Cleaner stacktraces.

Here's a typical stack-trace:

System.NullReferenceException: Object reference not set to an instance of an object.
   at Contoso.Calculator.Host.Configuration.ReadConfiguration() in  C:\Users\bob\repos\Contoso\Calculator\Host\Configuration.cs:line 14
   at Contoso.Calculator.Host.Program.Initialise() in C:\Users\bob\repos\Contoso\Calculator\Host\Program.cs:line 23
   at Contoso.Calculator.Host.Program.Main() in C:\Users\bob\repos\Contoso\Calculator\Host\Program.cs:line 5

I don't know about you, but I'm not a huge fan of leaking the build path of my software - it's verbose, and, if you build all your software in C:\Temp\Garbage like a former colleague did, unprofessional looking.

The good thing is, this is easily fixed using the PathMap property. Simply add the following to your Directory.Build.props file

<PropertyGroup Label="Normalise stack trace file locations">
  <PathMap>$([System.IO.Path]::GetFullPath('$(MSBuildThisFileDirectory)'))=X:\</PathMap>
</PropertyGroup>

Your stack trace will now look much neater

System.NullReferenceException: Object reference not set to an instance of an object.
   at Contoso.Calculator.Host.Configuration.ReadConfiguration() in X:\Calculator\Host\Configuration.cs:line 14
   at Contoso.Calculator.Host.Program.Initialise() in X:\Calculator\Host\Program.cs:line 23
   at Contoso.Calculator.Host.Program.Main() in X:\Host\Program.cs:line 5

Note that you might want to hide the full path when building on a build-server, but show it when building on your local machine. This is easily achieved by adding a condition to the PropertyGroup:

<PropertyGroup 
    Label="Normalise stack trace file locations" 
    Condition="$(BuildingInsideVisualStudio) != 'true'">