Part 4 of nullable and modernization

src/log4net.Tests/Appender/DebugAppenderTest.cs

@@ -139,17 +139,11 @@ public void MethodNameCategoryTest()
 
     private class TestErrorHandler : IErrorHandler
     {
-      private bool m_errorOccured = false;
+      public bool ErrorOccured { get; private set; }
 
-      public bool ErrorOccured
+      public void Error(string message, Exception? e, ErrorCode errorCode)
       {
-        get { return m_errorOccured; }
-      }
-      #region IErrorHandler Members
-
-      public void Error(string message, Exception e, ErrorCode errorCode)
-      {
-        m_errorOccured = true;
+        ErrorOccured = true;
       }
 
       public void Error(string message, Exception e)
@@ -161,8 +155,6 @@ public void Error(string message)
       {
         Error(message, null, ErrorCode.GenericFailure);
       }
-
-      #endregion
     }
   }
 }

src/log4net.Tests/Appender/RollingFileAppenderTest.cs

@@ -69,17 +69,17 @@ private sealed class SilentErrorHandler : IErrorHandler
 
       public void Error(string message)
       {
-        m_buffer.Append(message + "\n");
+        m_buffer.Append(message + '\n');
       }
 
       public void Error(string message, Exception e)
       {
-        m_buffer.Append(message + "\n" + e.Message + "\n");
+        m_buffer.Append(message + '\n' + e.Message + '\n');
       }
 
-      public void Error(string message, Exception e, ErrorCode errorCode)
+      public void Error(string message, Exception? e, ErrorCode errorCode)
       {
-        m_buffer.Append(message + "\n" + e.Message + "\n");
+        m_buffer.Append(message + '\n' + e?.Message + '\n');
       }
     }
 
@@ -1862,7 +1862,9 @@ private void VerifyInitializeRollBackups(int iBackups, int iMaxSizeRollBackups)
       string sBaseFile = "LogFile.log";
       var arrFiles = new List<string> { "junk1" };
       for (int i = 0; i < iBackups; i++)
+      {
         arrFiles.Add(MakeFileName(sBaseFile, i));
+      }
 
       RollingFileAppender rfa = new();
       rfa.RollingStyle = RollingFileAppender.RollingMode.Size;
@@ -1876,9 +1878,13 @@ private void VerifyInitializeRollBackups(int iBackups, int iMaxSizeRollBackups)
       // 2 = file.log.1
       // 3 = file.log.2
       if (iBackups is 0 or 1)
+      {
         Assert.AreEqual(0, rfa.CurrentSizeRollBackups);
+      }
       else
+      {
         Assert.AreEqual(Math.Min(iBackups - 1, iMaxSizeRollBackups), rfa.CurrentSizeRollBackups);
+      }
     }
 
     /// <summary>

src/log4net.Tests/Appender/SmtpPickupDirAppenderTest.cs

@@ -18,8 +18,6 @@
 #endregion
 
 using System;
-using System.Collections;
-using System.Diagnostics;
 using System.IO;
 using System.Text;
 
@@ -41,33 +39,31 @@ public class SmtpPickupDirAppenderTest
 
     private class SilentErrorHandler : IErrorHandler
     {
-      private StringBuilder m_buffer = new StringBuilder();
+      private readonly StringBuilder m_buffer = new();
 
-      public string Message
-      {
-        get { return m_buffer.ToString(); }
-      }
+      public string Message => m_buffer.ToString();
 
       public void Error(string message)
       {
-        m_buffer.Append(message + "\n");
+        m_buffer.Append(message + '\n');
       }
 
       public void Error(string message, Exception e)
       {
-        m_buffer.Append(message + "\n" + e.Message + "\n");
+        m_buffer.Append(message + '\n' + e.Message + '\n');
       }
 
       public void Error(string message, Exception e, ErrorCode errorCode)
       {
-        m_buffer.Append(message + "\n" + e.Message + "\n");
+        m_buffer.Append(message + '\n' + e.Message + '\n');
       }
     }
 
     public SmtpPickupDirAppenderTest()
     {
       _testPickupDir = Path.Combine(Directory.GetCurrentDirectory(), "SmtpPickupDirAppenderTest_PickupDir");
     }
+
     /// <summary>
     /// Sets up variables used for the tests
     /// </summary>
@@ -131,8 +127,7 @@ private ILogger CreateLogger(SmtpPickupDirAppender appender)
     {
       Repository.Hierarchy.Hierarchy h = (Repository.Hierarchy.Hierarchy)LogManager.CreateRepository("TestRepository");
 
-      PatternLayout layout = new PatternLayout();
-      layout.ConversionPattern = "%m%n";
+      var layout = new PatternLayout { ConversionPattern = "%m%n" };
       layout.ActivateOptions();
 
       appender.Layout = layout;
@@ -199,7 +194,7 @@ public void TestOutputContainsSentDate()
       }
       Assert.IsTrue(hasDateHeader, "Output must contains a date header");
 
-      Assert.AreEqual("", sh.Message, "Unexpected error message");
+      Assert.AreEqual(string.Empty, sh.Message, "Unexpected error message");
     }
 
     /// <summary>
@@ -220,7 +215,7 @@ public void TestConfigurableFileExtension()
       Assert.AreEqual(1, Directory.GetFiles(_testPickupDir).Length);
       FileInfo fileInfo = new FileInfo(Directory.GetFiles(_testPickupDir)[0]);
       Assert.AreEqual("." + fileExtension, fileInfo.Extension);
-      Assert.DoesNotThrow(delegate { new Guid(fileInfo.Name.Substring(0, fileInfo.Name.Length - fileInfo.Extension.Length)); }); // Assert that filename before extension is a guid
+      Assert.IsTrue(Guid.TryParse(fileInfo.Name.Substring(0, fileInfo.Name.Length - fileInfo.Extension.Length), out _));
 
       Assert.AreEqual("", sh.Message, "Unexpected error message");
     }
@@ -241,9 +236,9 @@ public void TestDefaultFileNameIsAGuid()
       Assert.AreEqual(1, Directory.GetFiles(_testPickupDir).Length);
       FileInfo fileInfo = new FileInfo(Directory.GetFiles(_testPickupDir)[0]);
       Assert.IsEmpty(fileInfo.Extension);
-      Assert.DoesNotThrow(delegate { new Guid(fileInfo.Name); }); // Assert that filename is a guid
+      Assert.IsTrue(Guid.TryParse(fileInfo.Name, out _));
 
-      Assert.AreEqual("", sh.Message, "Unexpected error message");
+      Assert.AreEqual(string.Empty, sh.Message, "Unexpected error message");
     }
   }
 }

src/log4net.Tests/DateFormatter/AbsoluteTimeDateFormatterTest.cs

@@ -18,88 +18,103 @@
 #endregion
 
 using System;
+using System.Globalization;
 using System.IO;
 using System.Text;
 using log4net.DateFormatter;
 using NUnit.Framework;
 
 namespace log4net.Tests.DateFormatter
 {
-
-    [TestFixture]
-    public class AbsoluteTimeDateFormatterTest
+  [TestFixture]
+  public class AbsoluteTimeDateFormatterTest
+  {
+    [TearDown]
+    public void ResetCounts()
     {
+      FormatterOne.Invocations = 0;
+    }
 
-        [TearDown]
-        public void resetCounts()
-        {
-            FormatterOne.invocations = 0;
-        }
-
-        [Test]
-        public void CacheWorksForSameTicks()
-        {
-            StringWriter sw = new StringWriter();
-            FormatterOne f1 = new FormatterOne();
-            FormatterOne f2 = new FormatterOne();
-            DateTime dt = DateTime.Now;
-            f1.FormatDate(dt, sw);
-            f2.FormatDate(dt, sw);
-            Assert.AreEqual(1, FormatterOne.invocations);
-        }
+    [Test]
+    public void CacheWorksForSameTicks()
+    {
+      StringWriter sw = new StringWriter();
+      FormatterOne f1 = new FormatterOne();
+      FormatterOne f2 = new FormatterOne();
+      DateTime dt = DateTime.Now;
+      f1.FormatDate(dt, sw);
+      f2.FormatDate(dt, sw);
+      Assert.AreEqual(1, FormatterOne.Invocations);
+    }
 
-        [Test]
-        public void CacheWorksForSameSecond()
-        {
-            StringWriter sw = new StringWriter();
-            FormatterOne f1 = new FormatterOne();
-            FormatterOne f2 = new FormatterOne();
-            DateTime dt1 = DateTime.Today;
-            DateTime dt2 = dt1.AddMilliseconds(600);
-            f1.FormatDate(dt1, sw);
-            f2.FormatDate(dt2, sw);
-            Assert.AreEqual(1, FormatterOne.invocations);
-        }
+    [Test]
+    public void CacheWorksForSameSecond()
+    {
+      StringWriter sw = new StringWriter();
+      FormatterOne f1 = new FormatterOne();
+      FormatterOne f2 = new FormatterOne();
+      DateTime dt1 = DateTime.Today;
+      DateTime dt2 = dt1.AddMilliseconds(600);
+      f1.FormatDate(dt1, sw);
+      f2.FormatDate(dt2, sw);
+      Assert.AreEqual(1, FormatterOne.Invocations);
+    }
 
-        [Test]
-        public void CacheExpiresWhenCrossingSecond()
-        {
-            StringWriter sw = new StringWriter();
-            FormatterOne f1 = new FormatterOne();
-            FormatterOne f2 = new FormatterOne();
-            DateTime dt1 = DateTime.Today.AddMinutes(1);
-            DateTime dt2 = dt1.AddMilliseconds(1100);
-            f1.FormatDate(dt1, sw);
-            f2.FormatDate(dt2, sw);
-            Assert.AreEqual(2, FormatterOne.invocations);
-        }
+    [Test]
+    public void CacheExpiresWhenCrossingSecond()
+    {
+      StringWriter sw = new StringWriter();
+      FormatterOne f1 = new FormatterOne();
+      FormatterOne f2 = new FormatterOne();
+      DateTime dt1 = DateTime.Today.AddMinutes(1);
+      DateTime dt2 = dt1.AddMilliseconds(1100);
+      f1.FormatDate(dt1, sw);
+      f2.FormatDate(dt2, sw);
+      Assert.AreEqual(2, FormatterOne.Invocations);
+    }
 
-        [Test]
-        public void CacheIsLocalToSubclass()
-        {
-            StringWriter sw = new StringWriter();
-            FormatterOne f1 = new FormatterOne();
-            FormatterTwo f2 = new FormatterTwo();
-            DateTime dt1 = DateTime.Today.AddMinutes(10);
-            f1.FormatDate(dt1, sw);
-            f2.FormatDate(dt1, sw);
-            Assert.AreEqual(2, FormatterOne.invocations);
-        }
+    [Test]
+    public void CacheIsLocalToSubclass()
+    {
+      StringWriter sw = new StringWriter();
+      FormatterOne f1 = new FormatterOne();
+      FormatterTwo f2 = new FormatterTwo();
+      DateTime dt1 = DateTime.Today.AddMinutes(10);
+      f1.FormatDate(dt1, sw);
+      f2.FormatDate(dt1, sw);
+      Assert.AreEqual(2, FormatterOne.Invocations);
     }
 
-    internal class FormatterOne : AbsoluteTimeDateFormatter
+    [Test]
+    public void TestFormattingResults()
     {
-        internal static int invocations = 0;
+      var formatter = new AbsoluteTimeDateFormatter();
+      var sb = new StringBuilder();
+      using var writer = new StringWriter(sb, CultureInfo.InvariantCulture);
 
-        override protected void FormatDateWithoutMillis(DateTime dateToFormat,
-                                                        StringBuilder buffer)
-        {
-            invocations++;
-        }
-
+      // Tests for prepended 0 characters for 2-digit and 3-digit portions.
+      formatter.FormatDate(new DateTime(1970, 1, 1, 1, 1, 1).AddMilliseconds(1), writer);
+      Assert.AreEqual("01:01:01,001", sb.ToString());
+      sb.Clear();
+
+      // Non-zero-prepend case.
+      formatter.FormatDate(new DateTime(2100, 12, 30, 11, 59, 59).AddMilliseconds(100), writer);
+      Assert.AreEqual("11:59:59,100", sb.ToString());
+      sb.Clear();
     }
+  }
+
+  internal class FormatterOne : AbsoluteTimeDateFormatter
+  {
+    internal static int Invocations;
 
-    internal class FormatterTwo : FormatterOne
+    override protected void FormatDateWithoutMillis(DateTime dateToFormat, StringBuilder buffer)
     {
+      Invocations++;
     }
+  }
+
+  internal class FormatterTwo : FormatterOne
+  {
+  }
 }

src/log4net.Tests/DateFormatter/DateTimeDateFormatterTest.cs

@@ -0,0 +1,59 @@
+#region Apache License
+//
+// Licensed to the Apache Software Foundation (ASF) under one or more 
+// contributor license agreements. See the NOTICE file distributed with
+// this work for additional information regarding copyright ownership. 
+// The ASF licenses this file to you under the Apache License, Version 2.0
+// (the "License"); you may not use this file except in compliance with 
+// the License. You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#endregion
+
+using System;
+using System.Globalization;
+using System.IO;
+using System.Text;
+using log4net.DateFormatter;
+using NUnit.Framework;
+
+namespace log4net.Tests.DateFormatter
+{
+  [TestFixture]
+  public class DateTimeDateFormatterTest
+  {
+    [Test]
+    public void TestFormattingResults()
+    {
+      var sb = new StringBuilder();
+      using var writer = new StringWriter(sb, CultureInfo.InvariantCulture);
+
+      // Tests for prepended 0 characters for 2-digit and 3-digit portions.
+      var formatter = new DateTimeDateFormatter();
+      formatter.FormatDate(new DateTime(1970, 1, 1, 1, 1, 1).AddMilliseconds(1), writer);
+      Assert.AreEqual("01 Jan 1970 01:01:01,001", sb.ToString());
+      sb.Clear();
+
+      // Non-zero-prepend case.
+      var formatter2 = new DifferentTypeNameDateTimeDateFormatter();
+      formatter2.FormatDate(new DateTime(2100, 12, 30, 11, 59, 59).AddMilliseconds(100), writer);
+      Assert.AreEqual("30 Dec 2100 11:59:59,100", sb.ToString());
+      sb.Clear();
+    }
+
+    /// <summary>
+    /// Internal caching of datetime strings is by datetime class name. Avoid waiting
+    /// by adding another type name.
+    /// </summary>
+    private sealed class DifferentTypeNameDateTimeDateFormatter : DateTimeDateFormatter
+    {
+    }
+  }
+}