only create source for state that is reassigned

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

@@ -240,11 +240,12 @@ export function client_component(source, analysis, options) {
 
 	const properties = analysis.exports.map(({ name, alias }) => {
 		const binding = analysis.instance.scope.get(name);
+		const is_source =
+			binding?.kind === 'state' && (!state.analysis.immutable || binding.reassigned);
+
 		// TODO This is always a getter because the `renamed-instance-exports` test wants it that way.
 		// Should we for code size reasons make it an init in runes mode and/or non-dev mode?
-		return b.get(alias ?? name, [
-			b.return(binding?.kind === 'state' ? b.call('$.get', b.id(name)) : b.id(name))
-		]);
+		return b.get(alias ?? name, [b.return(is_source ? b.call('$.get', b.id(name)) : b.id(name))]);
 	});
 
 	if (analysis.accessors) {

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

@@ -79,7 +79,8 @@ export function serialize_get_binding(node, state) {
 	}
 
 	if (
-		binding.kind === 'state' ||
+		(binding.kind === 'state' &&
+			(!state.analysis.immutable || state.analysis.accessors || binding.reassigned)) ||
 		binding.kind === 'derived' ||
 		binding.kind === 'prop' ||
 		binding.kind === 'rest_prop' ||

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

@@ -211,21 +211,28 @@ export const javascript_visitors_runes = {
 			}
 
 			const args = /** @type {import('estree').CallExpression} */ (init).arguments;
-			const value =
+			let value =
 				args.length === 0
 					? b.id('undefined')
 					: /** @type {import('estree').Expression} */ (visit(args[0]));
-			const opts = args[1] && /** @type {import('estree').Expression} */ (visit(args[1]));
 
 			if (declarator.id.type === 'Identifier') {
-				const callee = rune === '$state' ? '$.source' : '$.derived';
-				const arg =
-					rune === '$state'
-						? should_proxy(value)
-							? b.call('$.proxy', value)
-							: value
-						: b.thunk(value);
-				declarations.push(b.declarator(declarator.id, b.call(callee, arg, opts)));
+				if (rune === '$state') {
+					const binding = /** @type {import('#compiler').Binding} */ (
+						state.scope.get(declarator.id.name)
+					);
+					if (should_proxy(value)) {
+						value = b.call('$.proxy', value);
+					}
+
+					if (!state.analysis.immutable || state.analysis.accessors || binding.reassigned) {
+						value = b.call('$.source', value);
+					}
+				} else {
+					value = b.call('$.derived', b.thunk(value));
+				}
+
+				declarations.push(b.declarator(declarator.id, value));
 				continue;
 			}
 

packages/svelte/tests/snapshot/samples/dynamic-attributes-casing/_expected/client/main.svelte.js

@@ -9,8 +9,8 @@ export default function Main($$anchor, $$props) {
 	$.push($$props, true);
 
 	// needs to be a snapshot test because jsdom does auto-correct the attribute casing
-	let x = $.source('test');
-	let y = $.source(() => 'test');
+	let x = 'test';
+	let y = () => 'test';
 	/* Init */
 	var fragment = $.open_frag($$anchor, false, frag);
 	var node = $.child_frag(fragment);
@@ -21,28 +21,28 @@ export default function Main($$anchor, $$props) {
 	var custom_element_1 = $.sibling($.sibling(svg_1));
 
 	/* Update */
-	$.attr_effect(div, "foobar", () => $.get(y)());
-	$.attr_effect(svg_1, "viewBox", () => $.get(y)());
-	$.set_custom_element_data_effect(custom_element_1, "fooBar", () => $.get(y)());
+	$.attr_effect(div, "foobar", () => y());
+	$.attr_effect(svg_1, "viewBox", () => y());
+	$.set_custom_element_data_effect(custom_element_1, "fooBar", () => y());
 
 	var node_foobar;
 	var svg_viewBox;
 	var custom_element_fooBar;
 
 	$.render_effect(() => {
-		if (node_foobar !== (node_foobar = $.get(x))) {
+		if (node_foobar !== (node_foobar = x)) {
 			$.attr(node, "foobar", node_foobar);
 		}
 
-		if (svg_viewBox !== (svg_viewBox = $.get(x))) {
+		if (svg_viewBox !== (svg_viewBox = x)) {
 			$.attr(svg, "viewBox", svg_viewBox);
 		}
 
-		if (custom_element_fooBar !== (custom_element_fooBar = $.get(x))) {
+		if (custom_element_fooBar !== (custom_element_fooBar = x)) {
 			$.set_custom_element_data(custom_element, "fooBar", custom_element_fooBar);
 		}
 	});
 
 	$.close_frag($$anchor, fragment);
 	$.pop();
-}
+}

packages/svelte/tests/snapshot/samples/export-state/_expected/client/index.svelte.js

@@ -0,0 +1,4 @@
+/* index.svelte.js generated by Svelte VERSION */
+import * as $ from "svelte/internal";
+
+export const object = $.proxy({ ok: true });

packages/svelte/tests/snapshot/samples/export-state/_expected/server/index.svelte.js

@@ -0,0 +1,5 @@
+/* index.svelte.js generated by Svelte VERSION */
+import * as $ from "svelte/internal/server";
+
+export const object = { ok: true };
+

packages/svelte/tests/snapshot/samples/export-state/index.svelte.js

@@ -0,0 +1,3 @@
+export const object = $state({
+	ok: true
+});