ugh

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

@@ -64,7 +64,7 @@ export function visit_component(node, context) {
 	// If the component has a slot attribute — `<Foo slot="whatever" .../>` —
 	// then `let:` directives apply to other attributes, instead of just the
 	// top-level contents of the component. Yes, this is very weird.
-	const default_state = !!determine_slot(node)
+	const default_state = determine_slot(node)
 		? context.state
 		: { ...context.state, scope: node.metadata.scopes.default };
 

packages/svelte/src/compiler/phases/scope.js

@@ -303,7 +303,7 @@ export function create_scopes(ast, root, allow_reactive_declarations, parent) {
 			default: context.state.scope.child()
 		};
 
-		const default_state = !!determine_slot(node)
+		const default_state = determine_slot(node)
 			? context.state
 			: { scope: node.metadata.scopes.default };