Add support for creating and editing solution filter (.slnf) files from the CLI

src/Cli/dotnet/Commands/Build/BuildCommand.cs

@@ -13,7 +13,7 @@ public static class BuildCommand
 {
     public static CommandBase FromArgs(string[] args, string? msbuildPath = null)
     {
-        var parseResult = Parser.Parse(["dotnet", "build", ..args]);
+        var parseResult = Parser.Parse(["dotnet", "build", .. args]);
         return FromParseResult(parseResult, msbuildPath);
     }
 

src/Cli/dotnet/Commands/Clean/CleanCommand.cs

@@ -13,7 +13,7 @@ public class CleanCommand(MSBuildArgs msbuildArgs, string? msbuildPath = null) :
 {
     public static CommandBase FromArgs(string[] args, string? msbuildPath = null)
     {
-        var result = Parser.Parse(["dotnet", "clean", ..args]);
+        var result = Parser.Parse(["dotnet", "clean", .. args]);
         return FromParseResult(result, msbuildPath);
     }
 

src/Cli/dotnet/Commands/CliCommandStrings.resx

@@ -2630,6 +2630,9 @@ Proceed?</value>
     <value>Received 'ExecutionId' of value '{0}' for message '{1}' while the 'ExecutionId' received of the handshake message was '{2}'.</value>
     <comment>{Locked="ExecutionId"}</comment>
   </data>
+  <data name="SolutionFilterDoesNotSupportFolderOptions" xml:space="preserve">
+    <value>Solution filter files (.slnf) do not support the --in-root or --solution-folder options.</value>
+  </data>
   <data name="ErrorColon" xml:space="preserve">
     <value>error:</value>
   </data>

src/Cli/dotnet/Commands/Format/FormatCommand.cs

@@ -13,7 +13,7 @@ public class FormatCommand(IEnumerable<string> argsToForward) : FormatForwarding
 {
     public static FormatCommand FromArgs(string[] args)
     {
-        var result = Parser.Parse(["dotnet", "format", ..args]);
+        var result = Parser.Parse(["dotnet", "format", .. args]);
         return FromParseResult(result);
     }
 

src/Cli/dotnet/Commands/Hidden/Complete/CompleteCommand.cs

@@ -19,7 +19,7 @@ public static int Run(ParseResult parseResult)
 
     public static int RunWithReporter(string[] args, IReporter reporter)
     {
-        var result = Parser.Parse(["dotnet", "complete", ..args]);
+        var result = Parser.Parse(["dotnet", "complete", .. args]);
         return RunWithReporter(result, reporter);
     }
 

src/Cli/dotnet/Commands/Hidden/InternalReportInstallSuccess/InternalReportInstallSuccessCommand.cs

@@ -26,7 +26,7 @@ public static int Run(ParseResult parseResult)
 
     public static void ProcessInputAndSendTelemetry(string[] args, ITelemetry telemetry)
     {
-        var result = Parser.Parse(["dotnet", "internal-reportinstallsuccess", ..args]);
+        var result = Parser.Parse(["dotnet", "internal-reportinstallsuccess", .. args]);
         ProcessInputAndSendTelemetry(result, telemetry);
     }
 

src/Cli/dotnet/Commands/MSBuild/MSBuildCommand.cs

@@ -25,7 +25,7 @@ public class MSBuildCommand(
 {
     public static MSBuildCommand FromArgs(string[] args, string? msbuildPath = null)
     {
-        var result = Parser.Parse(["dotnet", "msbuild", ..args]);
+        var result = Parser.Parse(["dotnet", "msbuild", .. args]);
         return FromParseResult(result, msbuildPath);
     }
 

src/Cli/dotnet/Commands/Pack/PackCommand.cs

@@ -25,7 +25,7 @@ public class PackCommand(
 {
     public static CommandBase FromArgs(string[] args, string? msbuildPath = null)
     {
-        var parseResult = Parser.Parse(["dotnet", "pack", ..args]);
+        var parseResult = Parser.Parse(["dotnet", "pack", .. args]);
         return FromParseResult(parseResult, msbuildPath);
     }
 
@@ -94,14 +94,14 @@ public static int RunPackCommand(ParseResult parseResult)
 
         if (args.Count != 1)
         {
-            Console.Error.WriteLine(CliStrings.PackCmd_OneNuspecAllowed); 
+            Console.Error.WriteLine(CliStrings.PackCmd_OneNuspecAllowed);
             return 1;
         }
 
         var nuspecPath = args[0];
 
         var packArgs = new PackArgs()
-        { 
+        {
             Logger = new NuGetConsoleLogger(),
             Exclude = new List<string>(),
             OutputDirectory = parseResult.GetValue(PackCommandDefinition.OutputOption),

src/Cli/dotnet/Commands/Package/List/PackageListCommand.cs

@@ -4,13 +4,13 @@
 #nullable disable
 
 using System.CommandLine;
+using System.Globalization;
 using Microsoft.DotNet.Cli.Commands.Hidden.List;
+using Microsoft.DotNet.Cli.Commands.MSBuild;
 using Microsoft.DotNet.Cli.Commands.NuGet;
 using Microsoft.DotNet.Cli.CommandLine;
 using Microsoft.DotNet.Cli.Extensions;
 using Microsoft.DotNet.Cli.Utils;
-using System.Globalization;
-using Microsoft.DotNet.Cli.Commands.MSBuild;
 
 namespace Microsoft.DotNet.Cli.Commands.Package.List;
 

src/Cli/dotnet/Commands/Package/Search/PackageSearchCommand.cs

@@ -3,9 +3,10 @@
 
 #nullable disable
 
+using System.CommandLine;
 using Microsoft.DotNet.Cli.Commands.NuGet;
 using Microsoft.DotNet.Cli.CommandLine;
-using System.CommandLine;
+using Microsoft.DotNet.Cli.Extensions;
 
 namespace Microsoft.DotNet.Cli.Commands.Package.Search;
 

src/Cli/dotnet/Commands/Publish/PublishCommand.cs

@@ -22,7 +22,7 @@ private PublishCommand(
 
     public static CommandBase FromArgs(string[] args, string? msbuildPath = null)
     {
-        var parseResult = Parser.Parse(["dotnet", "publish", ..args]);
+        var parseResult = Parser.Parse(["dotnet", "publish", .. args]);
         return FromParseResult(parseResult);
     }
 

src/Cli/dotnet/Commands/Restore/RestoreCommand.cs

@@ -13,7 +13,7 @@ public static class RestoreCommand
 {
     public static CommandBase FromArgs(string[] args, string? msbuildPath = null)
     {
-        var result = Parser.Parse(["dotnet", "restore", ..args]);
+        var result = Parser.Parse(["dotnet", "restore", .. args]);
         return FromParseResult(result, msbuildPath);
     }
 

src/Cli/dotnet/Commands/Restore/RestoringCommand.cs

@@ -37,7 +37,7 @@ public RestoringCommand(
         string? msbuildPath = null,
         string? userProfileDir = null,
         bool? advertiseWorkloadUpdates = null)
-        : base(GetCommandArguments(msbuildArgs, noRestore),  msbuildPath)
+        : base(GetCommandArguments(msbuildArgs, noRestore), msbuildPath)
     {
         userProfileDir = CliFolderPathCalculator.DotnetUserProfileFolderPath;
         Task.Run(() => WorkloadManifestUpdater.BackgroundUpdateAdvertisingManifestsAsync(userProfileDir));
@@ -118,13 +118,13 @@ private static MSBuildArgs GetCommandArguments(
         ReadOnlyDictionary<string, string> restoreProperties =
             msbuildArgs.GlobalProperties?
             .Where(kvp => !IsPropertyExcludedFromRestore(kvp.Key))?
-            .ToDictionary(kvp => kvp.Key, kvp => kvp.Value, StringComparer.OrdinalIgnoreCase) is { } filteredList ? new(filteredList): ReadOnlyDictionary<string, string>.Empty;
+            .ToDictionary(kvp => kvp.Key, kvp => kvp.Value, StringComparer.OrdinalIgnoreCase) is { } filteredList ? new(filteredList) : ReadOnlyDictionary<string, string>.Empty;
         var restoreMSBuildArgs =
             MSBuildArgs.FromProperties(RestoreOptimizationProperties)
                        .CloneWithAdditionalTargets("Restore")
                        .CloneWithExplicitArgs([.. newArgumentsToAdd, .. existingArgumentsToForward])
                        .CloneWithAdditionalProperties(restoreProperties);
-        if (msbuildArgs.Verbosity is {} verbosity)
+        if (msbuildArgs.Verbosity is { } verbosity)
         {
             restoreMSBuildArgs = restoreMSBuildArgs.CloneWithVerbosity(verbosity);
         }
@@ -171,7 +171,7 @@ private static bool HasPropertyToExcludeFromRestore(MSBuildArgs msbuildArgs)
 
     private static readonly List<string> FlagsThatTriggerSilentSeparateRestore = [.. ComputeFlags(FlagsThatTriggerSilentRestore)];
 
-    private static readonly List<string> PropertiesToExcludeFromSeparateRestore = [ .. PropertiesToExcludeFromRestore ];
+    private static readonly List<string> PropertiesToExcludeFromSeparateRestore = [.. PropertiesToExcludeFromRestore];
 
     /// <summary>
     /// We investigate the arguments we're about to send to a separate restore call and filter out

src/Cli/dotnet/Commands/Solution/Add/SolutionAddCommand.cs

@@ -45,7 +45,7 @@ public SolutionAddCommand(ParseResult parseResult) : base(parseResult)
         _solutionFolderPath = parseResult.GetValue(SolutionAddCommandDefinition.SolutionFolderOption);
         _includeReferences = parseResult.GetValue(SolutionAddCommandDefinition.IncludeReferencesOption);
         SolutionArgumentValidator.ParseAndValidateArguments(_fileOrDirectory, _projects, SolutionArgumentValidator.CommandType.Add, _inRoot, _solutionFolderPath);
-        _solutionFileFullPath = SlnFileFactory.GetSolutionFileFullPath(_fileOrDirectory);
+        _solutionFileFullPath = SlnFileFactory.GetSolutionFileFullPath(_fileOrDirectory, includeSolutionFilterFiles: true);
     }
 
     public override int Execute()
@@ -58,14 +58,22 @@ public override int Execute()
         // Get project paths from the command line arguments
         PathUtility.EnsureAllPathsExist(_projects, CliStrings.CouldNotFindProjectOrDirectory, true);
 
-        IEnumerable<string> fullProjectPaths = _projects.Select(project =>
+        List<string> fullProjectPaths = _projects.Select(project =>
         {
             var fullPath = Path.GetFullPath(project);
             return Directory.Exists(fullPath) ? MsbuildProject.GetProjectFileFromDirectory(fullPath) : fullPath;
-        });
+        }).ToList();
 
-        // Add projects to the solution
-        AddProjectsToSolutionAsync(fullProjectPaths, CancellationToken.None).GetAwaiter().GetResult();
+        // Check if we're working with a solution filter file
+        if (_solutionFileFullPath.HasExtension(SlnfFileHelper.SlnfExtension))
+        {
+            AddProjectsToSolutionFilter(fullProjectPaths);
+        }
+        else
+        {
+            // Add projects to the solution
+            AddProjectsToSolutionAsync(fullProjectPaths, CancellationToken.None).GetAwaiter().GetResult();
+        }
         return 0;
     }
 
@@ -224,4 +232,68 @@ private void AddProject(SolutionModel solution, string fullProjectPath, ISolutio
             }
         }
     }
+
+    private void AddProjectsToSolutionFilter(IEnumerable<string> projectPaths)
+    {
+        // Solution filter files don't support --in-root or --solution-folder options
+        if (_inRoot || !string.IsNullOrEmpty(_solutionFolderPath))
+        {
+            throw new GracefulException(CliCommandStrings.SolutionFilterDoesNotSupportFolderOptions);
+        }
+
+        // Load the filtered solution to get the parent solution path and existing projects
+        SolutionModel filteredSolution = SlnFileFactory.CreateFromFilteredSolutionFile(_solutionFileFullPath);
+        string parentSolutionPath = filteredSolution.Description!; // The parent solution path is stored in Description
+
+        // Load the parent solution to validate projects exist in it
+        SolutionModel parentSolution = SlnFileFactory.CreateFromFileOrDirectory(parentSolutionPath);
+
+        // Get existing projects in the filter (already normalized to OS separator by CreateFromFilteredSolutionFile)
+        var existingProjects = filteredSolution.SolutionProjects.Select(p => p.FilePath).ToHashSet();
+
+        // Get solution-relative paths for new projects
+        var newProjects = ValidateAndGetNewProjects(projectPaths, parentSolution, parentSolutionPath, existingProjects);
+
+        // Add new projects to the existing list and save
+        var allProjects = existingProjects.Concat(newProjects).OrderBy(p => p);
+        SlnfFileHelper.SaveSolutionFilter(_solutionFileFullPath, parentSolutionPath, allProjects);
+    }
+
+    private List<string> ValidateAndGetNewProjects(
+        IEnumerable<string> projectPaths,
+        SolutionModel parentSolution,
+        string parentSolutionPath,
+        HashSet<string> existingProjects)
+    {
+        var newProjects = new List<string>();
+        string parentSolutionDirectory = Path.GetDirectoryName(parentSolutionPath) ?? string.Empty;
+
+        foreach (var projectPath in projectPaths)
+        {
+            string parentSolutionRelativePath = Path.GetRelativePath(parentSolutionDirectory, projectPath);
+
+            // Normalize to OS separator for consistent comparison
+            parentSolutionRelativePath = SlnfFileHelper.NormalizePathSeparatorsToOS(parentSolutionRelativePath);
+
+            // Check if project exists in parent solution
+            var projectInParent = parentSolution.FindProject(parentSolutionRelativePath);
+            if (projectInParent is null)
+            {
+                Reporter.Error.WriteLine(CliStrings.ProjectNotFoundInTheSolution, parentSolutionRelativePath, parentSolutionPath);
+                continue;
+            }
+
+            // Check if project is already in the filter
+            if (existingProjects.Contains(parentSolutionRelativePath))
+            {
+                Reporter.Output.WriteLine(CliStrings.SolutionAlreadyContainsProject, _solutionFileFullPath, parentSolutionRelativePath);
+                continue;
+            }
+
+            newProjects.Add(parentSolutionRelativePath);
+            Reporter.Output.WriteLine(CliStrings.ProjectAddedToTheSolution, parentSolutionRelativePath);
+        }
+
+        return newProjects;
+    }
 }

src/Cli/dotnet/Commands/Solution/Migrate/SolutionMigrateCommand.cs

@@ -29,7 +29,9 @@ public override int Execute()
         {
             ConvertToSlnxAsync(slnFileFullPath, slnxFileFullPath, CancellationToken.None).Wait();
             return 0;
-        } catch (Exception ex) {
+        }
+        catch (Exception ex)
+        {
             throw new GracefulException(ex.Message, ex);
         }
     }

src/Cli/dotnet/Commands/Solution/Remove/SolutionRemoveCommand.cs

@@ -27,7 +27,7 @@ public SolutionRemoveCommand(ParseResult parseResult) : base(parseResult)
 
     public override int Execute()
     {
-        string solutionFileFullPath = SlnFileFactory.GetSolutionFileFullPath(_fileOrDirectory);
+        string solutionFileFullPath = SlnFileFactory.GetSolutionFileFullPath(_fileOrDirectory, includeSolutionFilterFiles: true);
         if (_projects.Count == 0)
         {
             throw new GracefulException(CliStrings.SpecifyAtLeastOneProjectToRemove);
@@ -43,7 +43,15 @@ public override int Execute()
                         ? MsbuildProject.GetProjectFileFromDirectory(p)
                         : p));
 
-            RemoveProjectsAsync(solutionFileFullPath, relativeProjectPaths, CancellationToken.None).GetAwaiter().GetResult();
+            // Check if we're working with a solution filter file
+            if (solutionFileFullPath.HasExtension(SlnfFileHelper.SlnfExtension))
+            {
+                RemoveProjectsFromSolutionFilter(solutionFileFullPath, relativeProjectPaths);
+            }
+            else
+            {
+                RemoveProjectsAsync(solutionFileFullPath, relativeProjectPaths, CancellationToken.None).GetAwaiter().GetResult();
+            }
             return 0;
         }
         catch (Exception ex) when (ex is not GracefulException)
@@ -124,10 +132,41 @@ private static async Task RemoveProjectsAsync(string solutionFileFullPath, IEnum
             {
                 solution.RemoveFolder(folder);
                 // After removal, adjust index and continue to avoid skipping folders after removal
-                i--; 
+                i--;
             }
         }
 
         await serializer.SaveAsync(solutionFileFullPath, solution, cancellationToken);
     }
+
+    private static void RemoveProjectsFromSolutionFilter(string slnfFileFullPath, IEnumerable<string> projectPaths)
+    {
+        // Load the filtered solution to get the parent solution path and existing projects
+        SolutionModel filteredSolution = SlnFileFactory.CreateFromFilteredSolutionFile(slnfFileFullPath);
+        string parentSolutionPath = filteredSolution.Description!; // The parent solution path is stored in Description
+
+        // Get existing projects in the filter
+        // Use case-insensitive comparer on Windows for file path comparison
+        var existingProjects = filteredSolution.SolutionProjects.Select(p => p.FilePath).ToHashSet();
+
+        // Remove specified projects
+        foreach (var projectPath in projectPaths)
+        {
+            // Normalize the path to be relative to parent solution
+            string normalizedPath = projectPath;
+
+            // Try to find and remove the project
+            if (existingProjects.Remove(normalizedPath))
+            {
+                Reporter.Output.WriteLine(CliStrings.ProjectRemovedFromTheSolution, normalizedPath);
+            }
+            else
+            {
+                Reporter.Output.WriteLine(CliStrings.ProjectNotFoundInTheSolution, normalizedPath);
+            }
+        }
+
+        // Save updated filter
+        SlnfFileHelper.SaveSolutionFilter(slnfFileFullPath, parentSolutionPath, existingProjects.OrderBy(p => p));
+    }
 }

src/Cli/dotnet/Commands/Store/StoreCommand.cs

@@ -20,7 +20,7 @@ private StoreCommand(IEnumerable<string> msbuildArgs, string msbuildPath = null)
 
     public static StoreCommand FromArgs(string[] args, string msbuildPath = null)
     {
-        var result = Parser.Parse(["dotnet", "store", ..args]);
+        var result = Parser.Parse(["dotnet", "store", .. args]);
         return FromParseResult(result, msbuildPath);
     }
 

src/Cli/dotnet/Commands/Test/MTP/TestApplicationActionQueue.cs

@@ -78,7 +78,7 @@ private async Task Read(BuildOptions buildOptions, TestOptions testOptions, Term
                 {
                     result = ExitCode.GenericFailure;
                 }
-                
+
                 lock (_lock)
                 {
                     if (_aggregateExitCode is null)

src/Cli/dotnet/Commands/Test/VSTest/TestCommand.cs

@@ -175,7 +175,7 @@ private static int ForwardToVSTestConsole(ParseResult parseResult, string[] args
 
     public static TestCommand FromArgs(string[] args, string? testSessionCorrelationId = null, string? msbuildPath = null)
     {
-        var parseResult = Parser.Parse(["dotnet", "test", ..args]);
+        var parseResult = Parser.Parse(["dotnet", "test", .. args]);
 
         // settings parameters are after -- (including --), these should not be considered by the parser
         string[] settings = [.. args.SkipWhile(a => a != "--")];
@@ -260,7 +260,8 @@ private static TestCommand FromParseResult(ParseResult result, string[] settings
 
 
         Dictionary<string, string> variables = VSTestForwardingApp.GetVSTestRootVariables();
-        foreach (var (rootVariableName, rootValue) in variables) {
+        foreach (var (rootVariableName, rootValue) in variables)
+        {
             testCommand.EnvironmentVariable(rootVariableName, rootValue);
             VSTestTrace.SafeWriteTrace(() => $"Root variable set {rootVariableName}:{rootValue}");
         }