Scan Indirect Project Dependencies Recursively

scanindirectdependencies.target

<?xml version="1.0" encoding="utf-8"?>
<Project ToolsVersion="12.0" DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
  <!-- All the stuff normally found in the project, then in the AfterBuild event... -->
  <Target Name="AfterBuild">
    <!-- Here's the call to the custom task to get the list of dependencies -->
    <ScanIndirectDependencies StartFolder="$(MSBuildProjectDirectory)"
                              StartProjectReferences="@(ProjectReference)"
                              Configuration="$(Configuration)">
      <Output TaskParameter="IndirectDependencies" ItemName="IndirectDependenciesToCopy" />
    </ScanIndirectDependencies>

    <!-- Only copy the file in if we won't stomp something already there -->
    <Copy SourceFiles="%(IndirectDependenciesToCopy.FullPath)"
          DestinationFolder="$(OutputPath)"
          Condition="!Exists('$(OutputPath)\%(IndirectDependenciesToCopy.Filename)%(IndirectDependenciesToCopy.Extension)')" />
  </Target>


  <!-- THE CUSTOM TASK! -->
  <UsingTask TaskName="ScanIndirectDependencies" TaskFactory="CodeTaskFactory" AssemblyFile="$(MSBuildToolsPath)\Microsoft.Build.Tasks.v12.0.dll">
    <ParameterGroup>
      <StartFolder Required="true" />
      <StartProjectReferences ParameterType="Microsoft.Build.Framework.ITaskItem[]" Required="true" />
      <Configuration Required="true" />
      <IndirectDependencies ParameterType="Microsoft.Build.Framework.ITaskItem[]" Output="true" />
    </ParameterGroup>
    <Task>
      <Reference Include="System.Xml"/>
      <Using Namespace="Microsoft.Build.Framework" />
      <Using Namespace="Microsoft.Build.Utilities" />
      <Using Namespace="System" />
      <Using Namespace="System.Collections.Generic" />
      <Using Namespace="System.IO" />
      <Using Namespace="System.Linq" />
      <Using Namespace="System.Xml" />
      <Code Type="Fragment" Language="cs">
      <![CDATA[
var projectReferences = new List<string>();
var toScan = new List<string>(StartProjectReferences.Select(p => Path.GetFullPath(Path.Combine(StartFolder, p.ItemSpec))));
var indirectDependencies = new List<string>();

bool rescan;
do{
  rescan = false;
  foreach(var projectReference in toScan.ToArray())
  {
    if(projectReferences.Contains(projectReference))
    {
      toScan.Remove(projectReference);
      continue;
    }

    Log.LogMessage(MessageImportance.Low, "Scanning project reference for other project references: {0}", projectReference);

    var doc = new XmlDocument();
    doc.Load(projectReference);
    var nsmgr = new XmlNamespaceManager(doc.NameTable);
    nsmgr.AddNamespace("msb", "http://schemas.microsoft.com/developer/msbuild/2003");
    var projectDirectory = Path.GetDirectoryName(projectReference);

    // Find all project references we haven't already seen
    var newReferences = doc
          .SelectNodes("/msb:Project/msb:ItemGroup/msb:ProjectReference/@Include", nsmgr)
          .Cast<XmlAttribute>()
          .Select(a => Path.GetFullPath(Path.Combine(projectDirectory, a.Value)));

    if(newReferences.Count() > 0)
    {
      Log.LogMessage(MessageImportance.Low, "Found new referenced projects: {0}", String.Join(", ", newReferences));
    }

    toScan.Remove(projectReference);
    projectReferences.Add(projectReference);

    // Add any new references to the list to scan and mark the flag
    // so we run through the scanning loop again.
    toScan.AddRange(newReferences);
    rescan = true;

    // Include the assembly that the project reference generates.
    var outputLocation = Path.Combine(Path.Combine(projectDirectory, "bin"), Configuration);
    var localAsm = Path.GetFullPath(Path.Combine(outputLocation, doc.SelectSingleNode("/msb:Project/msb:PropertyGroup/msb:AssemblyName", nsmgr).InnerText + ".dll"));
    if(!indirectDependencies.Contains(localAsm) && File.Exists(localAsm))
    {
      Log.LogMessage(MessageImportance.Low, "Added project assembly: {0}", localAsm);
      indirectDependencies.Add(localAsm);
    }

    // Include third-party assemblies referenced by file location.
    var externalReferences = doc
          .SelectNodes("/msb:Project/msb:ItemGroup/msb:Reference/msb:HintPath", nsmgr)
          .Cast<XmlElement>()
          .Select(a => Path.GetFullPath(Path.Combine(projectDirectory, a.InnerText.Trim())))
          .Where(e => !indirectDependencies.Contains(e));

    Log.LogMessage(MessageImportance.Low, "Found new indirect references: {0}", String.Join(", ", externalReferences));
    indirectDependencies.AddRange(externalReferences);
  }
} while(rescan);

// Expand to include pdb and xml.
var xml = indirectDependencies.Select(f => Path.Combine(Path.GetDirectoryName(f), Path.GetFileNameWithoutExtension(f) + ".xml")).Where(f => File.Exists(f)).ToArray();
var pdb = indirectDependencies.Select(f => Path.Combine(Path.GetDirectoryName(f), Path.GetFileNameWithoutExtension(f) + ".pdb")).Where(f => File.Exists(f)).ToArray();
indirectDependencies.AddRange(xml);
indirectDependencies.AddRange(pdb);
Log.LogMessage("Located indirect references:\n{0}", String.Join(Environment.NewLine, indirectDependencies));

// Finally, assign the output parameter.
IndirectDependencies = indirectDependencies.Select(i => new TaskItem(i)).ToArray();
      ]]>
      </Code>
    </Task>
  </UsingTask>
</Project>