Fixing on PR comments

src/dotnet/MsbuildProject.cs

@@ -1,6 +1,10 @@
 // Copyright (c) .NET Foundation and contributors. All rights reserved.
 // Licensed under the MIT license. See LICENSE file in the project root for full license information.
 
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
 using Microsoft.Build.Construction;
 using Microsoft.Build.Evaluation;
 using Microsoft.Build.Exceptions;
@@ -8,10 +12,6 @@ using Microsoft.DotNet.Cli.Utils;
 using Microsoft.DotNet.Tools.Common;
 using Microsoft.DotNet.Tools.ProjectExtensions;
 using NuGet.Frameworks;
-using System;
-using System.Collections.Generic;
-using System.IO;
-using System.Linq;
 
 namespace Microsoft.DotNet.Tools
 {
@@ -61,6 +61,19 @@ namespace Microsoft.DotNet.Tools
         }
 
         public static MsbuildProject FromDirectory(ProjectCollection projects, string projectDirectory)
+        {
+            FileInfo projectFile = GetProjectFileFromDirectory(projectDirectory);
+
+            var project = TryOpenProject(projects, projectFile.FullName);
+            if (project == null)
+            {
+                throw new GracefulException(CommonLocalizableStrings.FoundInvalidProject, projectFile.FullName);
+            }
+
+            return new MsbuildProject(projects, project);
+        }
+
+        public static FileInfo GetProjectFileFromDirectory(string projectDirectory)
         {
             DirectoryInfo dir;
             try
@@ -90,22 +103,7 @@ namespace Microsoft.DotNet.Tools
                 throw new GracefulException(CommonLocalizableStrings.MoreThanOneProjectInDirectory, projectDirectory);
             }
 
-            FileInfo projectFile = files.First();
+            return files.First();
-
-            if (!projectFile.Exists)
-            {
-                throw new GracefulException(
-                    CommonLocalizableStrings.CouldNotFindAnyProjectInDirectory,
-                    projectDirectory);
-            }
-
-            var project = TryOpenProject(projects, projectFile.FullName);
-            if (project == null)
-            {
-                throw new GracefulException(CommonLocalizableStrings.FoundInvalidProject, projectFile.FullName);
-            }
-
-            return new MsbuildProject(projects, project);
         }
 
         public int AddProjectToProjectReferences(string framework, IEnumerable<string> refs)
@@ -120,7 +118,7 @@ namespace Microsoft.DotNet.Tools
                 if (ProjectRootElement.HasExistingItemWithCondition(framework, @ref))
                 {
                     Reporter.Output.WriteLine(string.Format(
-                        CommonLocalizableStrings.ProjectAlreadyHasAreference, 
+                        CommonLocalizableStrings.ProjectAlreadyHasAreference,
                         @ref));
                     continue;
                 }
@@ -270,4 +268,4 @@ namespace Microsoft.DotNet.Tools
             }
         }
     }
-}
+}

src/dotnet/commands/dotnet-add/dotnet-add-package/LocalizableStrings.cs

@@ -11,6 +11,8 @@ namespace Microsoft.DotNet.Tools.Add.PackageReference
 
         public const string AppHelpText = "Package references to add";
 
+        public const string SpecifyExactlyOnePackageReference = "Please specify one package reference to add.";
+
         public const string CmdFrameworkDescription = "Add reference only when targetting a specific framework";
 
         public const string CmdNoRestoreDescription = "Add reference without performing restore preview and compatibility check.";
@@ -30,6 +32,5 @@ namespace Microsoft.DotNet.Tools.Add.PackageReference
         public const string CmdSource = "SOURCE";
 
         public const string CmdPackageDirectory = "PACKAGE_DIRECTORY";
-
     }
 }

src/dotnet/commands/dotnet-add/dotnet-add-package/Program.cs

@@ -28,7 +28,7 @@ namespace Microsoft.DotNet.Tools.Add.PackageReference
 
         public static DotNetSubCommandBase Create()
         {
-            var command = new AddPackageReferenceCommand()
+            var command = new AddPackageReferenceCommand
             {
                 Name = "package",
                 FullName = LocalizableStrings.AppFullName,
@@ -69,29 +69,38 @@ namespace Microsoft.DotNet.Tools.Add.PackageReference
 
         public override int Run(string fileOrDirectory)
         {
-            var projects = new ProjectCollection();
+            if (RemainingArguments.Count != 1)
-            var msbuildProj = MsbuildProject.FromFileOrDirectory(projects, fileOrDirectory);
-
-            if (RemainingArguments.Count == 0)
             {
-                throw new GracefulException(CommonLocalizableStrings.SpecifyAtLeastOneReferenceToAdd);
+                throw new GracefulException(LocalizableStrings.SpecifyExactlyOnePackageReference);
+            }
+
+            var projectFilePath = string.Empty;
+
+            if (!File.Exists(fileOrDirectory))
+            {
+                projectFilePath = MsbuildProject.GetProjectFileFromDirectory(fileOrDirectory).FullName;
+            }
+            else
+            {
+                projectFilePath = fileOrDirectory;
             }
 
             var tempDgFilePath = string.Empty;
-            if(!_noRestoreOption.HasValue())
+
+            if (!_noRestoreOption.HasValue())
             {
                 // Create a Dependency Graph file for the project
-                tempDgFilePath = CreateTemporaryFile(".dg");
+                tempDgFilePath = Path.GetTempFileName();
-                GetProjectDependencyGraph(msbuildProj.ProjectRootElement.FullPath, tempDgFilePath);
+                GetProjectDependencyGraph(projectFilePath, tempDgFilePath);
             }
 
-            var result = NuGetCommand.Run(TransformArgs(tempDgFilePath, msbuildProj.ProjectRootElement.FullPath));
+            var result = NuGetCommand.Run(TransformArgs(RemainingArguments.First(), tempDgFilePath, projectFilePath));
             DisposeTemporaryFile(tempDgFilePath);
+
             return result;
         }
 
-        private void GetProjectDependencyGraph(string projectFilePath,
+        private void GetProjectDependencyGraph(string projectFilePath, string dgFilePath)
-            string dgFilePath)
         {
             var args = new List<string>();
 
@@ -102,7 +111,7 @@ namespace Microsoft.DotNet.Tools.Add.PackageReference
             args.Add("/t:GenerateRestoreGraphFile");
 
             // Pass Dependency Graph file output path
-            args.Add(string.Format("/p:RestoreGraphOutputPath={0}{1}{2}", '"', dgFilePath, '"'));
+            args.Add($"/p:RestoreGraphOutputPath=\"{dgFilePath}\"");
 
             var result = new MSBuildForwardingApp(args).Execute();
 
@@ -112,14 +121,6 @@ namespace Microsoft.DotNet.Tools.Add.PackageReference
             }
         }
 
-        private string CreateTemporaryFile(string extension)
-        {
-            var tempDirectory = Path.GetTempPath();
-            var tempFile = Path.Combine(tempDirectory, Guid.NewGuid().ToString() + extension);
-            File.Create(tempFile).Dispose();
-            return tempFile;
-        }
-
         private void DisposeTemporaryFile(string filePath)
         {
             if (File.Exists(filePath))
@@ -128,37 +129,38 @@ namespace Microsoft.DotNet.Tools.Add.PackageReference
             }
         }
 
-        private string[] TransformArgs(string tempDgFilePath, string projectFilePath)
+        private string[] TransformArgs(string packageId, string tempDgFilePath, string projectFilePath)
         {
             var args = new List<string>(){
                 "package",
                 "add",
                 "--package",
-                "Newtonsoft.Json",
+                packageId,
                 "--project",
                 projectFilePath
             };
-            if(_versionOption.HasValue())
+
+            if (_versionOption.HasValue())
             {
                 args.Add("--version");
                 args.Add(_versionOption.Value());
             }
-            if(_sourceOption.HasValue())
+            if (_sourceOption.HasValue())
             {
                 args.Add("--source");
                 args.Add(_sourceOption.Value());
             }
-            if(_frameworkOption.HasValue())
+            if (_frameworkOption.HasValue())
             {
                 args.Add("--framework");
                 args.Add(_frameworkOption.Value());
             }
-            if(_packageDirectoryOption.HasValue())
+            if (_packageDirectoryOption.HasValue())
             {
                 args.Add("--package-directory");
                 args.Add(_packageDirectoryOption.Value());
             }
-            if(_noRestoreOption.HasValue())
+            if (_noRestoreOption.HasValue())
             {
                 args.Add("--no-restore");
             }