From 43c3d6348155fa2ed4d90dc22e0cbc27c7c45452 Mon Sep 17 00:00:00 2001
From: Ruslan Farkhutdinov <ruslan.farkhutdinov@devexpress.com>
Date: Mon, 20 Apr 2026 16:25:56 +0300
Subject: [PATCH 1/2] DateBox: Fix validation message not cleared when masked
 date returns to valid range (T1326750)

---
 .../__internal/ui/date_box/date_box.mask.ts   |  5 +++-
 .../datebox.mask.tests.js                     | 28 +++++++++++++++++++
 2 files changed, 32 insertions(+), 1 deletion(-)

diff --git a/packages/devextreme/js/__internal/ui/date_box/date_box.mask.ts b/packages/devextreme/js/__internal/ui/date_box/date_box.mask.ts
index 793ff01cd2d4..fa975ca576c5 100644
--- a/packages/devextreme/js/__internal/ui/date_box/date_box.mask.ts
+++ b/packages/devextreme/js/__internal/ui/date_box/date_box.mask.ts
@@ -717,9 +717,12 @@ class DateBoxMask extends DateBoxBase {
   }
 
   _fireChangeEvent(): void {
+    const { isValid, validationError } = this.option();
+    const isInvalidEditorSpecific = !isValid && validationError?.editorSpecific;
+
     this._clearSearchValue();
 
-    if (this._isValueDirty()) {
+    if (this._isValueDirty() || isInvalidEditorSpecific) {
       eventsEngine.triggerHandler(this._input(), { type: 'change' });
     }
   }
diff --git a/packages/devextreme/testing/tests/DevExpress.ui.widgets.editors/datebox.mask.tests.js b/packages/devextreme/testing/tests/DevExpress.ui.widgets.editors/datebox.mask.tests.js
index 8adbab8c1d6d..a59aa82941ed 100644
--- a/packages/devextreme/testing/tests/DevExpress.ui.widgets.editors/datebox.mask.tests.js
+++ b/packages/devextreme/testing/tests/DevExpress.ui.widgets.editors/datebox.mask.tests.js
@@ -1672,6 +1672,34 @@ module('Regression', () => {
 
         assert.strictEqual($input.val(), '12:34', 'both digits go to hours and minutes stay unchanged');
     });
+
+    QUnit.test('should be valid when date returns to valid range after out-of-range change (T1326750)', function(assert) {
+        const $dateBox = $('#dateBox').dxDateBox({
+            useMaskBehavior: true,
+            pickerType: 'calendar',
+            type: 'date',
+            displayFormat: 'dd-MM-yyyy',
+            value: new Date(2020, 2, 31),
+            min: new Date(2018, 3, 1),
+            max: new Date(2020, 2, 31),
+        });
+
+        const instance = $dateBox.dxDateBox('instance');
+        const $input = $dateBox.find(`.${TEXT_EDITOR_INPUT_CLASS}`);
+        const keyboard = keyboardMock($input, true);
+
+        keyboard.press('right').press('right');
+
+        keyboard.press('up');
+        keyboard.press('enter');
+
+        assert.strictEqual(instance.option('isValid'), false, 'should be invalid when year 2021 exceeds max date');
+
+        keyboard.press('down');
+        keyboard.press('enter');
+
+        assert.strictEqual(instance.option('isValid'), true, 'should be valid when year returns to 2020');
+    });
 });
 
 module('Caret moving', setupModule, () => {

From c690b97f36dc6e5d501478f1cb924c1b1805d060 Mon Sep 17 00:00:00 2001
From: Ruslan Farkhutdinov <ruslan.farkhutdinov@devexpress.com>
Date: Mon, 20 Apr 2026 16:57:15 +0300
Subject: [PATCH 2/2] DateBox: Move _hasEditorSpecificValidationError to a
 separate function

---
 .../js/__internal/ui/date_box/date_box.mask.ts           | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/packages/devextreme/js/__internal/ui/date_box/date_box.mask.ts b/packages/devextreme/js/__internal/ui/date_box/date_box.mask.ts
index fa975ca576c5..0a725c0ecb32 100644
--- a/packages/devextreme/js/__internal/ui/date_box/date_box.mask.ts
+++ b/packages/devextreme/js/__internal/ui/date_box/date_box.mask.ts
@@ -716,13 +716,16 @@ class DateBoxMask extends DateBoxBase {
     return this._maskValue?.getTime() !== value?.getTime();
   }
 
-  _fireChangeEvent(): void {
+  _hasEditorSpecificValidationError(): boolean {
     const { isValid, validationError } = this.option();
-    const isInvalidEditorSpecific = !isValid && validationError?.editorSpecific;
 
+    return !isValid && Boolean(validationError?.editorSpecific);
+  }
+
+  _fireChangeEvent(): void {
     this._clearSearchValue();
 
-    if (this._isValueDirty() || isInvalidEditorSpecific) {
+    if (this._isValueDirty() || this._hasEditorSpecificValidationError()) {
       eventsEngine.triggerHandler(this._input(), { type: 'change' });
     }
   }