fixes for VsoAgent so that we can build on azure pipelines

Author: arturcic

src/GitVersionCore.Tests/ExecuteCoreTests.cs

@@ -1,4 +1,4 @@
-using GitTools.Testing;
+using GitTools.Testing;
 using GitVersion;
 using GitVersion.Helpers;
 using GitVersionCore.Tests;
@@ -270,6 +270,7 @@ LogMessages RepositoryScope(ExecuteCore executeCore = null, Action<EmptyReposito
         // Make sure GitVersion doesn't trigger build server mode when we are running the tests
         Environment.SetEnvironmentVariable(AppVeyor.EnvironmentVariableName, null);
         Environment.SetEnvironmentVariable(TravisCI.EnvironmentVariableName, null);
+        Environment.SetEnvironmentVariable(VsoAgent.EnvironmentVariableName, null);
         var debugBuilder = new StringBuilder();
         Action<string> debugLogger = s =>
         {
@@ -315,4 +316,4 @@ LogMessages RepositoryScope(ExecuteCore executeCore = null, Action<EmptyReposito
             Error = errorBuilder.ToString()
         };
     }
-}
+}

src/GitVersionCore/BuildServers/VsoAgent.cs

@@ -1,14 +1,16 @@
-namespace GitVersion
+namespace GitVersion
 {
     using System;
     using System.Linq;
     using System.Text.RegularExpressions;
 
     public class VsoAgent : BuildServerBase
     {
+        public const string EnvironmentVariableName = "TF_BUILD";
+
         public override bool CanApplyToCurrentContext()
         {
-            return !string.IsNullOrEmpty(Environment.GetEnvironmentVariable("TF_BUILD"));
+            return !string.IsNullOrEmpty(Environment.GetEnvironmentVariable(EnvironmentVariableName));
         }
 
         public override string[] GenerateSetParameterMessage(string name, string value)

src/GitVersionExe.Tests/GitVersionHelper.cs

@@ -1,4 +1,4 @@
-using System;
+using System;
 using System.Collections.Generic;
 using System.IO;
 using System.Text;
@@ -40,6 +40,7 @@ static ExecutionResults ExecuteIn(ArgumentBuilder arguments)
                 new KeyValuePair<string, string>(TeamCity.EnvironmentVariableName, arguments.IsTeamCity ? "8.0.0" : null),
                 new KeyValuePair<string, string>(AppVeyor.EnvironmentVariableName, null),
                 new KeyValuePair<string, string>(TravisCI.EnvironmentVariableName, null),
+                new KeyValuePair<string, string>(VsoAgent.EnvironmentVariableName, null),
             };
 
         var exitCode = -1;
@@ -82,4 +83,4 @@ static ExecutionResults ExecuteIn(ArgumentBuilder arguments)
 
         return new ExecutionResults(exitCode, output.ToString(), logContents);
     }
-}
+}

src/GitVersionTask.Tests/GitVersionTask.Tests.csproj

@@ -46,7 +46,7 @@
     <PackageReference Include="Microsoft.CodeAnalysis.Common" Version="1.3.2"></PackageReference>
     <PackageReference Include="Microsoft.CodeAnalysis.CSharp" Version="1.3.2"></PackageReference>
     <PackageReference Include="Microsoft.CodeAnalysis.VisualBasic" Version="1.3.2"></PackageReference>
-    <PackageReference Include="Newtonsoft.Json" Version="8.0.3"></PackageReference>
+    <PackageReference Include="Newtonsoft.Json" Version="10.0.3"></PackageReference>
     <PackageReference Include="NSubstitute" Version="1.10.0"></PackageReference>
     <PackageReference Include="NUnit" Version="3.9.0"></PackageReference>
     <packagereference Include="NUnit3TestAdapter" Version="3.9.0"></packagereference>