Merge pull request #245 from jakobk/jenkins_22009

JENKINS-22009 Git Polling Keeps Detecting Changes When Variables in refspec

src/main/java/hudson/plugins/git/util/GitUtils.java

@@ -15,7 +15,6 @@
 import org.eclipse.jgit.lib.Repository;
 import org.eclipse.jgit.revwalk.RevCommit;
 import org.eclipse.jgit.revwalk.RevWalk;
-import org.eclipse.jgit.revwalk.filter.RevFilter;
 import org.jenkinsci.plugins.gitclient.GitClient;
 import org.jenkinsci.plugins.gitclient.RepositoryCallback;
 
@@ -202,7 +201,15 @@ public static EnvVars getPollEnvironment(AbstractProject p, FilePath ws, Launche
         StreamBuildListener buildListener = new StreamBuildListener((OutputStream)listener.getLogger());
         AbstractBuild b = p.getLastBuild();
 
-        if (reuseLastBuildEnv && b != null) {
+        if (b == null) {
+            // If there is no last build, we need to trigger a new build anyway, and
+            // GitSCM.compareRemoteRevisionWithImpl() will short-circuit and never call this code
+            // ("No previous build, so forcing an initial build.").
+            throw new IllegalArgumentException("Last build must not be null. If there really is no last build, " +
+                    "a new build should be triggered without polling the SCM.");
+        }
+
+        if (reuseLastBuildEnv) {
             Node lastBuiltOn = b.getBuiltOn();
 
             if (lastBuiltOn != null) {
@@ -218,11 +225,6 @@ public static EnvVars getPollEnvironment(AbstractProject p, FilePath ws, Launche
             }
 
             p.getScm().buildEnvVars(b,env);
-
-            if (lastBuiltOn != null) {
-
-            }
-
         } else {
             env = new EnvVars(System.getenv());
         }
@@ -231,7 +233,7 @@ public static EnvVars getPollEnvironment(AbstractProject p, FilePath ws, Launche
         if(rootUrl!=null) {
             env.put("HUDSON_URL", rootUrl); // Legacy.
             env.put("JENKINS_URL", rootUrl);
-            if( b != null) env.put("BUILD_URL", rootUrl+b.getUrl());
+            env.put("BUILD_URL", rootUrl+b.getUrl());
             env.put("JOB_URL", rootUrl+p.getUrl());
         }
 
@@ -251,11 +253,27 @@ public static EnvVars getPollEnvironment(AbstractProject p, FilePath ws, Launche
             }
         }
 
+        // add env contributing actions' values from last build to environment - fixes JENKINS-22009
+        addEnvironmentContributingActionsValues(env, b);
+
         EnvVars.resolve(env);
 
         return env;
     }
 
+    private static void addEnvironmentContributingActionsValues(EnvVars env, AbstractBuild b) {
+        List<? extends Action> buildActions = b.getAllActions();
+        if (buildActions != null) {
+            for (Action action : buildActions) {
+                // most importantly, ParametersAction will be processed here (for parameterized builds)
+                if (action instanceof EnvironmentContributingAction) {
+                    EnvironmentContributingAction envAction = (EnvironmentContributingAction) action;
+                    envAction.buildEnvVars(b, env);
+                }
+            }
+        }
+    }
+
     public static String[] fixupNames(String[] names, String[] urls) {
         String[] returnNames = new String[urls.length];
         Set<String> usedNames = new HashSet<String>();

src/test/java/hudson/plugins/git/GitSCMTest.java

@@ -1,7 +1,8 @@
 package hudson.plugins.git;
 
+import com.google.common.base.Function;
+import com.google.common.collect.Collections2;
 import com.google.common.collect.Lists;
-
 import hudson.EnvVars;
 import hudson.FilePath;
 import hudson.matrix.Axis;
@@ -10,16 +11,9 @@
 import hudson.matrix.MatrixProject;
 import hudson.model.*;
 import hudson.plugins.git.GitSCM.BuildChooserContextImpl;
-import hudson.plugins.git.browser.GitRepositoryBrowser;
-import hudson.plugins.git.browser.GithubWeb;
+import hudson.plugins.git.GitSCM.DescriptorImpl;
 import hudson.plugins.git.extensions.GitSCMExtension;
-import hudson.plugins.git.extensions.impl.AuthorInChangelog;
-import hudson.plugins.git.extensions.impl.CleanBeforeCheckout;
-import hudson.plugins.git.extensions.impl.LocalBranch;
-import hudson.plugins.git.extensions.impl.PreBuildMerge;
-import hudson.plugins.git.extensions.impl.RelativeTargetDirectory;
-import hudson.plugins.git.extensions.impl.SparseCheckoutPath;
-import hudson.plugins.git.extensions.impl.SparseCheckoutPaths;
+import hudson.plugins.git.extensions.impl.*;
 import hudson.plugins.git.util.BuildChooserContext;
 import hudson.plugins.git.util.BuildChooserContext.ContextCallable;
 import hudson.plugins.parameterizedtrigger.BuildTrigger;
@@ -30,15 +24,9 @@
 import hudson.scm.PollingResult;
 import hudson.slaves.DumbSlave;
 import hudson.slaves.EnvironmentVariablesNodeProperty.Entry;
-import hudson.plugins.git.GitSCM.DescriptorImpl;
 import hudson.tools.ToolProperty;
 import hudson.util.IOException2;
-
-import com.google.common.base.Function;
-import com.google.common.collect.Collections2;
-
 import hudson.util.StreamTaskListener;
-
 import org.apache.commons.io.FileUtils;
 import org.eclipse.jgit.lib.Constants;
 import org.eclipse.jgit.lib.PersonIdent;
@@ -1271,6 +1259,32 @@ public void testInitSparseCheckoutOverSlave() throws Exception {
         assertFalse(build1.getWorkspace().child(commitFile1).exists());
     }
 
+    /**
+     * Test for JENKINS-22009.
+     *
+     * @throws Exception
+     */
+    public void testPolling_environmentValueInBranchSpec() throws Exception {
+        // create parameterized project with environment value in branch specification
+        FreeStyleProject project = createFreeStyleProject();
+        GitSCM scm = new GitSCM(
+                createRemoteRepositories(),
+                Collections.singletonList(new BranchSpec("${MY_BRANCH}")),
+                false, Collections.<SubmoduleConfig>emptyList(),
+                null, null,
+                Collections.<GitSCMExtension>emptyList());
+        project.setScm(scm);
+        project.addProperty(new ParametersDefinitionProperty(new StringParameterDefinition("MY_BRANCH", "master")));
+
+        // commit something in order to create an initial base version in git
+        commit("toto/commitFile1", johnDoe, "Commit number 1");
+
+        // build the project
+        build(project, Result.SUCCESS);
+
+        assertFalse("No changes to git since last build, thus no new build is expected", project.poll(listener).hasChanges());
+    }
+
     private void setupJGit(GitSCM git) {
         git.gitTool="jgit";
         jenkins.getDescriptorByType(GitTool.DescriptorImpl.class).setInstallations(new JGitTool(Collections.<ToolProperty<?>>emptyList()));