*/
public class MavenExecutionPlan implements Iterable<ExecutionPlanItem> {

    /*
      At the moment, this class is totally immutable, and this is in line with thoughts about the
      pre-calculated execution plan that stays the same during the execution.

      If deciding to add mutable state to this class, it should be at least considered to
      separate this into a separate mutable structure.

    */

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+ Update your JIRA ticket and include a link to the pull request in the ticket.

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Making Trivial Changes
----------------------

For changes of a trivial nature to comments and documentation, it is not always

            if (plugin.isExtensions() && !artifacts.isEmpty()) {
                // ignore plugin descriptor parsing errors at this point
                // these errors will reported during calculation of project build execution plan
                try {
                    pluginDescriptor = extractPluginDescriptor(artifacts.get(0), plugin);
                } catch (PluginDescriptorParsingException | InvalidPluginDescriptorException e) {

        MavenExecutionPlan plan = LifecycleExecutionPlanCalculatorStub.getProjectAExecutionPlan();
        final Set<Plugin> unSafePlugins = plan.getNonThreadSafePlugins();
        // There is only a single threadsafe plugin here...
        assertEquals(plan.size() - 1, unSafePlugins.size());
    }

    @Test
    void testFindLastWhenFirst() throws Exception {

import org.apache.maven.project.MavenProject;

/**
 * Lifecycle mapping delegate component interface. Calculates project build execution plan given {@link Lifecycle} and
 * lifecycle phase. Standard lifecycles use plugin execution {@code <phase>} or mojo default lifecycle phase to
 * calculate the execution plan, but custom lifecycles can use alternative mapping strategies.
 */
@Named(DefaultLifecycleMappingDelegate.HINT)
@Singleton

        int result = 0;
        for (ProjectSegment projectBuild : projectBuildList) {
            MavenExecutionPlan plan = calculateExecutionPlan(
                    projectBuild.getSession(),
                    projectBuild.getProject(),
                    projectBuild.getTaskSegment().getTasks());
            result += plan.size();
        }
        return result;
    }

 * lifecycle at all, in which case we wouldn't be needing this class at all ( and
 * ProjectBuildList.getByTaskSegments). Or maybe they should be introduced in the calculation
 * of the execution plan instead, which seems much nicer.
 * </p>
 * <p>
 * Additionally this class contains a clone of the MavenSession, which is *only* needed
 * because it has as notion of a "current" project.
 * </p>

    void testObserveExecution() throws Exception {
        PhaseRecorder phaseRecorder = new PhaseRecorder(ProjectDependencyGraphStub.A);
        MavenExecutionPlan plan = LifecycleExecutionPlanCalculatorStub.getProjectAExecutionPlan();
        final List<MojoExecution> executions = plan.getMojoExecutions();

        final MojoExecution mojoExecution1 = executions.get(0);
        final MojoExecution mojoExecution2 = executions.get(1);

import org.apache.maven.project.MavenProject;

/**
 * Lifecycle mapping delegate component interface. Calculates project build execution plan given {@link Lifecycle} and
 * lifecycle phase. Standard lifecycles use plugin execution {@code <phase>} or mojo default lifecycle phase to
 * calculate the execution plan, but custom lifecycles can use alternative mapping strategies.
 * <p>

        logger.info(s);
    }

    public void debugReactorPlan(ProjectBuildList projectBuilds) {
        if (!logger.isDebugEnabled()) {
            return;
        }

        logger.debug("=== REACTOR BUILD PLAN ================================================");

        for (Iterator<ProjectSegment> it = projectBuilds.iterator(); it.hasNext(); ) {
            ProjectSegment projectBuild = it.next();