540 sftp does not download the file then errors

src/Directory.Build.props

@@ -1,14 +1,14 @@
 <Project>
   <PropertyGroup>
-    <Version>1.21.0.0</Version>
-    <AssemblyVersion>1.21.0.0</AssemblyVersion>
-    <FileVersion>1.21.0.0</FileVersion>
-    <InformationalVersion>1.20.0.0</InformationalVersion>
+    <Version>1.31.0.0</Version>
+    <AssemblyVersion>1.31.0.0</AssemblyVersion>
+    <FileVersion>1.31.0.0</FileVersion>
+    <InformationalVersion>1.31.0.0</InformationalVersion>
     <Authors>Hirogen, zarunbal, RandallFlagg, TheNicker</Authors>
-    <Company>Log Expert</Company>
+    <Company>LogExperts</Company>
     <ImplicitUsings>enable</ImplicitUsings>
     <Nullable>enable</Nullable>
-    <GenerateAssemblyInfo>false</GenerateAssemblyInfo>
+    <GenerateAssemblyInfo>true</GenerateAssemblyInfo>
     <AllowUnsafeBlocks>false</AllowUnsafeBlocks>
     <AssemblyOriginatorKeyFile>..\Solution Items\Key.snk</AssemblyOriginatorKeyFile>
     <PublishAot>false</PublishAot>
@@ -21,8 +21,8 @@
     <RepositoryUrl>https://github.com/LogExperts/LogExpert</RepositoryUrl>
     <PackageTags>LogExpert, Columnizer, Logging, Windows, Winforms</PackageTags>
     <RepositoryType>git</RepositoryType>
-    <PackageReleaseNotes>https://github.com/LogExperts/LogExpert/releases/tag/v.1.20.0</PackageReleaseNotes>
-    <PackageVersion>1.21.0.0</PackageVersion>
+    <PackageReleaseNotes>https://github.com/LogExperts/LogExpert/releases/tag/v.1.31.0</PackageReleaseNotes>
+    <PackageVersion>1.31.0.0</PackageVersion>
     <Optimize Condition="'$(Configuration)' == 'Release'">true</Optimize>
     <Product>LogExpert</Product>
     <Copyright>Copyright © LogExpert 2025</Copyright>

src/LogExpert.Core/Classes/Log/RolloverFilenameHandler.cs

@@ -52,10 +52,13 @@ public RolloverFilenameHandler(ILogFileInfo logFileInfo, MultiFileOptions option
     public LinkedList<string> GetNameList(IPluginRegistry pluginRegistry)
     {
         LinkedList<string> fileList = new();
+
         var fileName = _filenameBuilder.BuildFileName();
         var filePath = _logFileInfo.DirectoryName + _logFileInfo.DirectorySeparatorChar + fileName;
-        fileList.AddFirst(filePath);
+        _ = fileList.AddFirst(filePath);
+
         var found = true;
+
         while (found)
         {
             found = false;
@@ -67,11 +70,12 @@ public LinkedList<string> GetNameList(IPluginRegistry pluginRegistry)
                 filePath = _logFileInfo.DirectoryName + _logFileInfo.DirectorySeparatorChar + fileName;//TODO: Change to Directory.Combine
                 if (FileExists(filePath, pluginRegistry))
                 {
-                    fileList.AddFirst(filePath);
+                    _ = fileList.AddFirst(filePath);
                     found = true;
                     continue;
                 }
             }
+
             // if file with index isn't found or no index is in format pattern, decrement the current date
             if (_filenameBuilder.IsDatePattern)
             {
@@ -84,7 +88,7 @@ public LinkedList<string> GetNameList(IPluginRegistry pluginRegistry)
                     filePath = _logFileInfo.DirectoryName + _logFileInfo.DirectorySeparatorChar + fileName;//TODO: Change to Directory.Combine
                     if (FileExists(filePath, pluginRegistry))
                     {
-                        fileList.AddFirst(filePath);
+                        _ = fileList.AddFirst(filePath);
                         found = true;
                         break;
                     }
@@ -104,8 +108,14 @@ public LinkedList<string> GetNameList(IPluginRegistry pluginRegistry)
     private bool FileExists(string filePath, IPluginRegistry pluginRegistry)
     {
         var fs = pluginRegistry.FindFileSystemForUri(filePath);
+
+        if(fs == null)
+        {
+            return false; 
+        }
+
         var info = fs.GetLogfileInfo(filePath);
-        return info.FileExists;
+        return info is not null && info.FileExists;
     }
 
     #endregion

src/LogExpert.Resources/Resources.de.resx

@@ -2134,18 +2134,18 @@ LogExpert neu starten, um die Änderungen zu übernehmen?</value>
     <value>TabController ist bereits mit einem DockPanel initialisiert</value>
   </data>
   <data name="SettingsDialog_UI_PortableMode_Title" xml:space="preserve">
-    <value>Tragbarer Modus</value>
+    <value>Portable Modus</value>
   </data>
   <data name="SettingsDialog_UI_PortableMode_CopySettingsQuestion" xml:space="preserve">
-    <value>Der tragbare Modus konnte nicht aktiviert werden: {0}</value>
+    <value>Möchten Sie Ihre aktuellen Einstellungen in den Portable-Modus Konfigurationsordner kopieren?</value>
   </data>
   <data name="SettingsDialog_UI_PortableMode_MoveSettingsQuestion" xml:space="preserve">
-    <value>Möchten Sie Ihre aktuellen Einstellungen in den tragbaren Konfigurationsordner kopieren?</value>
+    <value>Möchten Sie die tragbaren Einstellungen zurück in den Standardkonfigurationsordner (%APPDATA%\LogExpert) verschieben?</value>
   </data>
   <data name="SettingsDialog_UI_PortableMode_ActivationError" xml:space="preserve">
-    <value>Einige Dateien konnten nicht migriert werden: {0}</value>
+    <value>Der Portable Modus konnte nicht aktiviert werden: {0}</value>
   </data>
   <data name="SettingsDialog_UI_PortableMode_MigrationError" xml:space="preserve">
-    <value>Möchten Sie die tragbaren Einstellungen zurück in den Standardkonfigurationsordner (%APPDATA%\LogExpert) verschieben?</value>
+    <value>Einige Dateien konnten nicht migriert werden: {0}</value>
   </data>
 </root>

src/LogExpert.Resources/Resources.resx

@@ -2146,15 +2146,15 @@ Restart LogExpert to apply changes?</value>
     <value>Portable Mode</value>
   </data>
   <data name="SettingsDialog_UI_PortableMode_CopySettingsQuestion" xml:space="preserve">
-    <value>Failed to activate portable mode: {0}</value>
+    <value>Do you want to copy your current settings to the portable configuration folder?</value>
   </data>
   <data name="SettingsDialog_UI_PortableMode_MoveSettingsQuestion" xml:space="preserve">
-    <value>Do you want to copy your current settings to the portable configuration folder?</value>
+    <value>Do you want to move the portable settings back to the default configuration folder (%APPDATA%\LogExpert)?</value>
   </data>
   <data name="SettingsDialog_UI_PortableMode_ActivationError" xml:space="preserve">
-    <value>Some files could not be migrated: {0}</value>
+    <value>Failed to activate portable mode: {0}</value>
   </data>
   <data name="SettingsDialog_UI_PortableMode_MigrationError" xml:space="preserve">
-    <value>Do you want to move the portable settings back to the default configuration folder (%APPDATA%\LogExpert)?</value>
+    <value>Some files could not be migrated: {0}</value>
   </data>
 </root>

src/LogExpert.Resources/Resources.zh-CN.resx

@@ -2054,15 +2054,15 @@ YY[YY] = 年
     <value>便携模式</value>
   </data>
   <data name="SettingsDialog_UI_PortableMode_CopySettingsQuestion" xml:space="preserve">
-    <value>无法激活便携模式：{0}</value>
+    <value>您想将当前设置复制到便携式配置文件夹吗？</value>
   </data>
   <data name="SettingsDialog_UI_PortableMode_MoveSettingsQuestion" xml:space="preserve">
-    <value>您想将当前设置复制到便携式配置文件夹吗？</value>
+    <value>您想要将可移植设置移回默认配置文件夹 (%APPDATA%\LogExpert) 吗？</value>
   </data>
   <data name="SettingsDialog_UI_PortableMode_ActivationError" xml:space="preserve">
-    <value>某些文件无法迁移：{0}</value>
+    <value>无法激活便携模式：{0}</value>
   </data>
   <data name="SettingsDialog_UI_PortableMode_MigrationError" xml:space="preserve">
-    <value>您想要将可移植设置移回默认配置文件夹 (%APPDATA%\LogExpert) 吗？</value>
+    <value>某些文件无法迁移：{0}</value>
   </data>
 </root>

src/LogExpert.Tests/RolloverFilenameHandlerNullTests.cs

@@ -0,0 +1,136 @@
+using ColumnizerLib;
+
+using LogExpert.Core.Classes.Log;
+using LogExpert.Core.Entities;
+using LogExpert.Core.Interface;
+
+using Moq;
+
+using NUnit.Framework;
+
+namespace LogExpert.Tests;
+
+[TestFixture]
+internal class RolloverFilenameHandlerNullTests
+{
+    /// <summary>
+    /// Verifies that GetNameList does not throw when GetLogfileInfo returns null
+    /// for rollover file candidates. This simulates the SFTP scenario where
+    /// constructing SftpLogFileInfo fails for non-existent files.
+    /// </summary>
+    [Test]
+    public void GetNameList_WhenGetLogfileInfoReturnsNull_DoesNotThrow ()
+    {
+        // Arrange: Create a mock ILogFileInfo for the "base" file
+        var baseFileInfo = new Mock<ILogFileInfo>();
+        _ = baseFileInfo.Setup(f => f.FileName).Returns("app.log");
+        _ = baseFileInfo.Setup(f => f.DirectoryName).Returns("sftp://host/var/log");
+        _ = baseFileInfo.Setup(f => f.DirectorySeparatorChar).Returns('/');
+        _ = baseFileInfo.Setup(f => f.FileExists).Returns(true);
+
+        // Arrange: Create a mock IFileSystemPlugin that returns null for rollover files
+        var mockFs = new Mock<IFileSystemPlugin>();
+        _ = mockFs.Setup(fs => fs.CanHandleUri(It.IsAny<string>())).Returns(true);
+        // Return null for any GetLogfileInfo call — simulates constructor failure
+        _ = mockFs.Setup(fs => fs.GetLogfileInfo(It.IsAny<string>())).Returns((ILogFileInfo)null);
+
+        // Arrange: Create a mock IPluginRegistry
+        var mockRegistry = new Mock<IPluginRegistry>();
+        _ = mockRegistry.Setup(r => r.FindFileSystemForUri(It.IsAny<string>())).Returns(mockFs.Object);
+
+        MultiFileOptions options = new()
+        {
+            FormatPattern = "*$J(.)",
+            MaxDayTry = 5
+        };
+
+        RolloverFilenameHandler handler = new(baseFileInfo.Object, options);
+
+        // Act & Assert: Should not throw NullReferenceException
+        LinkedList<string> result = null;
+        Assert.DoesNotThrow(() => result = handler.GetNameList(mockRegistry.Object));
+
+        // The list should contain only the base file
+        Assert.That(result, Is.Not.Null);
+        Assert.That(result.Count, Is.EqualTo(1));
+        Assert.That(result.First.Value, Does.Contain("app.log"));
+    }
+
+    /// <summary>
+    /// Verifies that GetNameList does not throw when FindFileSystemForUri returns null.
+    /// This could happen with an unrecognized URI scheme.
+    /// </summary>
+    [Test]
+    public void GetNameList_WhenFindFileSystemReturnsNull_DoesNotThrow ()
+    {
+        // Arrange
+        var baseFileInfo = new Mock<ILogFileInfo>();
+        _ = baseFileInfo.Setup(f => f.FileName).Returns("app.log");
+        _ = baseFileInfo.Setup(f => f.DirectoryName).Returns("custom://host/logs");
+        _ = baseFileInfo.Setup(f => f.DirectorySeparatorChar).Returns('/');
+        _ = baseFileInfo.Setup(f => f.FileExists).Returns(true);
+
+        var mockRegistry = new Mock<IPluginRegistry>();
+        _ = mockRegistry.Setup(r => r.FindFileSystemForUri(It.IsAny<string>())).Returns((IFileSystemPlugin)null);
+
+        MultiFileOptions options = new()
+        {
+            FormatPattern = "*$J(.)",
+            MaxDayTry = 3
+        };
+
+        RolloverFilenameHandler handler = new(baseFileInfo.Object, options);
+
+        // Act & Assert
+        LinkedList<string> result = null;
+        Assert.DoesNotThrow(() => result = handler.GetNameList(mockRegistry.Object));
+
+        Assert.That(result, Is.Not.Null);
+        Assert.That(result.Count, Is.EqualTo(1));
+    }
+
+    /// <summary>
+    /// Verifies that GetNameList correctly finds rollover files when GetLogfileInfo
+    /// returns a valid ILogFileInfo with FileExists = true. Ensures the null guard
+    /// does not break the normal happy path.
+    /// </summary>
+    [Test]
+    public void GetNameList_WhenRolloverFilesExist_ReturnsAllFiles ()
+    {
+        // Arrange: base file
+        var baseFileInfo = new Mock<ILogFileInfo>();
+        _ = baseFileInfo.Setup(f => f.FileName).Returns("app.log");
+        _ = baseFileInfo.Setup(f => f.DirectoryName).Returns("/var/log");
+        _ = baseFileInfo.Setup(f => f.DirectorySeparatorChar).Returns('/');
+
+        // Arrange: rollover file .log.1 exists, .log.2 does not
+        var rollover1Info = new Mock<ILogFileInfo>();
+        _ = rollover1Info.Setup(f => f.FileExists).Returns(true);
+
+        var mockFs = new Mock<IFileSystemPlugin>();
+        _ = mockFs.Setup(fs => fs.CanHandleUri(It.IsAny<string>())).Returns(true);
+
+        // First call (for .log.1) returns a file that exists
+        // Second call (for .log.2) returns null (simulating constructor failure)
+        _ = mockFs.SetupSequence(fs => fs.GetLogfileInfo(It.IsAny<string>()))
+            .Returns(rollover1Info.Object)
+            .Returns((ILogFileInfo)null);
+
+        var mockRegistry = new Mock<IPluginRegistry>();
+        _ = mockRegistry.Setup(r => r.FindFileSystemForUri(It.IsAny<string>())).Returns(mockFs.Object);
+
+        MultiFileOptions options = new()
+        {
+            FormatPattern = "*$J(.)",
+            MaxDayTry = 3
+        };
+
+        RolloverFilenameHandler handler = new(baseFileInfo.Object, options);
+
+        // Act
+        var result = handler.GetNameList(mockRegistry.Object);
+
+        // Assert: base file + 1 rollover file
+        Assert.That(result.Count, Is.EqualTo(2));
+    }
+}

src/LogExpert.UI/Controls/LogWindow/LogWindow.cs

@@ -6302,7 +6302,7 @@ public PersistenceData GetPersistenceData ()
             TabName = Text,
             SessionFileName = SessionFileName,
             Columnizer = CurrentColumnizer,
-            LineCount = _logFileReader.LineCount
+            LineCount = _logFileReader != null ? _logFileReader.LineCount : 0
 
 
         };

src/LogExpert.UI/Dialogs/SettingsDialog.cs

@@ -923,7 +923,8 @@ private void OnPortableModeCheckedChanged (object sender, EventArgs e)
                             var markerPath = Path.Join(ConfigManager.PortableConfigDir, ConfigManager.PortableModeSettingsFileName);
                             if (!File.Exists(markerPath))
                             {
-                                using (File.Create(markerPath)) { }
+                                using (File.Create(markerPath)) 
+                                { }   
                             }
 
                             Preferences.PortableMode = true;