All files / src/internal/client/reactivity props.js

96.75% Statements 387/400
93.69% Branches 104/111
92.59% Functions 25/27
96.66% Lines 377/390

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 4042x 2x             2x 2x 2x 2x               2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 44x 44x 44x 44x 2x 2x 2x 2x 2x 2x 2x 6x 6x 6x 6x 2x 2x 2x 2x 2x 2x 2x 2x 26x 26x 2x 2x             2x 2x 26x 26x 26x 26x 26x 26x 26x 26x 2x 2x     2x 2x 37x 37x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 36x 36x 36x 36x 36x 2x 2x 2x 2x 2x 2x 2x 1114x 1114x 1114x 2x 2x 16x 8x 8x 8x 8x 8x 18x 18x 8x 8x 8x 8x 8x 16x 16x 16x 16x 2x 2x 524x 524x 524x 524x 524x 524x 524x 524x 2x 2x 4x 4x 2x 2x 2x 2x 2x 438x 438x 2x 2x 304x 304x 2x 2x 2x 2x 2x 2x 2x 2x 68x 68x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 1082x 1082x 1754x 1754x 1754x 1754x 2x 2x 128x 128x 188x 188x 188x 126x 126x           126x 126x 188x 2x 2x 384x 534x 534x 534x 40x 40x 2x 2x 120x 120x 120x 120x 234x 234x 636x 636x 226x 120x 120x 120x 2x 2x 2x 2x 2x 2x 2x 68x 68x 2x 2x 2x 2x 2x 2x 8719x 8719x 8719x 8719x 8719x 8x 8x 8719x 8719x 8719x 8719x 8719x 8719x 8719x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 14645x 14645x 14645x 14645x 14645x 14645x 14645x 14645x 14645x 14645x 14645x 14645x 14645x 2094x 2094x 1977x 1977x 471x 1977x 1506x 1506x 1977x 2094x 2094x 14645x 14645x 14645x 1926x 2x 2x 1924x 1924x 1926x 1926x 14643x 14643x 14643x 14645x 10176x 10668x 10668x 10498x 10498x 10498x 10176x 14645x 4467x 4467x 4467x 4467x 4467x 4467x 4467x 9587x 9587x 9587x 4467x 4467x 14643x 14643x 14645x 10091x 10091x 4552x 4552x 4552x 14634x 300x 300x 1130x 182x 182x 182x 182x 182x 158x 158x 182x 1130x 948x 948x 300x 300x 4252x 4252x 4252x 4252x 4252x 4252x 4252x 4252x 4252x 4252x 4252x 4252x 8737x 8737x 8737x 8737x 3738x 3738x 3738x 3738x 4999x 4999x 4999x 4252x 4252x 4252x 14634x 4252x 4252x 21268x 21268x 21268x 21268x 21268x 142x 142x 142x 142x 142x 142x 142x 142x 21268x 21268x 3818x 3818x 3818x 3730x 3730x 3730x 3730x 3730x 1543x 1543x 3730x 3730x 3818x 3818x 3818x 17450x 17450x 4252x 4252x  
/** @import { Source } from './types.js' */
import { DEV } from 'esm-env';
import {
	PROPS_IS_BINDABLE,
	PROPS_IS_IMMUTABLE,
	PROPS_IS_LAZY_INITIAL,
	PROPS_IS_RUNES,
	PROPS_IS_UPDATED
} from '../../../constants.js';
import { get_descriptor, is_function } from '../../shared/utils.js';
import { mutable_source, set, source } from './sources.js';
import { derived, derived_safe_equal } from './deriveds.js';
import {
	active_effect,
	get,
	is_signals_recorded,
	set_active_effect,
	untrack,
	update
} from '../runtime.js';
import { safe_equals } from './equality.js';
import * as e from '../errors.js';
import { BRANCH_EFFECT, LEGACY_DERIVED_PROP, ROOT_EFFECT } from '../constants.js';
import { proxy } from '../proxy.js';
 
/**
 * @param {((value?: number) => number)} fn
 * @param {1 | -1} [d]
 * @returns {number}
 */
export function update_prop(fn, d = 1) {
	const value = fn();
	fn(value + d);
	return value;
}
 
/**
 * @param {((value?: number) => number)} fn
 * @param {1 | -1} [d]
 * @returns {number}
 */
export function update_pre_prop(fn, d = 1) {
	const value = fn() + d;
	fn(value);
	return value;
}
 
/**
 * The proxy handler for rest props (i.e. `const { x, ...rest } = $props()`).
 * Is passed the full `$$props` object and excludes the named props.
 * @type {ProxyHandler<{ props: Record<string | symbol, unknown>, exclude: Array<string | symbol>, name?: string }>}}
 */
const rest_props_handler = {
	get(target, key) {
		if (target.exclude.includes(key)) return;
		return target.props[key];
	},
	set(target, key) {
		if (DEV) {
			// TODO should this happen in prod too?
			e.props_rest_readonly(`${target.name}.${String(key)}`);
		}

		return false;
	},
	getOwnPropertyDescriptor(target, key) {
		if (target.exclude.includes(key)) return;
		if (key in target.props) {
			return {
				enumerable: true,
				configurable: true,
				value: target.props[key]
			};
		}
	},
	has(target, key) {
		if (target.exclude.includes(key)) return false;
		return key in target.props;
	},
	ownKeys(target) {
		return Reflect.ownKeys(target.props).filter((key) => !target.exclude.includes(key));
	}
};
 
/**
 * @param {Record<string, unknown>} props
 * @param {string[]} exclude
 * @param {string} [name]
 * @returns {Record<string, unknown>}
 */
/*#__NO_SIDE_EFFECTS__*/
export function rest_props(props, exclude, name) {
	return new Proxy(
		DEV ? { props, exclude, name, other: {}, to_proxy: [] } : { props, exclude },
		rest_props_handler
	);
}
 
/**
 * The proxy handler for legacy $$restProps and $$props
 * @type {ProxyHandler<{ props: Record<string | symbol, unknown>, exclude: Array<string | symbol>, special: Record<string | symbol, (v?: unknown) => unknown>, version: Source<number> }>}}
 */
const legacy_rest_props_handler = {
	get(target, key) {
		if (target.exclude.includes(key)) return;
		get(target.version);
		return key in target.special ? target.special[key]() : target.props[key];
	},
	set(target, key, value) {
		if (!(key in target.special)) {
			// Handle props that can temporarily get out of sync with the parent
			/** @type {Record<string, (v?: unknown) => unknown>} */
			target.special[key] = prop(
				{
					get [key]() {
						return target.props[key];
					}
				},
				/** @type {string} */ (key),
				PROPS_IS_UPDATED
			);
		}
 
		target.special[key](value);
		update(target.version); // $$props is coarse-grained: when $$props.x is updated, usages of $$props.y etc are also rerun
		return true;
	},
	getOwnPropertyDescriptor(target, key) {
		if (target.exclude.includes(key)) return;
		if (key in target.props) {
			return {
				enumerable: true,
				configurable: true,
				value: target.props[key]
			};
		}
	},
	deleteProperty(target, key) {
		// Svelte 4 allowed for deletions on $$restProps
		if (target.exclude.includes(key)) return true;
		target.exclude.push(key);
		update(target.version);
		return true;
	},
	has(target, key) {
		if (target.exclude.includes(key)) return false;
		return key in target.props;
	},
	ownKeys(target) {
		return Reflect.ownKeys(target.props).filter((key) => !target.exclude.includes(key));
	}
};
 
/**
 * @param {Record<string, unknown>} props
 * @param {string[]} exclude
 * @returns {Record<string, unknown>}
 */
export function legacy_rest_props(props, exclude) {
	return new Proxy({ props, exclude, special: {}, version: source(0) }, legacy_rest_props_handler);
}
 
/**
 * The proxy handler for spread props. Handles the incoming array of props
 * that looks like `() => { dynamic: props }, { static: prop }, ..` and wraps
 * them so that the whole thing is passed to the component as the `$$props` argument.
 * @template {Record<string | symbol, unknown>} T
 * @type {ProxyHandler<{ props: Array<T | (() => T)> }>}}
 */
const spread_props_handler = {
	get(target, key) {
		let i = target.props.length;
		while (i--) {
			let p = target.props[i];
			if (is_function(p)) p = p();
			if (typeof p === 'object' && p !== null && key in p) return p[key];
		}
	},
	getOwnPropertyDescriptor(target, key) {
		let i = target.props.length;
		while (i--) {
			let p = target.props[i];
			if (is_function(p)) p = p();
			if (typeof p === 'object' && p !== null && key in p) {
				const descriptor = get_descriptor(p, key);
				if (descriptor && !descriptor.configurable) {
					// Prevent a "Non-configurability Report Error": The target is an array, it does
					// not actually contain this property. If it is now described as non-configurable,
					// the proxy throws a validation error. Setting it to true avoids that.
					descriptor.configurable = true;
				}
				return descriptor;
			}
		}
	},
	has(target, key) {
		for (let p of target.props) {
			if (is_function(p)) p = p();
			if (p != null && key in p) return true;
		}
 
		return false;
	},
	ownKeys(target) {
		/** @type {Array<string | symbol>} */
		const keys = [];
 
		for (let p of target.props) {
			if (is_function(p)) p = p();
			for (const key in p) {
				if (!keys.includes(key)) keys.push(key);
			}
		}
 
		return keys;
	}
};
 
/**
 * @param {Array<Record<string, unknown> | (() => Record<string, unknown>)>} props
 * @returns {any}
 */
export function spread_props(...props) {
	return new Proxy({ props }, spread_props_handler);
}
 
/**
 * @template T
 * @param {() => T} fn
 * @returns {T}
 */
function with_parent_branch(fn) {
	var effect = active_effect;
	var previous_effect = active_effect;
 
	while (effect !== null && (effect.f & (BRANCH_EFFECT | ROOT_EFFECT)) === 0) {
		effect = effect.parent;
	}
	try {
		set_active_effect(effect);
		return fn();
	} finally {
		set_active_effect(previous_effect);
	}
}
 
/**
 * This function is responsible for synchronizing a possibly bound prop with the inner component state.
 * It is used whenever the compiler sees that the component writes to the prop, or when it has a default prop_value.
 * @template V
 * @param {Record<string, unknown>} props
 * @param {string} key
 * @param {number} flags
 * @param {V | (() => V)} [fallback]
 * @returns {(() => V | ((arg: V) => V) | ((arg: V, mutation: boolean) => V))}
 */
export function prop(props, key, flags, fallback) {
	var immutable = (flags & PROPS_IS_IMMUTABLE) !== 0;
	var runes = (flags & PROPS_IS_RUNES) !== 0;
	var bindable = (flags & PROPS_IS_BINDABLE) !== 0;
	var lazy = (flags & PROPS_IS_LAZY_INITIAL) !== 0;
 
	var prop_value = /** @type {V} */ (props[key]);
	var setter = get_descriptor(props, key)?.set;
 
	var fallback_value = /** @type {V} */ (fallback);
	var fallback_dirty = true;
	var fallback_used = false;
 
	var get_fallback = () => {
		fallback_used = true;
		if (fallback_dirty) {
			fallback_dirty = false;
			if (lazy) {
				fallback_value = untrack(/** @type {() => V} */ (fallback));
			} else {
				fallback_value = /** @type {V} */ (fallback);
			}
		}
 
		return fallback_value;
	};
 
	if (prop_value === undefined && fallback !== undefined) {
		if (setter && runes) {
			e.props_invalid_value(key);
		}
 
		prop_value = get_fallback();
		if (setter) setter(prop_value);
	}
 
	/** @type {() => V} */
	var getter;
	if (runes) {
		getter = () => {
			var value = /** @type {V} */ (props[key]);
			if (value === undefined) return get_fallback();
			fallback_dirty = true;
			fallback_used = false;
			return value;
		};
	} else {
		// Svelte 4 did not trigger updates when a primitive value was updated to the same value.
		// Replicate that behavior through using a derived
		var derived_getter = with_parent_branch(() =>
			(immutable ? derived : derived_safe_equal)(() => /** @type {V} */ (props[key]))
		);
		derived_getter.f |= LEGACY_DERIVED_PROP;
		getter = () => {
			var value = get(derived_getter);
			if (value !== undefined) fallback_value = /** @type {V} */ (undefined);
			return value === undefined ? fallback_value : value;
		};
	}
 
	// easy mode — prop is never written to
	if ((flags & PROPS_IS_UPDATED) === 0) {
		return getter;
	}
 
	// intermediate mode — prop is written to, but the parent component had
	// `bind:foo` which means we can just call `$$props.foo = value` directly
	if (setter) {
		var legacy_parent = props.$$legacy;
		return function (/** @type {any} */ value, /** @type {boolean} */ mutation) {
			if (arguments.length > 0) {
				// We don't want to notify if the value was mutated and the parent is in runes mode.
				// In that case the state proxy (if it exists) should take care of the notification.
				// If the parent is not in runes mode, we need to notify on mutation, too, that the prop
				// has changed because the parent will not be able to detect the change otherwise.
				if (!runes || !mutation || legacy_parent) {
					/** @type {Function} */ (setter)(mutation ? getter() : value);
				}
				return value;
			} else {
				return getter();
			}
		};
	}
 
	// hard mode. this is where it gets ugly — the value in the child should
	// synchronize with the parent, but it should also be possible to temporarily
	// set the value to something else locally.
	var from_child = false;
	var was_from_child = false;
 
	// The derived returns the current value. The underlying mutable
	// source is written to from various places to persist this value.
	var inner_current_value = mutable_source(prop_value);
	var current_value = with_parent_branch(() =>
		derived(() => {
			var parent_value = getter();
			var child_value = get(inner_current_value);
 
			if (from_child) {
				from_child = false;
				was_from_child = true;
				return child_value;
			}
 
			was_from_child = false;
			return (inner_current_value.v = parent_value);
		})
	);
 
	if (!immutable) current_value.equals = safe_equals;
 
	return function (/** @type {any} */ value, /** @type {boolean} */ mutation) {
		var current = get(current_value);
 
		// legacy nonsense — need to ensure the source is invalidated when necessary
		// also needed for when handling inspect logic so we can inspect the correct source signal
		if (is_signals_recorded) {
			// set this so that we don't reset to the parent value if `d`
			// is invalidated because of `invalidate_inner_signals` (rather
			// than because the parent or child value changed)
			from_child = was_from_child;
			// invoke getters so that signals are picked up by `invalidate_inner_signals`
			getter();
			get(inner_current_value);
		}
 
		if (arguments.length > 0) {
			const new_value = mutation ? get(current_value) : runes && bindable ? proxy(value) : value;
 
			if (!current_value.equals(new_value)) {
				from_child = true;
				set(inner_current_value, new_value);
				// To ensure the fallback value is consistent when used with proxies, we
				// update the local fallback_value, but only if the fallback is actively used
				if (fallback_used && fallback_value !== undefined) {
					fallback_value = new_value;
				}
				get(current_value); // force a synchronisation immediately
			}
 
			return value;
		}
 
		return current;
	};
}