Add more tests for CheckInteger

Tests/HelpersValidatorTest.cs

@@ -24,5 +24,25 @@ namespace Tests {
                 Assert.That(Validator.CheckInteger(CreateTextBox("4567"), false, 3).IsValid, Is.True);
             });
         }
+
+        [Test]
+        public void Test_CheckInteger_Caret() {
+            var tb = CreateTextBox("1a2b3c", 2);
+            Assert.Multiple(() => {
+                Assert.That(Validator.CheckInteger(tb, true).IsValid, Is.True);
+                Assert.That(tb.Text, Is.EqualTo("123"));
+                Assert.That(tb.CaretIndex, Is.EqualTo(1));
+            });
+        }
+
+        [Test]
+        public void Test_CheckInteger_MaxLen() {
+            var tb = CreateTextBox("1a2b3c4d5e", 4);
+            Assert.Multiple(() => {
+                Assert.That(Validator.CheckInteger(tb, true, 3).IsValid, Is.True);
+                Assert.That(tb.Text, Is.EqualTo("123"));
+                Assert.That(tb.CaretIndex, Is.EqualTo(2));
+            });
+        }
     }
 }