sln-add: --include-references when adding a project

src/Cli/dotnet/Commands/CliCommandStrings.resx

@@ -2483,4 +2483,7 @@ To display a value, specify the corresponding command-line option without provid
   <data name="ZeroTestsRan" xml:space="preserve">
     <value>Zero tests ran</value>
   </data>
-</root>
+  <data name="SolutionAddReferencedProjectsOptionDescription" xml:space="preserve">
+    <value>Recursively add projects' ReferencedProjects to solution</value>
+  </data>
+</root>

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

@@ -22,6 +22,7 @@ internal class SolutionAddCommand : CommandBase
     private readonly IReadOnlyCollection<string> _projects;
     private readonly string? _solutionFolderPath;
     private string _solutionFileFullPath = string.Empty;
+    private bool _includeReferences;
 
     private static string GetSolutionFolderPathWithForwardSlashes(string path)
     {
@@ -43,6 +44,7 @@ public SolutionAddCommand(ParseResult parseResult) : base(parseResult)
         _projects = (IReadOnlyCollection<string>)(parseResult.GetValue(SolutionAddCommandParser.ProjectPathArgument) ?? []);
         _inRoot = parseResult.GetValue(SolutionAddCommandParser.InRootOption);
         _solutionFolderPath = parseResult.GetValue(SolutionAddCommandParser.SolutionFolderOption);
+        _includeReferences = parseResult.GetValue(SolutionAddCommandParser.IncludeReferencesOption);
         SolutionArgumentValidator.ParseAndValidateArguments(_fileOrDirectory, _projects, SolutionArgumentValidator.CommandType.Add, _inRoot, _solutionFolderPath);
         _solutionFileFullPath = SlnFileFactory.GetSolutionFileFullPath(_fileOrDirectory);
     }
@@ -138,7 +140,7 @@ private async Task AddProjectsToSolutionAsync(IEnumerable<string> projectPaths,
         await serializer.SaveAsync(_solutionFileFullPath, solution, cancellationToken);
     }
 
-    private void AddProject(SolutionModel solution, string fullProjectPath, ISolutionSerializer serializer = null)
+    private void AddProject(SolutionModel solution, string fullProjectPath, ISolutionSerializer serializer = null, bool showMessageOnDuplicate = true)
     {
         string solutionRelativeProjectPath = Path.GetRelativePath(Path.GetDirectoryName(_solutionFileFullPath), fullProjectPath);
 
@@ -175,7 +177,10 @@ private void AddProject(SolutionModel solution, string fullProjectPath, ISolutio
         }
         catch (SolutionArgumentException ex) when (ex.Type == SolutionErrorType.DuplicateProjectName || solution.FindProject(solutionRelativeProjectPath) is not null)
         {
-            Reporter.Output.WriteLine(CliStrings.SolutionAlreadyContainsProject, _solutionFileFullPath, solutionRelativeProjectPath);
+            if (showMessageOnDuplicate)
+            {
+                Reporter.Output.WriteLine(CliStrings.SolutionAlreadyContainsProject, _solutionFileFullPath, solutionRelativeProjectPath);
+            }
             return;
         }
 
@@ -205,5 +210,17 @@ private void AddProject(SolutionModel solution, string fullProjectPath, ISolutio
         }
 
         Reporter.Output.WriteLine(CliStrings.ProjectAddedToTheSolution, solutionRelativeProjectPath);
+
+        // Get referencedprojects from the project instance
+        var referencedProjectsFullPaths = projectInstance.GetItems("ProjectReference")
+            .Select(item => Path.GetFullPath(item.EvaluatedInclude, Path.GetDirectoryName(fullProjectPath)));
+
+        if (_includeReferences)
+        {
+            foreach (var referencedProjectFullPath in referencedProjectsFullPaths)
+            {
+                AddProject(solution, referencedProjectFullPath, serializer, showMessageOnDuplicate: false);
+            }
+        }
     }
 }

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

@@ -4,6 +4,7 @@
 #nullable disable
 
 using System.CommandLine;
+using System.CommandLine.Parsing;
 
 namespace Microsoft.DotNet.Cli.Commands.Solution.Add;
 
@@ -26,6 +27,12 @@ public static class SolutionAddCommandParser
         Description = CliCommandStrings.AddProjectSolutionFolderArgumentDescription
     };
 
+    public static readonly Option<bool> IncludeReferencesOption = new("--include-references")
+    {
+        Description = CliCommandStrings.SolutionAddReferencedProjectsOptionDescription,
+        DefaultValueFactory = (_) => true,
+    };
+
     private static readonly Command Command = ConstructCommand();
 
     public static Command GetCommand()
@@ -40,6 +47,7 @@ private static Command ConstructCommand()
         command.Arguments.Add(ProjectPathArgument);
         command.Options.Add(InRootOption);
         command.Options.Add(SolutionFolderOption);
+        command.Options.Add(IncludeReferencesOption);
 
         command.SetAction((parseResult) => new SolutionAddCommand(parseResult).Execute());
 

test/TestAssets/TestProjects/SlnFileWithReferencedProjects/A/A.csproj

@@ -0,0 +1,12 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>net10.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+  </PropertyGroup>
+  <ItemGroup>
+    <ProjectReference Include="..\B\B.csproj" />
+  </ItemGroup>
+</Project>

test/TestAssets/TestProjects/SlnFileWithReferencedProjects/App.sln

@@ -0,0 +1,14 @@
+
+Microsoft Visual Studio Solution File, Format Version 12.00
+# Visual Studio Version 17
+VisualStudioVersion = 17.0.31903.59
+MinimumVisualStudioVersion = 10.0.40219.1
+Global
+	GlobalSection(SolutionConfigurationPlatforms) = preSolution
+		Debug|Any CPU = Debug|Any CPU
+		Release|Any CPU = Release|Any CPU
+	EndGlobalSection
+	GlobalSection(SolutionProperties) = preSolution
+		HideSolutionNode = FALSE
+	EndGlobalSection
+EndGlobal

test/TestAssets/TestProjects/SlnFileWithReferencedProjects/App.slnx

@@ -0,0 +1,2 @@
+<Solution>
+</Solution>

test/TestAssets/TestProjects/SlnFileWithReferencedProjects/B/B.csproj

@@ -0,0 +1,10 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>net10.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+  </PropertyGroup>
+
+</Project>

test/dotnet.Tests/CommandTests/Solution/Add/GivenDotnetSlnAdd.cs

@@ -8,6 +8,7 @@
 using Microsoft.VisualStudio.SolutionPersistence;
 using Microsoft.VisualStudio.SolutionPersistence.Model;
 using Microsoft.DotNet.Cli.Commands;
+using System.Threading.Tasks;
 
 namespace Microsoft.DotNet.Cli.Sln.Add.Tests
 {
@@ -36,6 +37,7 @@ dotnet solution <SLN_FILE> add [<PROJECT_PATH>...] [options]
 Options:
   --in-root                                  Place project in root of the solution, rather than creating a solution folder.
   -s, --solution-folder <solution-folder>    The destination solution folder path to add the projects to.
+  --include-references                       Recursively add projects' ReferencedProjects to solution [default: True]
   -?, -h, --help                             Show command line help";
 
         public GivenDotnetSlnAdd(ITestOutputHelper log) : base(log)
@@ -1154,6 +1156,40 @@ public async Task WhenAddingProjectOutsideDirectoryItShouldNotAddSolutionFolders
             solution.SolutionFolders.Count.Should().Be(0);
         }
 
+        [Theory]
+        [InlineData("sln", ".sln", "--include-references=true")]
+        [InlineData("solution", ".sln", "--include-references=true")]
+        [InlineData("sln", ".slnx", "--include-references=true")]
+        [InlineData("solution", ".slnx", "--include-references=true")]
+        [InlineData("sln", ".sln", "--include-references=false")]
+        [InlineData("solution", ".sln", "--include-references=false")]
+        [InlineData("sln", ".slnx", "--include-references=false")]
+        [InlineData("solution", ".slnx", "--include-references=false")]
+        public async Task WhenSolutionIsPassedAProjectWithReferenceItAddsOtherProjectUnlessSpecified(string solutionCommand, string solutionExtension, string option)
+        {
+            var projectDirectory = _testAssetsManager
+                .CopyTestAsset("SlnFileWithReferencedProjects", identifier: $"GivenDotnetSlnAdd-{solutionCommand}")
+                .WithSource()
+                .Path;
+            var projectToAdd = Path.Combine("A", "A.csproj");
+            var cmd = new DotnetCommand(Log)
+                .WithWorkingDirectory(Path.Join(projectDirectory))
+                .Execute(solutionCommand, $"App{solutionExtension}", "add", projectToAdd, option);
+            cmd.Should().Pass();
+            // Should have two projects
+            ISolutionSerializer serializer = SolutionSerializers.GetSerializerByMoniker(Path.Join(projectDirectory, $"App{solutionExtension}"));
+            SolutionModel solution = await serializer.OpenAsync(Path.Join(projectDirectory, $"App{solutionExtension}"), CancellationToken.None);
+
+            if (option.Equals("--include-references=false")) // Option is true by default
+            {
+                solution.SolutionProjects.Count.Should().Be(1);
+            }
+            else
+            {
+                solution.SolutionProjects.Count.Should().Be(2);
+            }
+        }
+
         private string GetExpectedSlnContents(
             string slnPath,
             string slnTemplateName,
@@ -1237,6 +1273,8 @@ public void WhenSolutionIsPassedAsProjectWithSolutionFolderItPrintsSuggestionAnd
         {
             VerifySuggestionAndUsage(solutionCommand, "--solution-folder", solutionExtension);
         }
+
+
         private void VerifySuggestionAndUsage(string solutionCommand, string arguments, string solutionExtension)
         {
             var projectDirectory = _testAssetsManager

test/dotnet.Tests/CompletionTests/snapshots/bash/DotnetCliSnapshotTests.VerifyCompletions.verified.sh

@@ -1421,7 +1421,7 @@ _testhost_solution_add() {
     prev="${COMP_WORDS[COMP_CWORD-1]}" 
     COMPREPLY=()
 
-    opts="--in-root --solution-folder --help" 
+    opts="--in-root --solution-folder --include-references --help" 
 
     if [[ $COMP_CWORD == "$1" ]]; then
         COMPREPLY=( $(compgen -W "$opts" -- "$cur") )
@@ -1433,6 +1433,10 @@ _testhost_solution_add() {
             COMPREPLY=( $(compgen -W "False True" -- "$cur") )
             return
         ;;
+        --include-references)
+            COMPREPLY=( $(compgen -W "False True" -- "$cur") )
+            return
+        ;;
     esac
 
     COMPREPLY=( $(compgen -W "$opts" -- "$cur") )

test/dotnet.Tests/CompletionTests/snapshots/pwsh/DotnetCliSnapshotTests.VerifyCompletions.verified.ps1

@@ -840,6 +840,7 @@ Register-ArgumentCompleter -Native -CommandName 'testhost' -ScriptBlock {
                 [CompletionResult]::new('--in-root', '--in-root', [CompletionResultType]::ParameterName, "Place project in root of the solution, rather than creating a solution folder.")
                 [CompletionResult]::new('--solution-folder', '--solution-folder', [CompletionResultType]::ParameterName, "The destination solution folder path to add the projects to.")
                 [CompletionResult]::new('--solution-folder', '-s', [CompletionResultType]::ParameterName, "The destination solution folder path to add the projects to.")
+                [CompletionResult]::new('--include-references', '--include-references', [CompletionResultType]::ParameterName, "Recursively add projects`' ReferencedProjects to solution")
                 [CompletionResult]::new('--help', '--help', [CompletionResultType]::ParameterName, "Show command line help.")
                 [CompletionResult]::new('--help', '-h', [CompletionResultType]::ParameterName, "Show command line help.")
             )