add more test coverage

Author: trueadm

packages/svelte/src/internal/client/dom/blocks/boundary.js

@@ -59,7 +59,7 @@ export function boundary(node, boundary_fn, props) {
 	block(() => {
 		var boundary = /** @type {Effect} */ (active_effect);
 		var hydrate_open = hydrate_node;
-		var is_rendering_failed = false;
+		var is_creating_fallback = false;
 
 		// We re-use the effect's fn property to avoid allocation of an additional field
 		boundary.fn = (/** @type { Error }} */ error) => {
@@ -75,9 +75,9 @@ export function boundary(node, boundary_fn, props) {
 			}
 
 			// If we have nothing to capture the error then re-throw the error
-			// for another boundary to handle, additionaly, if we're rendering
+			// for another boundary to handle, additionaly, if we're creating
 			// the fallback and that too fails, then re-throw the error
-			if ((!onerror && !failed_snippet) || is_rendering_failed) {
+			if ((!onerror && !failed_snippet) || is_creating_fallback) {
 				throw error;
 			}
 
@@ -88,7 +88,7 @@ export function boundary(node, boundary_fn, props) {
 				}
 				with_boundary(boundary, () => {
 					boundary_effect = null;
-					is_rendering_failed = false;
+					is_creating_fallback = false;
 					boundary_effect = branch(() => boundary_fn(anchor));
 				});
 			};
@@ -104,7 +104,7 @@ export function boundary(node, boundary_fn, props) {
 				queue_micro_task(() => {
 					with_boundary(boundary, () => {
 						boundary_effect = null;
-						is_rendering_failed = true;
+						is_creating_fallback = true;
 						try {
 							boundary_effect = branch(() => {
 								failed_snippet(
@@ -116,7 +116,7 @@ export function boundary(node, boundary_fn, props) {
 						} catch (error) {
 							handle_error(/** @type {Error} */ (error), boundary, boundary.ctx);
 						}
-						is_rendering_failed = false;
+						is_creating_fallback = false;
 					});
 				});
 			}

packages/svelte/tests/runtime-runes/samples/error-boundary-16/Child.svelte

@@ -0,0 +1,13 @@
+<script>
+	let count = $state(0);
+
+	$effect.pre(() => {
+		if (count > 1) {
+			throw new Error('too high');
+		}
+	});
+</script>
+
+{count}
+
+<button onclick={() => count++}>+</button>

packages/svelte/tests/runtime-runes/samples/error-boundary-16/_config.js

@@ -0,0 +1,24 @@
+import { flushSync } from 'svelte';
+import { test } from '../../test';
+
+export default test({
+	test({ assert, target, logs }) {
+		let btn = target.querySelector('button');
+
+		btn?.click();
+		btn?.click();
+		flushSync();
+
+		assert.deepEqual(logs, ['error caught']);
+		assert.htmlEqual(target.innerHTML, `<div>An error occurred!</div>\n0\n<button>+</button>`);
+
+		btn = target.querySelector('button');
+
+		btn?.click();
+		btn?.click();
+		flushSync();
+
+		assert.deepEqual(logs, ['error caught', 'error caught']);
+		assert.htmlEqual(target.innerHTML, `<div>An error occurred!</div>\n0\n<button>+</button>`);
+	}
+});

packages/svelte/tests/runtime-runes/samples/error-boundary-16/main.svelte

@@ -0,0 +1,12 @@
+<script>
+	import Child from './Child.svelte';
+</script>
+
+<svelte:boundary onerror={(e) => console.log('error caught')}>
+	<Child />
+
+	{#snippet failed(err, reset)}
+		<div>An error occurred!</div>
+		<Child />
+	{/snippet}
+</svelte:boundary>