simplify

Author: Rich-Harris

packages/svelte/src/internal/client/dom/elements/actions.js

@@ -1,6 +1,5 @@
-import { effect } from '../../reactivity/effects.js';
-import { set, source } from '../../reactivity/sources.js';
-import { deep_read_state, get, untrack } from '../../runtime.js';
+import { effect, render_effect } from '../../reactivity/effects.js';
+import { deep_read_state, untrack } from '../../runtime.js';
 
 /**
  * @template P
@@ -10,54 +9,24 @@ import { deep_read_state, get, untrack } from '../../runtime.js';
  * @returns {void}
  */
 export function action(dom, action, get_value) {
-	/** @type {undefined | import('#client').ActionPayload<P>} */
-	var payload = undefined;
-	var version = source(0);
-	var inited = false;
-
-	/** @type {P} */
-	var value;
-
-	// The value needs to be calculated independent of the action body, as we only want to evaluate
-	// the payload of the action once – not when the value changes.
 	effect(() => {
-		get(version);
+		var payload = untrack(() => action(dom, get_value?.()) || {});
+		var update = payload?.update;
 
-		if (get_value) {
-			value = get_value();
-		}
+		if (get_value && update) {
+			var inited = false;
 
-		if (payload !== undefined) {
-			var update = payload.update;
-			if (typeof update === 'function') {
-				update(value);
-			}
-		}
-	});
+			render_effect(() => {
+				var value = get_value();
+				deep_read_state(value);
 
-	// Action could come from a prop, therefore could be a signal, therefore untrack
-	// TODO we could take advantage of this and enable https://github.com/sveltejs/svelte/issues/6942
-	effect(() => {
-		untrack(() => {
-			if (get_value) {
-				if (payload === undefined) {
-					payload = action(dom, value) || {};
-					if (payload?.update) {
-						// Action's update method is coarse-grained, i.e. when anything in the passed value changes, update.
-						// This works in legacy mode because of mutable_source being updated as a whole, but when using $state
-						// together with actions and mutation, it wouldn't notice the change without a deep read.
-						effect(() => {
-							deep_read_state(value);
-
-							if (inited) set(version, version.v + 1);
-							inited = true;
-						});
-					}
+				if (inited) {
+					/** @type {Function} */ (update)(value);
 				}
-			} else {
-				payload = action(dom);
-			}
-		});
+			});
+
+			inited = true;
+		}
 
 		return payload?.destroy;
 	});