Add test unit for JENKINS-22641

test/src/test/java/hudson/util/ProcessTreeKillerTest.java

 package hudson.util;
 
-import hudson.model.FreeStyleProject;
+import hudson.Functions;
 import hudson.model.FreeStyleBuild;
+import hudson.model.FreeStyleProject;
 import hudson.tasks.Maven;
-
-import org.easymock.EasyMock;
+import hudson.tasks.Shell;
+import org.jvnet.hudson.test.Bug;
 import org.jvnet.hudson.test.ExtractResourceSCM;
 import org.jvnet.hudson.test.HudsonTestCase;
-import org.kohsuke.stapler.StaplerRequest;
-import org.kohsuke.stapler.StaplerResponse;
 
 public class ProcessTreeKillerTest extends HudsonTestCase {
 
@@ -34,4 +33,25 @@ public class ProcessTreeKillerTest extends HudsonTestCase {
 
 	}
 
+    @Bug(22641)
+    public void testProcessProperlyKilledUnix() throws Exception {
+        ProcessTree.enabled = true;
+        if (Functions.isWindows()) return; // This test does not involve windows.
+
+        FreeStyleProject sleepProject = createFreeStyleProject();
+        FreeStyleProject processJob = createFreeStyleProject();
+
+        sleepProject.getBuildersList().add(new Shell("nohup sleep 100000 &"));
+
+        assertBuildStatusSuccess(sleepProject.scheduleBuild2(0).get());
+
+        processJob.getBuildersList().add(new Shell("ps -ef | grep sleep"));
+
+        String log = processJob.scheduleBuild2(0).get().getLog();
+
+        System.err.println("LOGS: " + log);
+
+        assertFalse("Did not properly kill task", log.contains("sleep 100000"));
+    }
+
 }