added test of Jenkins GetCurrentBranch method

Author: Behrhorst

src/GitVersionCore.Tests/BuildServers/EnvironmentVariableJenkinsTests.cs

@@ -7,6 +7,8 @@
 public class EnvironmentVariableJenkinsTests
 {
     string key = "JENKINS_URL";
+    string branch = "GIT_BRANCH";
+    string localBranch = "GIT_LOCAL_BRANCH";
 
     private void SetEnvironmentVariableForDetection()
     {
@@ -33,4 +35,24 @@ public void CanNotApplyCurrentContextWhenEnvironmentVariableIsNotSet()
         var j = new Jenkins();
         j.CanApplyToCurrentContext().ShouldBe(false);  
     }
+
+    [Test]
+    public void JenkinsTakesLocalBranchNameNotRemoteName()
+    {
+        // Save original values so they can be restored
+        string branchOrig = Environment.GetEnvironmentVariable(branch);
+        string localBranchOrig = Environment.GetEnvironmentVariable(localBranch);
+
+        // Set new Environment variables for testing
+        Environment.SetEnvironmentVariable(branch, "origin/master");
+        Environment.SetEnvironmentVariable(localBranch, "master");
+
+        // Test Jenkins GetCurrentBranch method
+        var j = new Jenkins();
+        j.GetCurrentBranch(true).ShouldBe("master");
+
+        // Restore environment variables
+        Environment.SetEnvironmentVariable(branch, branchOrig);
+        Environment.SetEnvironmentVariable(localBranch, localBranchOrig);
+    }
 }