();
		}
 
		const rhs_expression = /** @type {import('estree').Expression} */ (visit(node.right));
 
		const iife_is_async =
			is_expression_async(rhs_expression) ||
			assignments.some((assignment) => is_expression_async(assignment));
 
		const iife = b.arrow(
			[],
			b.block([
				b.const(tmp_id, rhs_expression),
				b.stmt(b.sequence(assignments)),
				// return because it could be used in a nested expression where the value is needed.
				// example: { foo: ({ bar } = { bar: 1 })}
				b.return(b.id(tmp_id))
			])
		);
 
		if (iife_is_async) {
			return b.await(b.call(b.async(iife)));
		} else {
			return b.call(iife);
		}
	}
 
	if (assignee.type !== 'Identifier' && assignee.type !== 'MemberExpression') {
		throw new Error(`Unexpected assignment type ${assignee.type}`);
	}
 
	// Handle class private/public state assignment cases
	if (assignee.type === 'MemberExpression') {
		if (
			assignee.object.type === 'ThisExpression' &&
			assignee.property.type === 'PrivateIdentifier'
		) {
			const private_state = context.state.private_state.get(assignee.property.name);
			const value = get_assignment_value(node, context);
			if (private_state !== undefined) {
				if (state.in_constructor) {
					// See if we should wrap value in $.proxy
					if (
						context.state.analysis.runes &&
						!options?.skip_proxy_and_freeze &&
						should_proxy_or_freeze(value, context.state.scope)
					) {
						const assignment = fallback();
						if (assignment.type === 'AssignmentExpression') {
							assignment.right =
								private_state.kind === 'frozen_state'
									? b.call('$.freeze', value)
									: serialize_proxy_reassignment(value, private_state.id, state);
							return assignment;
						}
					}
				} else {
					return b.call(
						'$.set',
						assignee,
						context.state.analysis.runes &&
							!options?.skip_proxy_and_freeze &&
							should_proxy_or_freeze(value, context.state.scope)
							? private_state.kind === 'frozen_state'
								? b.call('$.freeze', value)
								: serialize_proxy_reassignment(value, private_state.id, state)
							: value
					);
				}
			}
		} else if (
			assignee.object.type === 'ThisExpression' &&
			assignee.property.type === 'Identifier' &&
			state.in_constructor
		) {
			const public_state = context.state.public_state.get(assignee.property.name);
			const value = get_assignment_value(node, context);
			// See if we should wrap value in $.proxy
			if (
				context.state.analysis.runes &&
				public_state !== undefined &&
				!options?.skip_proxy_and_freeze &&
				should_proxy_or_freeze(value, context.state.scope)
			) {
				const assignment = fallback();
				if (assignment.type === 'AssignmentExpression') {
					assignment.right =
						public_state.kind === 'frozen_state'
							? b.call('$.freeze', value)
							: serialize_proxy_reassignment(value, public_state.id, state);
					return assignment;
				}
			}
		}
	}
 
	const left = object(assignee);
 
	if (left === null) {
		return fallback();
	}
 
	const binding = state.scope.get(left.name);
 
	if (!binding) return fallback();
 
	if (binding.mutation !== null) {
		return binding.mutation(node, context);
	}
 
	if (binding.kind === 'legacy_reactive_import') {
		return b.call(
			'$$_import_' + binding.node.name,
			b.assignment(
				node.operator,
				/** @type {import('estree').Pattern} */ (visit(node.left)),
				/** @type {import('estree').Expression} */ (visit(node.right))
			)
		);
	}
 
	const is_store = binding.kind === 'store_sub';
	const left_name = is_store ? left.name.slice(1) : left.name;
 
	if (
		binding.kind !== 'state' &&
		binding.kind !== 'frozen_state' &&
		binding.kind !== 'prop' &&
		binding.kind !== 'bindable_prop' &&
		binding.kind !== 'each' &&
		binding.kind !== 'legacy_reactive' &&
		!is_store
	) {
		// TODO error if it's a computed (or rest prop)? or does that already happen elsewhere?
		return fallback();
	}
 
	const value = get_assignment_value(node, context);
 
	const serialize = () => {
		if (left === node.left) {
			const is_initial_proxy =
				binding.initial !== null &&
				should_proxy_or_freeze(
					/**@type {import("estree").Expression}*/ (binding.initial),
					context.state.scope
				);
			if ((binding.kind === 'prop' || binding.kind === 'bindable_prop') && !is_initial_proxy) {
				return b.call(left, value);
			} else if (is_store) {
				return b.call('$.store_set', serialize_get_binding(b.id(left_name), state), value);
			} else {
				let call;
				if (binding.kind === 'state') {
					call = b.call(
						'$.set',
						b.id(left_name),
						context.state.analysis.runes &&
							!options?.skip_proxy_and_freeze &&
							should_proxy_or_freeze(value, context.state.scope)
							? serialize_proxy_reassignment(value, left_name, state)
							: value
					);
				} else if (binding.kind === 'frozen_state') {
					call = b.call(
						'$.set',
						b.id(left_name),
						context.state.analysis.runes &&
							!options?.skip_proxy_and_freeze &&
							should_proxy_or_freeze(value, context.state.scope)
							? b.call('$.freeze', value)
							: value
					);
				} else if (
					(binding.kind === 'prop' || binding.kind === 'bindable_prop') &&
					is_initial_proxy
				) {
					call = b.call(
						left,
						context.state.analysis.runes &&
							!options?.skip_proxy_and_freeze &&
							should_proxy_or_freeze(value, context.state.scope)
							? serialize_proxy_reassignment(value, left_name, state)
							: value
					);
				} else {
					call = b.call('$.set', b.id(left_name), value);
				}
 
				if (state.scope.get(`$${left.name}`)?.kind === 'store_sub') {
					return b.call('$.store_unsub', call, b.literal(`$${left.name}`), b.id('$$stores'));
				} else {
					return call;
				}
			}
		} else {
			if (is_store) {
				// If we are assigning to a store property, we need to ensure we don't
				// capture the read for the store as part of the member expression to
				// keep consistency with how store $ shorthand reads work in Svelte 4.
				/**
				 *
				 * @param {import("estree").Expression | import("estree").Pattern} node
				 * @returns {import("estree").Expression}
				 */
				function visit_node(node) {
					if (node.type === 'MemberExpression') {
						return {
							...node,
							object: visit_node(/** @type {import("estree").Expression} */ (node.object)),
							property: /** @type {import("estree").MemberExpression} */ (visit(node)).property
						};
					}
					if (node.type === 'Identifier') {
						const binding = state.scope.get(node.name);
 
						if (binding !== null && binding.kind === 'store_sub') {
							return b.call(
								'$.untrack',
								b.thunk(/** @type {import('estree').Expression} */ (visit(node)))
							);
						}
					}
					return /** @type {import("estree").Expression} */ (visit(node));
				}
 
				return b.call(
					'$.mutate_store',
					serialize_get_binding(b.id(left_name), state),
					b.assignment(
						node.operator,
						/** @type {import("estree").Pattern}} */ (visit_node(node.left)),
						value
					),
					b.call('$.untrack', b.id('$' + left_name))
				);
			} else if (
				!state.analysis.runes ||
				// this condition can go away once legacy mode is gone; only necessary for interop with legacy parent bindings
				(binding.mutated && binding.kind === 'bindable_prop')
			) {
				if (binding.kind === 'bindable_prop') {
					return b.call(
						left,
						b.assignment(
							node.operator,
							/** @type {import('estree').Pattern} */ (visit(node.left)),
							value
						),
						b.true
					);
				} else {
					return b.call(
						'$.mutate',
						b.id(left_name),
						b.assignment(
							node.operator,
							/** @type {import('estree').Pattern} */ (visit(node.left)),
							value
						)
					);
				}
			} else if (
				node.right.type === 'Literal' &&
				prefix != null &&
				(node.operator === '+=' || node.operator === '-=')
			) {
				return b.update(
					node.operator === '+=' ? '++' : '--',
					/** @type {import('estree').Expression} */ (visit(node.left)),
					prefix
				);
			} else {
				return b.assignment(
					node.operator,
					/** @type {import('estree').Pattern} */ (visit(node.left)),
					/** @type {import('estree').Expression} */ (visit(node.right))
				);
			}
		}
	};
 
	if (value.type === 'BinaryExpression' && /** @type {any} */ (value.operator) === '??') {
		return b.logical('??', serialize_get_binding(b.id(left_name), state), serialize());
	}
 
	return serialize();
}
 
/**
 * @param {import('estree').Expression} value
 * @param {import('estree').PrivateIdentifier | string} proxy_reference
 * @param {import('./types').ClientTransformState} state
 */
export function serialize_proxy_reassignment(value, proxy_reference, state) {
	return state.options.dev
		? b.call(
				'$.proxy',
				value,
				b.null,
				typeof proxy_reference === 'string'
					? b.id(proxy_reference)
					: b.member(b.this, proxy_reference)
			)
		: b.call('$.proxy', value);
}
 
/**
 * @param {import('estree').ArrowFunctionExpression | import('estree').FunctionExpression} node
 * @param {import('./types').ComponentContext} context
 */
export const function_visitor = (node, context) => {
	const metadata = node.metadata;
 
	let state = context.state;
 
	if (node.type === 'FunctionExpression') {
		const parent = /** @type {import('estree').Node} */ (context.path.at(-1));
		const in_constructor = parent.type === 'MethodDefinition' && parent.kind === 'constructor';
 
		state = { ...context.state, in_constructor };
	} else {
		state = { ...context.state, in_constructor: false };
	}
 
	if (metadata?.hoistable === true) {
		const params = serialize_hoistable_params(node, context);
 
		return /** @type {import('estree').FunctionExpression} */ ({
			...node,
			params,
			body: context.visit(node.body, state)
		});
	}
 
	context.next(state);
};
 
/**
 * @param {import('estree').FunctionDeclaration | import('estree').FunctionExpression | import('estree').ArrowFunctionExpression} node
 * @param {import('./types').ComponentContext} context
 * @returns {import('estree').Pattern[]}
 */
function get_hoistable_params(node, context) {
	const scope = context.state.scope;
 
	/** @type {import('estree').Identifier[]} */
	const params = [];
 
	/**
	 * We only want to push if it's not already present to avoid name clashing
	 * @param {import('estree').Identifier} id
	 */
	function push_unique(id) {
		if (!params.find((param) => param.name === id.name)) {
			params.push(id);
		}
	}
 
	for (const [reference] of scope.references) {
		let binding = scope.get(reference);
 
		if (binding !== null && !scope.declarations.has(reference) && binding.initial !== node) {
			if (binding.kind === 'store_sub') {
				// We need both the subscription for getting the value and the store for updating
				push_unique(b.id(binding.node.name));
				binding = /** @type {import('#compiler').Binding} */ (
					scope.get(binding.node.name.slice(1))
				);
			}
 
			if (
				// If it's a destructured derived binding, then we can extract the derived signal reference and use that.
				binding.expression !== null &&
				typeof binding.expression !== 'function' &&
				binding.expression.type === 'MemberExpression' &&
				binding.expression.object.type === 'CallExpression' &&
				binding.expression.object.callee.type === 'Identifier' &&
				binding.expression.object.callee.name === '$.get' &&
				binding.expression.object.arguments[0].type === 'Identifier'
			) {
				push_unique(b.id(binding.expression.object.arguments[0].name));
			} else if (
				// If we are referencing a simple $$props value, then we need to reference the object property instead
				(binding.kind === 'prop' || binding.kind === 'bindable_prop') &&
				!is_prop_source(binding, context.state)
			) {
				push_unique(b.id('$$props'));
			} else {
				// create a copy to remove start/end tags which would mess up source maps
				push_unique(b.id(binding.node.name));
				// rest props are often accessed through the $$props object for optimization reasons,
				// but we can't know if the delegated event handler will use it, so we need to add both as params
				if (binding.kind === 'rest_prop' && context.state.analysis.runes) {
					push_unique(b.id('$$props'));
				}
			}
		}
	}
	return params;
}
 
/**
 * @param {import('estree').FunctionDeclaration | import('estree').FunctionExpression | import('estree').ArrowFunctionExpression} node
 * @param {import('./types').ComponentContext} context
 * @returns {import('estree').Pattern[]}
 */
export function serialize_hoistable_params(node, context) {
	const hoistable_params = get_hoistable_params(node, context);
	node.metadata.hoistable_params = hoistable_params;
 
	/** @type {import('estree').Pattern[]} */
	const params = [];
 
	if (node.params.length === 0) {
		if (hoistable_params.length > 0) {
			// For the event object
			params.push(b.id('_'));
		}
	} else {
		for (const param of node.params) {
			params.push(/** @type {import('estree').Pattern} */ (context.visit(param)));
		}
	}
 
	params.push(...hoistable_params);
	return params;
}
 
/**
 * @param {import('#compiler').Binding} binding
 * @param {import('./types').ComponentClientTransformState} state
 * @param {string} name
 * @param {import('estree').Expression | null} [initial]
 * @returns
 */
export function get_prop_source(binding, state, name, initial) {
	/** @type {import('estree').Expression[]} */
	const args = [b.id('$$props'), b.literal(name)];
 
	let flags = 0;
 
	if (state.analysis.immutable) {
		flags |= PROPS_IS_IMMUTABLE;
	}
 
	if (state.analysis.runes) {
		flags |= PROPS_IS_RUNES;
	}
 
	if (
		state.analysis.accessors ||
		(state.analysis.immutable
			? binding.reassigned || (state.analysis.runes && binding.mutated)
			: binding.mutated)
	) {
		flags |= PROPS_IS_UPDATED;
	}
 
	/** @type {import('estree').Expression | undefined} */
	let arg;
 
	if (initial) {
		// To avoid eagerly evaluating the right-hand-side, we wrap it in a thunk if necessary
		if (is_simple_expression(initial)) {
			arg = initial;
		} else {
			if (
				initial.type === 'CallExpression' &&
				initial.callee.type === 'Identifier' &&
				initial.arguments.length === 0
			) {
				arg = initial.callee;
			} else {
				arg = b.thunk(initial);
			}
 
			flags |= PROPS_IS_LAZY_INITIAL;
		}
	}
 
	if (flags || arg) {
		args.push(b.literal(flags));
		if (arg) args.push(arg);
	}
 
	return b.call('$.prop', ...args);
}
 
/**
 *
 * @param {import('#compiler').Binding} binding
 * @param {import('./types').ClientTransformState} state
 * @returns
 */
export function is_prop_source(binding, state) {
	return (
		(binding.kind === 'prop' || binding.kind === 'bindable_prop') &&
		(!state.analysis.runes ||
			state.analysis.accessors ||
			binding.reassigned ||
			binding.initial ||
			// Until legacy mode is gone, we also need to use the prop source when only mutated is true,
			// because the parent could be a legacy component which needs coarse-grained reactivity
			binding.mutated)
	);
}
 
/**
 * @param {import('estree').Expression} node
 * @param {import("../../scope.js").Scope | null} scope
 */
export function should_proxy_or_freeze(node, scope) {
	if (
		!node ||
		node.type === 'Literal' ||
		node.type === 'TemplateLiteral' ||
		node.type === 'ArrowFunctionExpression' ||
		node.type === 'FunctionExpression' ||
		node.type === 'UnaryExpression' ||
		node.type === 'BinaryExpression' ||
		(node.type === 'Identifier' && node.name === 'undefined')
	) {
		return false;
	}
	if (node.type === 'Identifier' && scope !== null) {
		const binding = scope.get(node.name);
		// Let's see if the reference is something that can be proxied or frozen
		if (
			binding !== null &&
			!binding.reassigned &&
			binding.initial !== null &&
			binding.initial.type !== 'FunctionDeclaration' &&
			binding.initial.type !== 'ClassDeclaration' &&
			binding.initial.type !== 'ImportDeclaration' &&
			binding.initial.type !== 'EachBlock'
		) {
			return should_proxy_or_freeze(binding.initial, null);
		}
	}
	return true;
}
 
/**
 * Port over the location information from the source to the target identifier.
 * but keep the target as-is (i.e. a new id is created).
 * This ensures esrap can generate accurate source maps.
 * @param {import('estree').Identifier} target
 * @param {import('estree').Identifier} source
 */
export function with_loc(target, source) {
	if (source.loc) {
		return { ...target, loc: source.loc };
	}
	return target;
}
 
/**
 * @param {import("estree").Pattern} node
 * @param {import("zimmerframe").Context<import("#compiler").SvelteNode, import("./types").ComponentClientTransformState>} context
 * @returns {{ id: import("estree").Pattern, declarations: null | import("estree").Statement[] }}
 */
export function create_derived_block_argument(node, context) {
	if (node.type === 'Identifier') {
		return { id: node, declarations: null };
	}
 
	const pattern = /** @type {import('estree').Pattern} */ (context.visit(node));
	const identifiers = extract_identifiers(node);
 
	const id = b.id('$$source');
	const value = b.id('$$value');
 
	const block = b.block([
		b.var(pattern, b.call('$.get', id)),
		b.return(b.object(identifiers.map((identifier) => b.prop('init', identifier, identifier))))
	]);
 
	const declarations = [b.var(value, create_derived(context.state, b.thunk(block)))];
 
	for (const id of identifiers) {
		declarations.push(
			b.var(id, create_derived(context.state, b.thunk(b.member(b.call('$.get', value), id))))
		);
	}
 
	return { id, declarations };
}
 
/**
 * Svelte legacy mode should use safe equals in most places, runes mode shouldn't
 * @param {import('./types.js').ComponentClientTransformState} state
 * @param {import('estree').Expression} arg
 */
export function create_derived(state, arg) {
	return b.call(state.analysis.runes ? '$.derived' : '$.derived_safe_equal', arg);
}