improve testParallelLimitConcurrency to do a basic test of the limit

The test testParallelLimitConcurrency now does a very basic test of the
concurrency limit by using a job which pauses for ten seconds and thus the
expected runtime of the flow can be tested based on the configured limit.

src/test/groovy/com/cloudbees/plugins/flow/DSLTestCase.groovy

@@ -1,8 +1,9 @@
 /*
  * The MIT License
  *
- * Copyright (c) 2013, CloudBees, Inc., Nicolas De Loof.
- *                     Cisco Systems, Inc., a California corporation
+ * Copyright (c) 2013-2015, CloudBees, Inc., Nicolas De Loof.
+ *                          Cisco Systems, Inc., a California corporation
+ *                          SAP SE
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -49,6 +50,7 @@ import hudson.model.BuildListener
 import hudson.tasks.Builder
 import com.cloudbees.plugin.flow.ConfigurableFailureBuilder
 import com.cloudbees.plugin.flow.BlockingBuilder
+import com.cloudbees.plugin.flow.SleepingBuilder
 import hudson.model.Job
 
 import static hudson.model.Result.UNSTABLE
@@ -67,6 +69,14 @@ abstract class DSLTestCase extends HudsonTestCase {
          return jobs
     }
 
+     def createSleepingJobs = { names ->
+         def jobs = []
+         names.each {
+             jobs.add(createSleepingJob(it))
+         }
+         return jobs
+    }
+
     def createFailJob = {String name, int failures = Integer.MAX_VALUE ->
         def job = createJob(name)
         job.getBuildersList().add(new ConfigurableFailureBuilder(failures));
@@ -85,6 +95,12 @@ abstract class DSLTestCase extends HudsonTestCase {
         return job
     }
 
+    def createSleepingJob = {String name, int seconds = 10 ->
+        def job = createJob(name)
+        job.getBuildersList().add(new SleepingBuilder(seconds));
+        return job
+    }
+
     def run = { script ->
         BuildFlow flow = new BuildFlow(Jenkins.instance, getName())
         flow.dsl = script

src/test/groovy/com/cloudbees/plugins/flow/ParallelTest.groovy

@@ -47,7 +47,7 @@ class ParallelTest extends DSLTestCase {
     }
 
     public void testParallelLimitConcurrency() {
-        def jobs = createJobs(["job1", "job2", "job3", "job4"])
+        def jobs = createSleepingJobs(["job1", "job2", "job3", "job4"])
         def flow = run("""
             parallel( 2,
                 { build("job1") },
@@ -57,6 +57,8 @@ class ParallelTest extends DSLTestCase {
             )
         """)
         assertAllSuccess(jobs)
+		assert flow.duration/1000 >= (5+10)*2
+		assert flow.duration/1000 <  (5+10)*3
         assert SUCCESS == flow.result
         println flow.jobsGraph.edgeSet()
     }

src/test/java/com/cloudbees/plugin/flow/SleepingBuilder.java

@@ -0,0 +1,73 @@
+/*
+ * The MIT License
+ *
+ * Copyright (c) 2013-2015, Cisco Systems, Inc., a California corporation
+ *                          SAP SE
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+package com.cloudbees.plugin.flow;
+
+import hudson.Extension;
+import hudson.Launcher;
+import hudson.model.AbstractBuild;
+import hudson.model.BuildListener;
+import hudson.model.Descriptor;
+import hudson.tasks.Builder;
+import net.sf.json.JSONObject;
+import org.kohsuke.stapler.StaplerRequest;
+
+import static hudson.model.Result.*;
+
+/**
+ * A Builder that will sleep for the specified number of seconds.
+ *
+ * @author: James Nord
+ */
+public class SleepingBuilder extends Builder {
+
+    public final int sleepSeconds;
+
+    SleepingBuilder(int sleepSeconds) {
+        this.sleepSeconds = sleepSeconds;
+    }
+
+    public boolean perform(AbstractBuild<?, ?> build, Launcher launcher, BuildListener listener) {
+        System.out.println("Sleeping Builder in build " + build.getFullDisplayName() + "starting");
+        try {
+            System.out.println("Sleeping Builder in build " + build.getFullDisplayName() + "waiting");
+            Thread.sleep(sleepSeconds * 1000);
+        } catch (InterruptedException ex) {
+            build.setResult(ABORTED);
+        }
+        System.out.println("Sleeping Builder in build " + build.getFullDisplayName() + " completing " + build.getResult());
+        return true;
+    }
+
+    @Extension
+    public static final class DescriptorImpl extends Descriptor<Builder> {
+        public String getDisplayName() {
+            return "Sleeping builder";
+        }
+
+        public SleepingBuilder newInstance(StaplerRequest req, JSONObject data) {
+            return new SleepingBuilder(10);
+        }
+    }
+}