Merge branch 'rxjs-support' of https://github.com/benlesh/svelte into benlesh-rxjs-support

src/internal/utils.js

@@ -48,7 +48,12 @@ export function validate_store(store, name) {
 }
 
 export function subscribe(component, store, callback) {
-	component.$$.on_destroy.push(store.subscribe(callback));
+	let unsub = store.subscribe(callback);
+	// Prevent memory leaks for RxJS users.
+	if (unsub.unsubscribe) {
+		unsub = () => unsub.unsubscribe();
+	}
+	component.$$.on_destroy.push(unsub);
 }
 
 export function create_slot(definition, ctx, fn) {
@@ -74,4 +79,4 @@ export function exclude_internal_props(props) {
 	const result = {};
 	for (const k in props) if (k[0] !== '$') result[k] = props[k];
 	return result;
-}
+}