Add Travis-CI.

source/Nuke.Core.Tests/BuildServerTest.cs

@@ -56,6 +56,14 @@ public void TestJenkins(PropertyInfo property)
             AssertProperty(Jenkins.Instance.NotNull(), property);
         }
 
+        [BuildServerTheory(typeof(Travis))]
+        [MemberData(nameof(Properties), typeof(Travis))]
+        public void TestTravis(PropertyInfo property)
+        {
+            AssertProperty(Travis.Instance.NotNull(), property);
+            Assert.True(Travis.Instance.Ci);
+            Assert.True(Travis.Instance.ContinousIntegration);
+
         [BuildServerTheory(typeof(GitLab))]
         [MemberData(nameof(Properties),typeof(Jenkins))]
         public void TestGitLab(PropertyInfo property)

source/Nuke.Core/BuildServers/Travis.cs

@@ -0,0 +1,160 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using static Nuke.Core.EnvironmentInfo;
+
+namespace Nuke.Core.BuildServers
+{
+    /// <summary>
+    ///     Interface according to the <a href="https://docs.travis-ci.com/user/environment-variables/">official website</a>.
+    /// </summary>
+    [BuildServer]
+    public class Travis
+    {
+        private static Lazy<Travis> s_instance = new Lazy<Travis>(() => new Travis());
+
+        public static Travis Instance => NukeBuild.Instance?.Host == HostType.Travis ? s_instance.Value : null;
+
+        internal static bool IsRunningTravis => Variable("TRAVIS") != null;
+
+        internal Travis()
+        {
+        }
+
+        public bool Ci => EnsureVariable<bool>("CI");
+        public bool ContinousIntegration => EnsureVariable<bool>("CONTINUOUS_INTEGRATION");
+
+        /// <summary>
+        /// Whether you have defined any encrypted variables, including variables defined in the Repository Settings.
+        /// </summary>
+        public bool SecureEnvVars => EnsureVariable<bool>("TRAVIS_SECURE_ENV_VARS");
+
+
+        /// <summary>
+        /// Set to <c>true</c> if the job is allowed to fail otherwhise <c>false</c>.
+        /// </summary>
+        public bool AllowFailure => EnsureVariable<bool>("TRAVIS_ALLOW_FAILURE");
+
+        /// <summary>
+        /// For push builds, or builds not triggered by a pull request, this is the name of the branch.
+        /// For builds triggered by a pull request this is the name of the branch targeted by the pull request.
+        /// For builds triggered by a tag, this is the same as the name of the tag (<c>TRAVIS_TAG</c>).
+        /// </summary>
+        public string Branch => EnsureVariable("TRAVIS_BRANCH");
+
+        /// <summary>
+        /// The absolute path to the directory where the repository being built has been copied on the worker.
+        /// </summary>
+        public string BuildDir => EnsureVariable("TRAVIS_BUILD_DIR");
+
+        /// <summary>
+        ///  The id of the current build that Travis CI uses internally.
+        /// </summary>
+        public string BuildId => EnsureVariable("TRAVIS_BUILD_ID");
+
+        /// <summary>
+        /// The number of the current build (for example, “4”).
+        /// </summary>
+        public int BuildNumber => EnsureVariable<int>("TRAVIS_BUILD_NUMBER");
+
+        /// <summary>
+        /// The commit that the current build is testing.
+        /// </summary>
+        public string Commit => EnsureVariable("TRAVIS_COMMIT");
+
+        /// <summary>
+        /// The commit subject and body, unwrapped.
+        /// </summary>
+        public string CommitMessage => EnsureVariable("TRAVIS_COMMIT_MESSAGE");
+
+        /// <summary>
+        /// The range of commits that were included in the push or pull request. (Note that this is empty for builds triggered by the initial commit of a new branch.)
+        /// </summary>
+        public string CommitRange => Variable("TRAVIS_COMMIT_RANGE");
+
+        /// <summary>
+        /// Indicates how the build was triggered. 
+        /// </summary>
+        public TravisEventType EventType => EnsureVariable<TravisEventType>("TRAVIS_EVENT_TYPE");
+
+        /// <summary>
+        /// The id of the current job that Travis CI uses internally.
+        /// </summary>
+        public string JobId => EnsureVariable("TRAVIS_JOB_ID");
+
+        /// <summary>
+        /// The number of the current job (for example, “4.1”).
+        /// </summary>
+        public string JobNumber => EnsureVariable("TRAVIS_JOB_NUMBER");
+
+        /// <summary>
+        /// On multi-OS builds, this value indicates the platform the job is running on. Values are <c>linux</c> and <c>osx</c> currently, to be extended in the future.
+        /// </summary>
+        public string OsName => Variable("TRAVIS_OS_NAME");
+
+
+        /// <summary>
+        /// <c>TRAVIS_PULL_REQUEST</c> is set to the pull request number if the current job is a pull request build, or <c>false</c> if it’s not.
+        /// </summary>
+        public string PullRequest => EnsureVariable("TRAVIS_PULL_REQUEST");
+
+        /// <summary>
+        /// If the current job is a pull request, the name of the branch from which the PR originated.
+        /// If the current job is a push build, this variable is empty(<c>""</c>).
+        /// </summary>
+        public string PullRequestBranch => EnsureVariable("TRAVIS_PULL_REQUEST_BRANCH");
+
+        /// <summary>
+        /// If the current job is a pull request, the commit SHA of the HEAD commit of the PR.
+        /// If the current job is a push build, this variable is empty(<c>""</c>).
+        /// </summary>
+        public string PullRequestSha => EnsureVariable("TRAVIS_PULL_REQUEST_SHA");
+
+        /// <summary>
+        /// If the current job is a pull request, the slug (in the form <c>owner_name/repo_name</c>) of the repository from which the PR originated.
+        /// If the current job is a push build, this variable is empty(<c>""</c>).
+        /// </summary>
+        public string PullRequestSlug => EnsureVariable("TRAVIS_PULL_REQUEST_SLUG");
+
+        /// <summary>
+        /// The slug (in form: <c>owner_name/repo_name</c>) of the repository currently being built.
+        /// </summary>
+        public string RepoSlug => EnsureVariable("TRAVIS_REPO_SLUG");
+
+        /// <summary>
+        /// <c>true</c> or <c>false</c> based on whether sudo is enabled.
+        /// </summary>
+        public string Sudo => EnsureVariable("TRAVIS_SUDO");
+
+        /// <summary>
+        /// Is set to <em>0</em> if the build is successful and <em>1</em> if the build is broken.
+        /// </summary>
+        public string TestResult => EnsureVariable("TRAVIS_TEST_RESULT");
+
+        /// <summary>
+        /// If the current build is for a git tag, this variable is set to the tag’s name.
+        /// </summary>
+        public string Tag => Variable("TRAVIS_TAG");
+
+        public string DartVersion => Variable("TRAVIS_DARTVersion");
+        public string GoVersion => Variable("TRAVIS_GOVersion");
+        public string HaxeVersion => Variable("TRAVIS_HAXEVersion");
+        public string JdkVersion => Variable("TRAVIS_JDKVersion");
+        public string JuliaVersion => Variable("TRAVIS_JULIAVersion");
+        public string NodeVersion => Variable("TRAVIS_NODEVersion");
+        public string OtpRelease => Variable("TRAVIS_OTP_RELEASE");
+        public string PerlVersion => Variable("TRAVIS_PERLVersion");
+        public string PhpVersion => Variable("TRAVIS_PHPVersion");
+        public string PythonVersion => Variable("TRAVIS_PYTHONVersion");
+        public string RVersion => Variable("TRAVIS_RVersion");
+        public string RubyVersion => Variable("TRAVIS_RUBYVersion");
+        public string RustVersion => Variable("TRAVIS_RUSTVersion");
+        public string ScalaVersion => Variable("TRAVIS_SCALAVersion");
+        public string XCodeSdk => Variable("TRAVIS_XCODE_SDK");
+        public string XCodeScheme => Variable("TRAVIS_XCODE_SCHEME");
+        public string XCodeProject => Variable("TRAVIS_XCODE_PROJECT");
+        public string XCodeWorkspace => Variable("TRAVIS_XCODE_WORKSPACE");
+    }
+}

source/Nuke.Core/BuildServers/TravisEventType.cs

@@ -0,0 +1,17 @@
+using System.Diagnostics.CodeAnalysis;
+using JetBrains.Annotations;
+
+namespace Nuke.Core.BuildServers
+{
+    [PublicAPI]
+    [SuppressMessage("ReSharper", "InconsistentNaming")]
+
+    public enum TravisEventType
+
+    {
+        push,
+        pull_request,
+        api,
+        cron
+    }
+}

source/Nuke.Core/HostType.cs

@@ -15,6 +15,7 @@ public enum HostType
         Bitrise,
         AppVeyor,
         Jenkins,
+        Travis,
         GitLab
     }
 }