From 35adca7f8cfa7073f0547ef9c24ca414077e38a3 Mon Sep 17 00:00:00 2001
From: Dmitry Lavrinovich <52966626+dmlvr@users.noreply.github.com>
Date: Wed, 13 May 2026 16:20:24 +0300
Subject: [PATCH] T1328518 - Scrollable - Simulated scrolling breaks after an
 unhandled JavaScript exception (#33565)

---
 .../ui/scroll_view/scrollable.simulated.ts    |  7 +-
 .../scrollable.actions.tests.js               | 96 +++++++++++++++++++
 2 files changed, 102 insertions(+), 1 deletion(-)

diff --git a/packages/devextreme/js/__internal/ui/scroll_view/scrollable.simulated.ts b/packages/devextreme/js/__internal/ui/scroll_view/scrollable.simulated.ts
index 5ceec5b1c3ad..52236c88c24d 100644
--- a/packages/devextreme/js/__internal/ui/scroll_view/scrollable.simulated.ts
+++ b/packages/devextreme/js/__internal/ui/scroll_view/scrollable.simulated.ts
@@ -29,6 +29,7 @@ import { getHeight, getWidth } from '@js/core/utils/size';
 import { isDefined } from '@js/core/utils/type';
 import { getWindow, hasWindow } from '@js/core/utils/window';
 import type { ScrollEvent } from '@js/ui/scroll_view';
+import { logger } from '@ts/core/utils/m_console';
 import type { ActionConfig } from '@ts/core/widget/component';
 import Animator from '@ts/ui/scroll_view/animator';
 import type { ScrollViewScroller } from '@ts/ui/scroll_view/scroll_view.simulated';
@@ -1094,7 +1095,11 @@ export class SimulatedStrategy<
     const actionHandler = this._createActionByOption(optionName);
 
     return (...args: unknown[]) => {
-      actionHandler(extend(this._createActionArgs(), args));
+      try {
+        actionHandler(extend(this._createActionArgs(), args));
+      } catch (e) {
+        logger.error(e);
+      }
     };
   }
 
diff --git a/packages/devextreme/testing/tests/DevExpress.ui.widgets/scrollableParts/scrollable.actions.tests.js b/packages/devextreme/testing/tests/DevExpress.ui.widgets/scrollableParts/scrollable.actions.tests.js
index f7a78f7e2353..c7f2f6363390 100644
--- a/packages/devextreme/testing/tests/DevExpress.ui.widgets/scrollableParts/scrollable.actions.tests.js
+++ b/packages/devextreme/testing/tests/DevExpress.ui.widgets/scrollableParts/scrollable.actions.tests.js
@@ -404,3 +404,99 @@ QUnit.test('update', function(assert) {
         .move(0, moveDistance)
         .up();
 });
+
+QUnit.module('actions stay functional after callback errors', moduleConfig);
+
+[
+    {
+        callbackName: 'onScroll',
+        message: 'onScroll error does not break subsequent actions',
+        configure: function(callback) {
+            const $scrollable = $('#scrollable').dxScrollable({
+                useNative: false,
+                inertiaEnabled: false,
+                bounceEnabled: false,
+                onScroll: callback,
+            });
+
+            return {
+                trigger: function() {
+                    pointerMock($scrollable.find('.' + SCROLLABLE_CONTENT_CLASS))
+                        .start()
+                        .down()
+                        .move(0, -10)
+                        .up();
+                },
+            };
+        },
+    },
+    {
+        callbackName: 'onUpdated',
+        message: 'onUpdated error does not break subsequent actions',
+        configure: function(callback) {
+            const scrollable = $('#scrollable').dxScrollable({
+                useNative: false,
+                onUpdated: callback,
+            }).dxScrollable('instance');
+
+            return {
+                trigger: function() {
+                    scrollable.update();
+                },
+            };
+        },
+    },
+    {
+        callbackName: 'onStart',
+        message: 'onStart error does not break subsequent actions',
+        configure: function(callback) {
+            const scrollable = $('#scrollable').dxScrollable({
+                useNative: false,
+                onStart: callback,
+            }).dxScrollable('instance');
+
+            return {
+                trigger: function() {
+                    scrollable.scrollBy({ top: 10 });
+                },
+            };
+        },
+    },
+    {
+        callbackName: 'onEnd',
+        message: 'onEnd error does not break subsequent actions',
+        configure: function(callback) {
+            const scrollable = $('#scrollable').dxScrollable({
+                useNative: false,
+                onEnd: callback,
+            }).dxScrollable('instance');
+
+            return {
+                trigger: function() {
+                    scrollable.scrollBy({ top: 10 });
+                },
+            };
+        },
+    },
+].forEach((testCase) => {
+    QUnit.test(testCase.message, function(assert) {
+        let callbackCallCount = 0;
+
+        const { trigger } = testCase.configure(function() {
+            callbackCallCount++;
+            throw new Error(testCase.callbackName + ' error');
+        });
+
+        callbackCallCount = 0;
+
+        trigger();
+        trigger();
+
+        assert.strictEqual(
+            callbackCallCount,
+            2,
+            `${testCase.callbackName}: component remained functional and handled both actions after callback errors`,
+        );
+    });
+});
+