Add environment detection, for #313

Author: serra

src/GitVersionCore.Tests/BuildServers/EnvironmentVariableJenkinsTests.cs

@@ -0,0 +1,36 @@
+using System;
+using GitVersion;
+using NUnit.Framework;
+
+[TestFixture]
+public class EnvironmentVariableJenkinsTests
+{
+    string key = "JENKINS_URL";
+
+    private void SetEnvironmentVariableForDetection()
+    {
+        Environment.SetEnvironmentVariable(key, "a value", EnvironmentVariableTarget.Process);
+    }
+
+    private void ClearEnvironmentVariableForDetection()
+    {
+        Environment.SetEnvironmentVariable(key, null, EnvironmentVariableTarget.Process);
+    }
+
+    [Test, Explicit]
+    public void CanApplyCurrentContextWhenEnvironmentVariableIsSet()
+    {
+        SetEnvironmentVariableForDetection();
+        var j = new Jenkins();
+        Assert.True(j.CanApplyToCurrentContext());   
+    }
+    
+    [Test, Explicit]
+    public void CanNotApplyCurrentContextWhenEnvironmentVariableIsNotSet()
+    {
+        ClearEnvironmentVariableForDetection();
+        var j = new Jenkins();
+        Assert.False(j.CanApplyToCurrentContext());  
+    }
+
+}

src/GitVersionCore.Tests/GitVersionCore.Tests.csproj

@@ -97,6 +97,7 @@
   <ItemGroup>
     <Compile Include="BuildServers\BuildServerBaseTests.cs" />
     <Compile Include="BuildServers\ContinuaCiTests.cs" />
+    <Compile Include="BuildServers\EnvironmentVariableJenkinsTests.cs" />
     <Compile Include="BuildServers\MyGetTests.cs" />
     <Compile Include="BuildServers\TeamCityTests.cs" />
     <Compile Include="Fixtures\CommitCountingRepoFixture.cs" />

src/GitVersionCore/BuildServers/BuildServerList.cs

@@ -10,7 +10,8 @@ public static class BuildServerList
             new ContinuaCi(),
             new TeamCity(),
             new AppVeyor(),
-            new MyGet()
+            new MyGet(),
+            new Jenkins()
         };
 
         public static IEnumerable<IBuildServer> GetApplicableBuildServers()

src/GitVersionCore/BuildServers/Jenkins.cs

@@ -0,0 +1,32 @@
+namespace GitVersion
+{
+    using System;
+
+    public class Jenkins : BuildServerBase
+    {
+        // string _file = "gitversion.properties"
+
+        public override bool CanApplyToCurrentContext()
+        {
+            return !string.IsNullOrEmpty(Environment.GetEnvironmentVariable("JENKINS_URL__"));
+        }
+
+        public override string GenerateSetVersionMessage(string versionToUseForBuildNumber)
+        {
+            throw new NotImplementedException();
+            // tbd
+        }
+
+        public override string[] GenerateSetParameterMessage(string name, string value)
+        {
+            throw new NotImplementedException();
+            // this returns an array of property lines
+        }
+
+        public override void WriteIntegration(Action<string> writer, VersionVariables variables)
+        {
+            // log message that we're running on jenkins and writing a properties file
+            // foreach in GenerateSetParameterMessage write line to file
+        }
+    }
+}

src/GitVersionCore/GitVersionCore.csproj

@@ -71,6 +71,7 @@
     <Compile Include="BuildServers\ContinuaCi.cs" />
     <Compile Include="BuildServers\GitHelper.cs" />
     <Compile Include="BuildServers\IBuildServer.cs" />
+    <Compile Include="BuildServers\Jenkins.cs" />
     <Compile Include="BuildServers\MyGet.cs" />
     <Compile Include="BuildServers\TeamCity.cs" />
     <Compile Include="Configuration\BranchConfig.cs" />