Fixes to nuget install/uninstall script to use msbuild OM

src/Tools/Nuget/Core.nuspec

@@ -26,7 +26,7 @@
     <file src="..\..\..\bin\Release\ssc.exe" target="tools" />
     <file src="Core\Install.ps1" target="tools" />
     <file src="Core\Uninstall.ps1" target="tools" />
-    <file src="Core\Cleanup.psm1" target="tools" />
+    <file src="Core\Reset.psm1" target="tools" />
     <file src="Core\ScriptSharp.PlaceHolder.txt" target="content" />
   </files>
 </package>

src/Tools/Nuget/Core/Install.ps1

@@ -1,6 +1,6 @@
 param($installPath, $toolsPath, $package, $project)
 
-Import-Module (Join-Path $toolsPath "Cleanup.psm1")
+Import-Module (Join-Path $toolsPath "Reset.psm1")
 
 function Compute-RelativePath ($basePath, $referencePath) {
   $baseUri = New-Object -typename System.Uri -argumentlist $basePath
@@ -16,23 +16,18 @@ $placeholder = "ScriptSharp.PlaceHolder.txt"
 $project.ProjectItems.Item($placeholder).Remove()
 Split-Path $project.FullName -parent | Join-Path -ChildPath $placeholder | Remove-Item
 
-# save any out-standing changes to the project first before modifying the project file
-$project.Save()
-
-# load project file as xml document
-$doc = New-Object System.Xml.XmlDocument
-$doc.Load($project.FullName)
-$namespace = "http://schemas.microsoft.com/developer/msbuild/2003"
+# Get the msbuild object associated with the project
+Add-Type -AssemblyName "Microsoft.Build, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a"
+$msbuild = [Microsoft.Build.Evaluation.ProjectCollection]::GlobalProjectCollection.GetLoadedProjects($project.FullName)[0]
 
-# remove any old import reference in case one exists
-Cleanup-Project $doc $namespace
+# first remove any existing import reference
+Reset-Project $msbuild
 
-# add targets import by building a relative reference to targets file in package tools directory
+# get a relative reference to the targets file in the package's tools directory
+# and add it to the project
 $targetsAbsolutePath = Join-Path $toolsPath "ScriptSharp.targets"
 $targetsRelativePath = Compute-RelativePath $project.FullName $targetsAbsolutePath
-$importNode = $doc.CreateElement('Import', $namespace)
-$importNode.SetAttribute('Project', $targetsRelativePath)
-$doc.Project.AppendChild($importNode)
+$msbuild.Xml.AddImport($targetsRelativePath)
 
 # finally save the project
-$doc.Save($project.FullName)
+$project.Save()

src/Tools/Nuget/Core/Reset.psm1

@@ -0,0 +1,11 @@
+function Reset-Project($msbuild) {
+  $imports = $msbuild.Xml.Imports
+
+  if ($imports.Count -gt 0) {
+    foreach ($import in $imports) {
+      if ($import.Project.IndexOf("ScriptSharp.targets") -gt 0) {
+        $msbuild.Xml.RemoveChild($import)
+      }
+    }
+  }
+}

src/Tools/Nuget/Core/Uninstall.ps1

@@ -1,20 +1,13 @@
 param($installPath, $toolsPath, $package, $project)
 
-Import-Module (Join-Path $toolsPath "Cleanup.psm1")
+Import-Module (Join-Path $toolsPath "Reset.psm1")
 
-# save any unsaved changes first
-$project.Save()
-
-# load project file as xml document
-$doc = New-Object System.Xml.XmlDocument
-$doc.Load($project.FullName)
-$namespace = "http://schemas.microsoft.com/developer/msbuild/2003"
+# Get the msbuild object associated with the project and add an import
+Add-Type -AssemblyName "Microsoft.Build, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a"
+$msbuild = [Microsoft.Build.Evaluation.ProjectCollection]::GlobalProjectCollection.GetLoadedProjects($project.FullName)[0]
 
 # remove import reference
-Cleanup-Project $doc $namespace
+Reset-Project $msbuild
 
-# save changes
-$doc.Save($project.FullName)
-
-# reload the project since we made changes to the csproj
-$project.DTE.ExecuteCommand("Project.ReloadProject")
+# and then save the project
+$project.Save()