WIP

Author: Rich-Harris

packages/svelte/src/internal/client/error-handling.js

@@ -77,7 +77,7 @@ function should_rethrow_error(effect) {
  * @param {Error} error
  * @param {Effect} effect
  */
-function adjust_error(error, effect) {
+export function adjust_error(error, effect) {
 	if (adjusted_errors.has(error)) return;
 	adjusted_errors.add(error);
 

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

@@ -40,7 +40,7 @@ import {
 	set_component_context,
 	set_dev_current_component_function
 } from './context.js';
-import { handle_error, invoke_error_boundary } from './error-handling.js';
+import { adjust_error, handle_error, invoke_error_boundary } from './error-handling.js';
 
 let is_flushing = false;
 
@@ -345,18 +345,17 @@ export function update_reaction(reaction) {
 
 		return result;
 	} catch (error) {
-		// TODO think we can just use active_effect here?
-		var effect = get_effect(reaction);
-
-		if (effect) {
-			if ((effect.f & EFFECT_RAN) !== 0) {
-				invoke_error_boundary(error, effect);
-			} else if ((effect.f & BOUNDARY_EFFECT) !== 0) {
-				// invoke directly
-				effect.fn(error);
-			} else {
-				throw error;
-			}
+		var effect = /** @type {Effect} */ (active_effect);
+
+		if (DEV && error instanceof Error) {
+			adjust_error(error, effect);
+		}
+
+		if ((effect.f & EFFECT_RAN) !== 0) {
+			invoke_error_boundary(error, effect);
+		} else if ((effect.f & BOUNDARY_EFFECT) !== 0) {
+			// invoke directly
+			effect.fn(error);
 		} else {
 			throw error;
 		}