diff --git a/src/libraries/System.ServiceModel.Syndication/tests/System.ServiceModel.Syndication.Tests.csproj b/src/libraries/System.ServiceModel.Syndication/tests/System.ServiceModel.Syndication.Tests.csproj
index 1d2c8ab02e08a9..df1cce5db2c3fb 100644
--- a/src/libraries/System.ServiceModel.Syndication/tests/System.ServiceModel.Syndication.Tests.csproj
+++ b/src/libraries/System.ServiceModel.Syndication/tests/System.ServiceModel.Syndication.Tests.csproj
@@ -11,6 +11,7 @@
+
diff --git a/src/libraries/System.ServiceModel.Syndication/tests/System/ServiceModel/Syndication/Rfc822DateParsingTests.cs b/src/libraries/System.ServiceModel.Syndication/tests/System/ServiceModel/Syndication/Rfc822DateParsingTests.cs
new file mode 100644
index 00000000000000..4064c35a8916e4
--- /dev/null
+++ b/src/libraries/System.ServiceModel.Syndication/tests/System/ServiceModel/Syndication/Rfc822DateParsingTests.cs
@@ -0,0 +1,82 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+using System.IO;
+using System.Xml;
+using Xunit;
+using System.Globalization;
+
+namespace System.ServiceModel.Syndication.Tests
+{
+ public class Rfc822DateParsingTests
+ {
+ [SkipOnTargetFramework(TargetFrameworkMonikers.NetFramework)] // NetFx requires double digit dates and four digit years
+ [Theory]
+ [InlineData("Mon, 2 Jun 2003 09:39:21 GMT", 2003, 6, 2, 9, 39, 21)]
+ [InlineData("2 Jun 2003 09:39:21 GMT", 2003, 6, 2, 9, 39, 21)]
+ [InlineData("02 Jun 03 09:39:21 GMT", 2003, 6, 2, 9, 39, 21)]
+ [InlineData("Mon, 2 Jun 03 09:39:21 GMT", 2003, 6, 2, 9, 39, 21)]
+ [InlineData("2 Jun 03 09:39 GMT", 2003, 6, 2, 9, 39, 0)]
+ [InlineData("02 Jun 03 09:39 GMT", 2003, 6, 2, 9, 39, 0)]
+ [InlineData("Mon, 2 Jun 03 09:39 GMT", 2003, 6, 2, 9, 39, 0)]
+ [InlineData("Mon, 02 Jun 03 09:39 GMT", 2003, 6, 2, 9, 39, 0)]
+ public void Rss20ItemFormatter_Read_SingleDigitDay_And_TwoDigitYear(string pubDate, int year, int month, int day, int hour, int minute, int second)
+ {
+ string xml = $"- {pubDate}
";
+ using var stringReader = new StringReader(xml);
+ using var reader = XmlReader.Create(stringReader);
+ var formatter = new Rss20ItemFormatter();
+ formatter.ReadFrom(reader);
+ DateTimeOffset expected = new DateTimeOffset(year, month, day, hour, minute, second, TimeSpan.Zero);
+ Assert.Equal(expected, formatter.Item.PublishDate);
+ }
+
+ [SkipOnTargetFramework(TargetFrameworkMonikers.NetFramework)] // NetFx requires double digit dates and four digit years
+ [Theory]
+ [InlineData("Mon, 02 Jun 03 09:39:21 +0000", 2003, 6, 2, 9, 39, 21)]
+ [InlineData("Mon, 02 Jun 03 09:39:21 -0000", 2003, 6, 2, 9, 39, 21)]
+ [InlineData("Mon, 02 Jun 03 09:39:21 UT", 2003, 6, 2, 9, 39, 21)]
+ public void Rss20ItemFormatter_Read_SingleDigitDay_NormalizedTimeZones(string pubDate, int year, int month, int day, int hour, int minute, int second)
+ {
+ string xml = $"- {pubDate}
";
+ using var stringReader = new StringReader(xml);
+ using var reader = XmlReader.Create(stringReader);
+ var formatter = new Rss20ItemFormatter();
+ formatter.ReadFrom(reader);
+ DateTimeOffset expectedUtc = new DateTimeOffset(year, month, day, hour, minute, second, TimeSpan.Zero);
+ Assert.Equal(expectedUtc, formatter.Item.PublishDate);
+ }
+
+ [SkipOnTargetFramework(TargetFrameworkMonikers.NetFramework)] // NetFx requires double digit dates and four digit years
+ [Theory]
+ [InlineData("2 Jun {year} 09:39 GMT", 6, 2, 9, 39, 0)]
+ [InlineData("02 Jun {year} 09:39:21 +0000", 6, 2, 9, 39, 21)]
+ [InlineData("02 Jun {year} 09:39:21 -0000", 6, 2, 9, 39, 21)]
+ [InlineData("02 Jun {year} 09:39:21 UT", 6, 2, 9, 39, 21)]
+ public void Rss20ItemFormatter_Read_SingleDigitDay_And_TwoDigitYear_Max(string pubDate, int month, int day, int hour, int minute, int second)
+ {
+ // As of .Net 8.0, CultureInfo.CurrentCulture.DateTimeFormat.Calendar.TwoDigitYearMax is 2049 for invariant and en-US cultures
+ var maxDate = CultureInfo.CurrentCulture.DateTimeFormat.Calendar.TwoDigitYearMax % 100;
+
+ // Test under/at the 2-digit year max threshold
+ var underDate = pubDate.Replace("{year}", maxDate.ToString());
+ string xml = $"- {underDate}
";
+ using var stringReader = new StringReader(xml);
+ using var reader = XmlReader.Create(stringReader);
+ var formatter = new Rss20ItemFormatter();
+ formatter.ReadFrom(reader);
+ DateTimeOffset expectedUnder = new DateTimeOffset(2000 + maxDate, month, day, hour, minute, second, TimeSpan.Zero);
+ Assert.Equal(expectedUnder, formatter.Item.PublishDate);
+
+ // Test over the 2-digit year max threshold
+ var overDate = pubDate.Replace("{year}", (maxDate + 1).ToString());
+ xml = $"- {overDate}
";
+ using var stringReaderOver = new StringReader(xml);
+ using var readerOver = XmlReader.Create(stringReaderOver);
+ formatter = new Rss20ItemFormatter();
+ formatter.ReadFrom(readerOver);
+ DateTimeOffset expectedOver = new DateTimeOffset(1900 + maxDate + 1, month, day, hour, minute, second, TimeSpan.Zero);
+ Assert.Equal(expectedOver, formatter.Item.PublishDate);
+ }
+ }
+}