try adding support for individual property invalidation, might revert later

packages/svelte/src/compiler/phases/2-analyze/visitors/CallExpression.js

@@ -1,9 +1,9 @@
-/** @import { ArrowFunctionExpression, CallExpression, Expression, FunctionDeclaration, FunctionExpression, Identifier, VariableDeclarator } from 'estree' */
+/** @import { ArrowFunctionExpression, CallExpression, Expression, FunctionDeclaration, FunctionExpression, Identifier, MemberExpression, VariableDeclarator } from 'estree' */
 /** @import { AST } from '#compiler' */
 /** @import { Context } from '../types' */
 import { get_rune } from '../../scope.js';
 import * as e from '../../../errors.js';
-import { get_parent, unwrap_optional } from '../../../utils/ast.js';
+import { get_parent, object, unwrap_optional } from '../../../utils/ast.js';
 import { is_pure, is_safe_identifier } from './shared/utils.js';
 import { dev, locate_node, source } from '../../../state.js';
 import * as b from '../../../utils/builders.js';
@@ -121,10 +121,18 @@ export function CallExpression(node, context) {
 				}
 				if (arg.type === 'MemberExpression') {
 					if (arg.object.type !== 'ThisExpression') {
-						e.state_invalidate_nonreactive_argument(node);
+						const obj = object((arg = /** @type {MemberExpression} */ (context.visit(arg))));
+						if (obj?.type === 'Identifier') {
+							// there isn't really a good way to tell because of stuff like `notproxied = proxied`
+							break;
+						} else if (obj?.type !== 'ThisExpression') {
+							e.state_invalidate_nonreactive_argument(node);
+						}
+					} else if (arg.computed) {
+						e.state_invalidate_invalid_this_property(node);
 					}
 					const class_body = context.path.findLast((parent) => parent.type === 'ClassBody');
-					if (arg.computed || !class_body) {
+					if (!class_body) {
 						e.state_invalidate_invalid_this_property(node);
 					}
 					const possible_this_bindings = context.path.filter((parent, index) => {

packages/svelte/src/compiler/phases/3-transform/client/visitors/CallExpression.js

@@ -1,10 +1,11 @@
-/** @import { CallExpression, Expression } from 'estree' */
+/** @import { CallExpression, Expression, Identifier } from 'estree' */
 /** @import { Context } from '../types' */
 import { dev, is_ignored } from '../../../../state.js';
 import * as b from '../../../../utils/builders.js';
 import { get_rune } from '../../../scope.js';
 import { transform_inspect_rune } from '../../utils.js';
 import * as e from '../../../../errors.js';
+import { object } from '../../../../utils/ast.js';
 
 /**
  * @param {CallExpression} node
@@ -29,20 +30,32 @@ export function CallExpression(node, context) {
 			if (node.arguments[0].type === 'Identifier') {
 				return b.call('$.invalidate', node.arguments[0]);
 			} else if (node.arguments[0].type === 'MemberExpression') {
-				const { property } = node.arguments[0];
-				let field;
-				switch (property.type) {
-					case 'Identifier':
-						field = context.state.public_state.get(property.name);
-						break;
-					case 'PrivateIdentifier':
-						field = context.state.private_state.get(property.name);
-						break;
+				const { object: obj, property } = node.arguments[0];
+				const root = object(node.arguments[0]);
+				if (obj.type === 'ThisExpression') {
+					let field;
+					switch (property.type) {
+						case 'Identifier':
+							field = context.state.public_state.get(property.name);
+							break;
+						case 'PrivateIdentifier':
+							field = context.state.private_state.get(property.name);
+							break;
+					}
+					if (!field || (field.kind !== 'state' && field.kind !== 'raw_state')) {
+						e.state_invalidate_nonreactive_argument(node);
+					}
+					return b.call('$.invalidate', b.member(b.this, field.id));
 				}
-				if (!field || (field.kind !== 'state' && field.kind !== 'raw_state')) {
-					e.state_invalidate_nonreactive_argument(node);
-				}
-				return b.call('$.invalidate', b.member(b.this, field.id));
+				/** @type {Expression[]} */
+				const source_args = /** @type {Expression[]} */ ([
+					context.visit(obj),
+					node.arguments[0].computed
+						? context.visit(property)
+						: b.literal(/** @type {Identifier} */ (property).name)
+				]);
+				const arg = b.call('$.lookup_source', ...source_args);
+				return b.call('$.invalidate', arg);
 			}
 
 		case '$effect.root':

packages/svelte/src/internal/client/constants.js

@@ -25,3 +25,4 @@ export const EFFECT_IS_UPDATING = 1 << 21;
 export const STATE_SYMBOL = Symbol('$state');
 export const LEGACY_PROPS = Symbol('legacy props');
 export const LOADING_ATTR_SYMBOL = Symbol('');
+export const PROXY_SOURCES = Symbol('proxy sources');

packages/svelte/src/internal/client/index.js

@@ -148,7 +148,7 @@ export {
 } from './runtime.js';
 export { validate_binding, validate_each_keys } from './validate.js';
 export { raf } from './timing.js';
-export { proxy } from './proxy.js';
+export { proxy, lookup_source } from './proxy.js';
 export { create_custom_element } from './dom/elements/custom-element.js';
 export {
 	child,

packages/svelte/src/internal/client/proxy.js

@@ -9,7 +9,7 @@ import {
 	object_prototype
 } from '../shared/utils.js';
 import { state as source, set } from './reactivity/sources.js';
-import { STATE_SYMBOL } from './constants.js';
+import { STATE_SYMBOL, PROXY_SOURCES } from './constants.js';
 import { UNINITIALIZED } from '../../constants.js';
 import * as e from './errors.js';
 import { get_stack } from './dev/tracing.js';
@@ -124,6 +124,10 @@ export function proxy(value) {
 				return value;
 			}
 
+			if (prop === PROXY_SOURCES) {
+				return sources;
+			}
+
 			var s = sources.get(prop);
 			var exists = prop in target;
 
@@ -165,7 +169,7 @@ export function proxy(value) {
 		},
 
 		has(target, prop) {
-			if (prop === STATE_SYMBOL) {
+			if (prop === STATE_SYMBOL || prop === PROXY_SOURCES) {
 				return true;
 			}
 
@@ -317,3 +321,22 @@ export function get_proxied_value(value) {
 export function is(a, b) {
 	return Object.is(get_proxied_value(a), get_proxied_value(b));
 }
+
+/**
+ * @param {Record<string | symbol, any>} object
+ * @param {string | symbol} property
+ * @returns {Source | null}
+ */
+export function lookup_source(object, property) {
+	if (typeof object !== 'object' || object === null) return null;
+	if (STATE_SYMBOL in object) {
+		if (property in object) {
+			/** @type {Map<string | symbol, Source>} */
+			const sources = object[PROXY_SOURCES];
+			if (sources.has(property)) {
+				return /** @type {Source} */ (sources.get(property));
+			}
+		}
+	}
+	return null;
+}

packages/svelte/src/internal/client/reactivity/sources.js

@@ -221,9 +221,12 @@ export function internal_set(source, value) {
 }
 
 /**
- * @param {Source} source
+ * @param {Source | null} source
  */
 export function invalidate(source) {
+	if (source === null) {
+		return;
+	}
 	if (
 		active_reaction !== null &&
 		!untracking &&