Replacing DeepClone with a call that creates a copy of the project using the template csproj under a new ProjectCollection everytime.

src/Microsoft.DotNet.ProjectJsonMigration/MigrationSettings.cs

@@ -2,11 +2,14 @@
 // Licensed under the MIT license. See LICENSE file in the project root for full license information.
 
 using Microsoft.Build.Construction;
+using Microsoft.Build.Evaluation;
 
 namespace Microsoft.DotNet.ProjectJsonMigration
 {
     internal class MigrationSettings
     {
+        private string _msBuildProjectTemplatePath;
+
         public string ProjectXProjFilePath { get; }
         public string ProjectDirectory { get; }
         public string OutputDirectory { get; }
@@ -20,14 +23,58 @@ namespace Microsoft.DotNet.ProjectJsonMigration
             string sdkPackageVersion,
             ProjectRootElement msBuildProjectTemplate,
             string projectXprojFilePath=null,
+            string sdkDefaultsFilePath=null) : this(
+                projectDirectory, outputDirectory, sdkPackageVersion, projectXprojFilePath, sdkDefaultsFilePath)
+        {
+            MSBuildProjectTemplate = msBuildProjectTemplate != null ? msBuildProjectTemplate.DeepClone() : null;
+        }
+
+        public MigrationSettings(
+            string projectDirectory,
+            string outputDirectory,
+            string sdkPackageVersion,
+            string msBuildProjectTemplatePath,
+            string projectXprojFilePath=null,
+            string sdkDefaultsFilePath=null) : this(
+                projectDirectory, outputDirectory, sdkPackageVersion, projectXprojFilePath, sdkDefaultsFilePath)
+        {
+            _msBuildProjectTemplatePath = msBuildProjectTemplatePath;
+            MSBuildProjectTemplate = ProjectRootElement.Open(
+                _msBuildProjectTemplatePath,
+                new ProjectCollection(),
+                preserveFormatting: true);
+        }
+
+        private MigrationSettings(
+            string projectDirectory,
+            string outputDirectory,
+            string sdkPackageVersion,
+            string projectXprojFilePath=null,
             string sdkDefaultsFilePath=null)
         {
             ProjectDirectory = projectDirectory;
             OutputDirectory = outputDirectory;
             SdkPackageVersion = sdkPackageVersion;
-            MSBuildProjectTemplate = msBuildProjectTemplate != null ? msBuildProjectTemplate.DeepClone() : null;
             ProjectXProjFilePath = projectXprojFilePath;
             SdkDefaultsFilePath = sdkDefaultsFilePath;
         }
+
+        public ProjectRootElement CloneMSBuildProjectTemplate()
+        {
+            ProjectRootElement msBuildProjectTemplateClone = null;
+            if(!string.IsNullOrEmpty(_msBuildProjectTemplatePath))
+            {
+                msBuildProjectTemplateClone = ProjectRootElement.Open(
+                    _msBuildProjectTemplatePath,
+                    new ProjectCollection(),
+                    preserveFormatting: true);
+            }
+            else if(MSBuildProjectTemplate != null)
+            {
+                msBuildProjectTemplateClone = MSBuildProjectTemplate.DeepClone();
+            }
+
+            return msBuildProjectTemplateClone;
+        }
     }
 }

src/Microsoft.DotNet.ProjectJsonMigration/ProjectMigrator.cs

@@ -37,7 +37,7 @@ namespace Microsoft.DotNet.ProjectJsonMigration
             MigrationRuleInputs rootInputs = ComputeMigrationRuleInputs(rootSettings);
             IEnumerable<ProjectDependency> projectDependencies = null;
 
-            var tempMSBuildProjectTemplate = rootSettings.MSBuildProjectTemplate.DeepClone();
+            var tempMSBuildProjectTemplate = rootSettings.CloneMSBuildProjectTemplate();
 
             try
             {

src/dotnet/commands/dotnet-migrate/MigrateCommand.cs

@@ -24,8 +24,6 @@ namespace Microsoft.DotNet.Tools.Migrate
         private readonly string _reportFile;
         private readonly bool _reportFormatJson;
 
-        private readonly TemporaryDotnetNewTemplateProject _temporaryDotnetNewProject;
-
         public MigrateCommand(
             string templateFile, 
             string projectArg, 
@@ -40,21 +38,18 @@ namespace Microsoft.DotNet.Tools.Migrate
             _sdkVersion = sdkVersion;
             _xprojFilePath = xprojFilePath;
             _skipProjectReferences = skipProjectReferences;
-            _temporaryDotnetNewProject = new TemporaryDotnetNewTemplateProject();
             _reportFile = reportFile;
             _reportFormatJson = reportFormatJson;
         }
 
         public int Execute()
         {
+            var temporaryDotnetNewProject = new TemporaryDotnetNewTemplateProject();
             var projectsToMigrate = GetProjectsToMigrate(_projectArg);
 
-            var msBuildTemplate = _templateFile != null ?
+            var msBuildTemplatePath = _templateFile ?? temporaryDotnetNewProject.MSBuildProjectPath;
-                ProjectRootElement.Open(_templateFile,
-                    ProjectCollection.GlobalProjectCollection,
-                    preserveFormatting: true) : _temporaryDotnetNewProject.MSBuildProject;
             
-            var sdkVersion = _sdkVersion ?? _temporaryDotnetNewProject.MSBuildProject.GetSdkVersion();
+            var sdkVersion = _sdkVersion ?? temporaryDotnetNewProject.MSBuildProject.GetSdkVersion();
 
             EnsureNotNull(sdkVersion, "Null Sdk Version");
 
@@ -64,7 +59,12 @@ namespace Microsoft.DotNet.Tools.Migrate
             {
                 var projectDirectory = Path.GetDirectoryName(project);
                 var outputDirectory = projectDirectory;
-                var migrationSettings = new MigrationSettings(projectDirectory, outputDirectory, sdkVersion, msBuildTemplate, _xprojFilePath);
+                var migrationSettings = new MigrationSettings(
+                    projectDirectory,
+                    outputDirectory,
+                    sdkVersion,
+                    msBuildTemplatePath,
+                    _xprojFilePath);
                 var projectMigrationReport = new ProjectMigrator().Migrate(migrationSettings, _skipProjectReferences);
 
                 if (migrationReport == null)
@@ -79,6 +79,8 @@ namespace Microsoft.DotNet.Tools.Migrate
 
             WriteReport(migrationReport);
 
+            temporaryDotnetNewProject.Clean();
+
             return migrationReport.FailedProjectsCount;
         }
 

src/dotnet/commands/dotnet-migrate/TemporaryDotnetNewTemplateProject.cs

@@ -16,12 +16,18 @@ namespace Microsoft.DotNet.Tools.Migrate
 
         public ProjectRootElement MSBuildProject { get; }
 
+        public string MSBuildProjectPath
+        {
+            get
+            {
+                return Path.Combine(_projectDirectory, c_temporaryDotnetNewMSBuildProjectName + ".csproj");
+            }
+        }
+
         public TemporaryDotnetNewTemplateProject()
         {
             _projectDirectory = CreateDotnetNewMSBuild(c_temporaryDotnetNewMSBuildProjectName);
-            MSBuildProject = GetMSBuildProject(_projectDirectory);
+            MSBuildProject = GetMSBuildProject();
-
-            Clean();
         }
 
         public void Clean()
@@ -48,12 +54,10 @@ namespace Microsoft.DotNet.Tools.Migrate
             return tempDir;
         }
 
-        private ProjectRootElement GetMSBuildProject(string temporaryDotnetNewMSBuildDirectory)
+        private ProjectRootElement GetMSBuildProject()
         {
-            var templateProjPath = Path.Combine(temporaryDotnetNewMSBuildDirectory,
+            return ProjectRootElement.Open(
-                c_temporaryDotnetNewMSBuildProjectName + ".csproj");
+                MSBuildProjectPath,
-
-            return ProjectRootElement.Open(templateProjPath,
                 ProjectCollection.GlobalProjectCollection,
                 preserveFormatting: true);
         }