Making Culture Invariant When Validating Date to negate deferent form…

…ats (#17257)

* CultureInfo.InvariantCulture,

* adding unitTests by @Matthew-Wise

src/Umbraco.Core/PropertyEditors/Validators/DateTimeValidator.cs

@@ -1,4 +1,5 @@
 using System.ComponentModel.DataAnnotations;
+using System.Globalization;
 using Umbraco.Extensions;
 
 namespace Umbraco.Cms.Core.PropertyEditors.Validators;
@@ -16,7 +17,7 @@ public IEnumerable<ValidationResult> Validate(object? value, string? valueType,
             yield break;
         }
 
-        if (DateTime.TryParse(value.ToString(), out DateTime dt) == false)
+        if (DateTime.TryParse(value.ToString(), CultureInfo.InvariantCulture, out DateTime dt) == false)
         {
             yield return new ValidationResult(
                 string.Format("The string value {0} cannot be parsed into a DateTime", value),

tests/Umbraco.Tests.UnitTests/Umbraco.Core/PropertyEditors/Validators/DateTimeValidatorTests.cs

@@ -0,0 +1,29 @@
+using System.Globalization;
+using NUnit.Framework;
+using Umbraco.Cms.Core.PropertyEditors.Validators;
+
+namespace Umbraco.Cms.Tests.UnitTests.Umbraco.Core.PropertyEditors.Validators;
+
+[TestFixture]
+public class DateTimeValidatorTests
+{
+    [TestCase("en-US", "yyyy-MM-dd HH:mm:ss", TestName = "US Thread, DateTimeValidator")]
+    [TestCase("en-US", "dd-MM-yyyy HH:mm:ss", TestName = "US Thread, DateTimeValidator ar-SA format")]
+    [TestCase("ar-SA", "dd-MM-yyyy HH:mm:ss", TestName = "Arabian Saudi Thread, DateTimeValidator")]
+    [TestCase("ar-SA", "yyyy-MM-dd HH:mm:ss", TestName = "Arabian Saudi Thread, DateTimeValidator US format")]
+    public void DateTimeValidatorIsCultureInvariant(string culture, string format)
+    {
+        var dateString = DateTime.Now.ToString(format);
+
+        var cultureInfo = new CultureInfo(culture);
+        Thread.CurrentThread.CurrentCulture = cultureInfo;
+        Thread.CurrentThread.CurrentUICulture = cultureInfo;
+
+        var validator = new DateTimeValidator();
+        var validationResults = validator.Validate(dateString, "DATETIME", new Dictionary<string, object>
+        {
+            ["format"] = format
+        });
+        CollectionAssert.IsEmpty(validationResults);
+    }
+}