fix: remove bindable prop validation (#14946)

.changeset/flat-otters-cheer.md

@@ -0,0 +1,5 @@
+---
+'svelte': patch
+---
+
+fix: remove bindable prop validation

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

@@ -299,28 +299,6 @@ export function client_component(analysis, options) {
 			(binding.kind === 'prop' || binding.kind === 'bindable_prop') && !name.startsWith('$$')
 	);
 
-	if (dev && analysis.runes) {
-		const exports = analysis.exports.map(({ name, alias }) => b.literal(alias ?? name));
-		/** @type {ESTree.Literal[]} */
-		const bindable = [];
-		for (const [name, binding] of properties) {
-			if (binding.kind === 'bindable_prop') {
-				bindable.push(b.literal(binding.prop_alias ?? name));
-			}
-		}
-		instance.body.unshift(
-			b.stmt(
-				b.call(
-					'$.validate_prop_bindings',
-					b.id('$$props'),
-					b.array(bindable),
-					b.array(exports),
-					b.id(`${analysis.name}`)
-				)
-			)
-		);
-	}
-
 	if (analysis.accessors) {
 		for (const [name, binding] of properties) {
 			const key = binding.prop_alias ?? name;

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

@@ -150,7 +150,7 @@ export {
 	setContext,
 	hasContext
 } from './runtime.js';
-export { validate_binding, validate_each_keys, validate_prop_bindings } from './validate.js';
+export { validate_binding, validate_each_keys } from './validate.js';
 export { raf } from './timing.js';
 export { proxy } from './proxy.js';
 export { create_custom_element } from './dom/elements/custom-element.js';

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

@@ -297,8 +297,10 @@ export function prop(props, key, flags, fallback) {
 	var is_entry_props = STATE_SYMBOL in props || LEGACY_PROPS in props;
 
 	var setter =
-		get_descriptor(props, key)?.set ??
+		(bindable &&
-		(is_entry_props && bindable && key in props ? (v) => (props[key] = v) : undefined);
+			(get_descriptor(props, key)?.set ??
+				(is_entry_props && key in props && ((v) => (props[key] = v))))) ||
+		undefined;
 
 	var fallback_value = /** @type {V} */ (fallback);
 	var fallback_dirty = true;

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

@@ -1,5 +1,5 @@
 import { dev_current_component_function } from './runtime.js';
-import { get_descriptor, is_array } from '../shared/utils.js';
+import { is_array } from '../shared/utils.js';
 import * as e from './errors.js';
 import { FILENAME } from '../../constants.js';
 import { render_effect } from './reactivity/effects.js';
@@ -38,29 +38,6 @@ export function validate_each_keys(collection, key_fn) {
 	});
 }
 
-/**
- * @param {Record<string, any>} $$props
- * @param {string[]} bindable
- * @param {string[]} exports
- * @param {Function & { [FILENAME]: string }} component
- */
-export function validate_prop_bindings($$props, bindable, exports, component) {
-	for (const key in $$props) {
-		var setter = get_descriptor($$props, key)?.set;
-		var name = component.name;
-
-		if (setter) {
-			if (exports.includes(key) && !bindable.includes(key)) {
-				e.bind_invalid_export(component[FILENAME], key, name);
-			}
-
-			if (!bindable.includes(key)) {
-				e.bind_not_bindable(key, component[FILENAME], name);
-			}
-		}
-	}
-}
-
 /**
  * @param {string} binding
  * @param {() => Record<string, any>} get_object

packages/svelte/tests/runtime-runes/samples/export-binding/_config.js

@@ -1,10 +0,0 @@
-import { test } from '../../test';
-
-export default test({
-	compileOptions: {
-		dev: true // to ensure we we catch the error
-	},
-	error:
-		'bind_invalid_export\n' +
-		'Component counter/index.svelte has an export named `increment` that a consumer component is trying to access using `bind:increment`, which is disallowed. Instead, use `bind:this` (e.g. `<Counter bind:this={component} />`) and then access the property on the bound component instance (e.g. `component.increment`)'
-});

packages/svelte/tests/runtime-runes/samples/export-binding/counter/index.svelte

@@ -1,8 +0,0 @@
-<script>
-	let count = $state(0);
-	export function increment() {
-		count++;
-	}
-</script>
-
-{count}

packages/svelte/tests/runtime-runes/samples/export-binding/main.svelte

@@ -1,7 +0,0 @@
-<script>
-    import Counter from './counter/index.svelte';
-    let increment;
-</script>
-
-<Counter bind:increment={increment} />
-<button onclick={increment}>increment</button>

packages/svelte/tests/runtime-runes/samples/props-not-bindable-spread/Counter.svelte

@@ -1,5 +0,0 @@
-<script>
-	let { ...rest } = $props();
-</script>
-
-{rest.count}

packages/svelte/tests/runtime-runes/samples/props-not-bindable-spread/_config.js

@@ -1,13 +0,0 @@
-import { test } from '../../test';
-
-export default test({
-	compileOptions: {
-		dev: true
-	},
-
-	html: '0',
-
-	error:
-		'bind_not_bindable\n' +
-		'A component is attempting to bind to a non-bindable property `count` belonging to Counter.svelte (i.e. `<Counter bind:count={...}>`). To mark a property as bindable: `let { count = $bindable() } = $props()`'
-});

packages/svelte/tests/runtime-runes/samples/props-not-bindable-spread/main.svelte

@@ -1,7 +0,0 @@
-<script>
-    import Counter from './Counter.svelte';
-
-    let count = $state(0);
-</script>
-
-<Counter bind:count />

packages/svelte/tests/runtime-runes/samples/props-not-bindable/Counter.svelte

@@ -1,5 +0,0 @@
-<script>
-	let { count } = $props();
-</script>
-
-{count}

packages/svelte/tests/runtime-runes/samples/props-not-bindable/_config.js

@@ -1,13 +0,0 @@
-import { test } from '../../test';
-
-export default test({
-	compileOptions: {
-		dev: true
-	},
-
-	html: '0',
-
-	error:
-		'bind_not_bindable\n' +
-		'A component is attempting to bind to a non-bindable property `count` belonging to Counter.svelte (i.e. `<Counter bind:count={...}>`). To mark a property as bindable: `let { count = $bindable() } = $props()`'
-});

packages/svelte/tests/runtime-runes/samples/props-not-bindable/main.svelte

@@ -1,7 +0,0 @@
-<script>
-    import Counter from './Counter.svelte';
-
-    let count = $state(0);
-</script>
-
-<Counter bind:count />