diff --git a/tests/PHPStan/Rules/Arrays/NonexistentOffsetInArrayDimFetchRuleTest.php b/tests/PHPStan/Rules/Arrays/NonexistentOffsetInArrayDimFetchRuleTest.php
index 24d886f990..65a6886bab 100644
--- a/tests/PHPStan/Rules/Arrays/NonexistentOffsetInArrayDimFetchRuleTest.php
+++ b/tests/PHPStan/Rules/Arrays/NonexistentOffsetInArrayDimFetchRuleTest.php
@@ -772,13 +772,37 @@ public function testMixed(): void
 				'Cannot access offset 5 on T of mixed.',
 				11,
 			],
+			[
+				'Cannot access offset 5 on T of mixed.',
+				12,
+			],
+			[
+				'Cannot access offset 5 on T of mixed.',
+				18,
+			],
 			[
 				'Cannot access offset 5 on mixed.',
-				16,
+				24,
+			],
+			[
+				'Cannot access offset 5 on mixed.',
+				25,
+			],
+			[
+				'Cannot access offset 5 on mixed.',
+				31,
+			],
+			[
+				'Cannot access offset 5 on mixed.',
+				37,
+			],
+			[
+				'Cannot access offset 5 on mixed.',
+				38,
 			],
 			[
 				'Cannot access offset 5 on mixed.',
-				21,
+				44,
 			],
 		]);
 	}
diff --git a/tests/PHPStan/Rules/Arrays/data/offset-access-mixed.php b/tests/PHPStan/Rules/Arrays/data/offset-access-mixed.php
index 9f3300ce65..cea536bf60 100644
--- a/tests/PHPStan/Rules/Arrays/data/offset-access-mixed.php
+++ b/tests/PHPStan/Rules/Arrays/data/offset-access-mixed.php
@@ -9,14 +9,38 @@
 function foo(mixed $a): void
 {
 	var_dump($a[5]);
+	isset($a[5]); // error, because including object type
+
+	if (is_object($a)) {
+		throw new \Error();
+	}
+
+	var_dump($a[5]); // error
+	isset($a[5]); // ok, because object type, which throws an error do not implement ArrayAccess, is subtracted
 }
 
 function foo2(mixed $a): void
 {
 	var_dump($a[5]);
+	isset($a[5]);
+
+	if (is_object($a)) {
+		throw new \Error();
+	}
+
+	var_dump($a[5]); // error
+	isset($a[5]); // ok, because object type, which throws an error do not implement ArrayAccess, is subtracted
 }
 
 function foo3($a): void
 {
 	var_dump($a[5]);
+	isset($a[5]);
+
+	if (is_object($a)) {
+		throw new \Error();
+	}
+
+	var_dump($a[5]); // error
+	isset($a[5]); // ok, because object type, which throws an error do not implement ArrayAccess, is subtracted
 }