#39169: Special Price To Date is wrongly validated on applySpecialPrice

- added unit tests

Author: KrasnoshchokBohdan

lib/internal/Magento/Framework/Stdlib/Test/Unit/DateTime/TimezoneTest.php

@@ -426,6 +426,42 @@ public function testScopeDate($date, string $timezone, string $locale, string $e
         $this->assertEquals($timezone, $scopeDate->getTimezone()->getName());
     }
 
+    /**
+     * @return void
+     * @throws \PHPUnit\Framework\MockObject\Exception
+     */
+    public function testIsScopeDateInInterval()
+    {
+        $scopeMock = $this->createMock(\Magento\Framework\App\ScopeInterface::class);
+        $this->scopeResolver->method('getScope')->willReturn($scopeMock);
+
+        $result = $this->getTimezone()->isScopeDateInInterval(
+            null,
+            '2025-04-01 00:00:00',
+            '2999-05-01 00:00:00',
+        );
+
+        $this->assertTrue($result);
+    }
+
+    /**
+     * @return void
+     * @throws \PHPUnit\Framework\MockObject\Exception
+     */
+    public function testIsScopeDateInIntervalFalse()
+    {
+        $scopeMock = $this->createMock(\Magento\Framework\App\ScopeInterface::class);
+        $this->scopeResolver->method('getScope')->willReturn($scopeMock);
+
+        $result = $this->getTimezone()->isScopeDateInInterval(
+            null,
+            '2025-03-01 00:00:00',
+            '2025-04-01 00:00:00',
+        );
+
+        $this->assertFalse($result);
+    }
+
     /**
      * @return array
      */