fix

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

@@ -270,13 +270,46 @@ export function invalidate(source) {
 	}
 	if (
 		active_reaction !== null &&
-		!untracking &&
+		// since we are untracking the function inside `$inspect.with` we need to add this check
+		// to ensure we error if state is set inside an inspect effect
+		(!untracking || (active_reaction.f & INSPECT_EFFECT) !== 0) &&
 		is_runes() &&
-		(active_reaction.f & (DERIVED | BLOCK_EFFECT)) !== 0 &&
+		(active_reaction.f & (DERIVED | BLOCK_EFFECT | ASYNC | INSPECT_EFFECT)) !== 0 &&
-		!reaction_sources?.includes(source)
+		!current_sources?.includes(source)
 	) {
 		e.state_unsafe_mutation();
 	}
+
+	if (DEV) {
+		if (tracing_mode_flag || active_effect !== null) {
+			const error = get_stack('UpdatedAt');
+
+			if (error !== null) {
+				source.updated ??= new Map();
+				let entry = source.updated.get(error.stack);
+
+				if (!entry) {
+					entry = { error, count: 0 };
+					source.updated.set(error.stack, entry);
+				}
+
+				entry.count++;
+			}
+		}
+
+		if (active_effect !== null) {
+			source.set_during_effect = true;
+		}
+	}
+
+	if ((source.f & DERIVED) !== 0) {
+		// if we are assigning to a dirty derived we set it to clean/maybe dirty but we also eagerly execute it to track the dependencies
+		if ((source.f & DIRTY) !== 0) {
+			execute_derived(/** @type {Derived} */ (source));
+		}
+		set_signal_status(source, (source.f & UNOWNED) === 0 ? CLEAN : MAYBE_DIRTY);
+	}
+
 	source.wv = increment_write_version();
 
 	mark_reactions(source, DIRTY);
@@ -298,21 +331,8 @@ export function invalidate(source) {
 		}
 	}
 
-	if (DEV && inspect_effects.size > 0) {
+	if (DEV && inspect_effects.size > 0 && !inspect_effects_deferred) {
-		const inspects = Array.from(inspect_effects);
+		flush_inspect_effects();
-
-		for (const effect of inspects) {
-			// Mark clean inspect-effects as maybe dirty and then check their dirtiness
-			// instead of just updating the effects - this way we avoid overfiring.
-			if ((effect.f & CLEAN) !== 0) {
-				set_signal_status(effect, MAYBE_DIRTY);
-			}
-			if (check_dirtiness(effect)) {
-				update_effect(effect);
-			}
-		}
-
-		inspect_effects.clear();
 	}
 }