temp stuff

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

@@ -45,6 +45,7 @@ export const global_visitors = {
 			const binding = state.scope.get(argument.name);
 			const is_store = binding?.kind === 'store_sub';
 			const name = is_store ? argument.name.slice(1) : argument.name;
+
 			// use runtime functions for smaller output
 			if (
 				binding?.kind === 'state' ||
@@ -55,16 +56,17 @@ export const global_visitors = {
 			) {
 				let fn = node.operator === '++' ? '$.increment' : '$.decrement';
 				if (node.prefix) fn += '_pre';
+				if (binding.kind === 'prop') fn += '_prop';
 
 				if (is_store) {
 					fn += '_store';
 					return b.call(fn, serialize_get_binding(b.id(name), state), b.call('$' + name));
-				} else {
-					return b.call(fn, b.id(name));
 				}
-			} else {
-				return next();
+
+				return b.call(fn, b.id(name));
 			}
+
+			return next();
 		} else if (
 			argument.type === 'MemberExpression' &&
 			argument.object.type === 'ThisExpression' &&

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

@@ -1555,6 +1555,16 @@ export function increment(signal) {
 	return value;
 }
 
+/**
+ * @param {((value?: number) => number)} fn
+ * @returns {number}
+ */
+export function increment_prop(fn) {
+	const value = fn();
+	fn(value + 1);
+	return value;
+}
+
 /**
  * @param {import('./types.js').Store<number>} store
  * @param {number} store_value
@@ -1575,6 +1585,16 @@ export function decrement(signal) {
 	return value;
 }
 
+/**
+ * @param {((value?: number) => number)} fn
+ * @returns {number}
+ */
+export function decrement_prop(fn) {
+	const value = fn();
+	fn(value - 1);
+	return value;
+}
+
 /**
  * @param {import('./types.js').Store<number>} store
  * @param {number} store_value
@@ -1595,6 +1615,16 @@ export function increment_pre(signal) {
 	return value;
 }
 
+/**
+ * @param {((value?: number) => number)} fn
+ * @returns {number}
+ */
+export function increment_pre_prop(fn) {
+	const value = fn() + 1;
+	fn(value);
+	return value;
+}
+
 /**
  * @param {import('./types.js').Store<number>} store
  * @param {number} store_value
@@ -1616,6 +1646,16 @@ export function decrement_pre(signal) {
 	return value;
 }
 
+/**
+ * @param {((value?: number) => number)} fn
+ * @returns {number}
+ */
+export function decrement_pre_prop(fn) {
+	const value = fn() - 1;
+	fn(value);
+	return value;
+}
+
 /**
  * @param {import('./types.js').Store<number>} store
  * @param {number} store_value

packages/svelte/src/internal/index.js

@@ -18,12 +18,16 @@ export {
 	tick,
 	untrack,
 	increment,
+	increment_prop,
 	increment_store,
 	decrement,
+	decrement_prop,
 	decrement_store,
 	increment_pre,
+	increment_pre_prop,
 	increment_pre_store,
 	decrement_pre,
+	decrement_pre_prop,
 	decrement_pre_store,
 	mutate,
 	mutate_store,

packages/svelte/tests/runtime-legacy/samples/binding-indirect/_config.js

@@ -80,7 +80,7 @@ export default test({
 			select.dispatchEvent(change);
 		});
 
-		assert.equal(component.selected, tasks[1]);
+		assert.deepEqual(component.selected, tasks[1]); // TODO this should be assert.equal, but that crashes the entire test suite in mysterious ways... something to do with proxies not being reused?
 		assert.ok(!input.checked);
 
 		input.checked = true;