mavenExecutionRequest.setDegreeOfConcurrency(1);
        final MavenSession session = new MavenSession(null, null, mavenExecutionRequest, defaultMavenExecutionResult);
        final ProjectDependencyGraphStub dependencyGraphStub = new ProjectDependencyGraphStub();
        session.setProjectDependencyGraph(dependencyGraphStub);
        session.setProjects(dependencyGraphStub.getSortedProjects());
        return session;
    }

    @Test
    void testResolveBuildPlan() throws Exception {
        MavenSession original = ProjectDependencyGraphStub.getMavenSession();

        final TaskSegment taskSegment1 = new TaskSegment(false);
        final MavenSession session1 = original.clone();
        session1.setCurrentProject(ProjectDependencyGraphStub.A);

        final BuilderCommon builderCommon = getBuilderCommon(logger);
        final MavenExecutionPlan plan =

import org.apache.maven.lifecycle.internal.stub.ProjectDependencyGraphStub;
import org.apache.maven.project.MavenProject;
import org.junit.jupiter.api.Test;

import static org.junit.jupiter.api.Assertions.assertEquals;

class ConcurrencyDependencyGraphTest {

    @Test
    void testGraph() throws Exception {

        ProjectBuildList projectBuildList =

import static org.apache.maven.lifecycle.internal.stub.ProjectDependencyGraphStub.A;
import static org.apache.maven.lifecycle.internal.stub.ProjectDependencyGraphStub.B;
import static org.apache.maven.lifecycle.internal.stub.ProjectDependencyGraphStub.C;
import static org.apache.maven.lifecycle.internal.stub.ProjectDependencyGraphStub.X;
import static org.apache.maven.lifecycle.internal.stub.ProjectDependencyGraphStub.Y;

/**
 * Tests the stub. Yeah, I know.
 *
 */
class ProjectDependencyGraphStubTest {
    ProjectDependencyGraphStub stub = new ProjectDependencyGraphStub();

    @Test
    void testADependencies() {
        final List<MavenProject> mavenProjects = stub.getUpstreamProjects(ProjectDependencyGraphStub.A, false);
        assertEquals(0, mavenProjects.size());
    }

    @Test
    void testBDependencies() {

        assertEquals(
                Arrays.asList(
                        ProjectDependencyGraphStub.A,
                        ProjectDependencyGraphStub.B,
                        ProjectDependencyGraphStub.C,
                        ProjectDependencyGraphStub.X,
                        ProjectDependencyGraphStub.Y,
                        ProjectDependencyGraphStub.Z),
                currentProjects);
    }

                    NoPluginFoundForPrefixException, LifecycleNotFoundException, PluginVersionResolutionException {
        if (project.equals(ProjectDependencyGraphStub.A)) {
            return getProjectAExecutionPlan();
        }
        if (project.equals(ProjectDependencyGraphStub.B)) {
            return getProjectBExecutionPlan();
        }
        // The remaining are basically "for future expansion"

import java.util.List;

import org.apache.maven.execution.MavenSession;
import org.apache.maven.lifecycle.internal.stub.LifecycleTaskSegmentCalculatorStub;
import org.apache.maven.lifecycle.internal.stub.ProjectDependencyGraphStub;
import org.junit.jupiter.api.Test;

import static org.junit.jupiter.api.Assertions.assertEquals;
import static org.junit.jupiter.api.Assertions.assertNotNull;

/**
 */

        final TaskSegment taskSegment1 = new TaskSegment(false, goalTask1, goalTask2);
        final MavenSession session1 = ProjectDependencyGraphStub.getMavenSession(ProjectDependencyGraphStub.A);

        MavenExecutionPlan executionPlan = lifecycleExecutionPlanCalculator.calculateExecutionPlan(
                session1, ProjectDependencyGraphStub.A, taskSegment1.getTasks());
        assertEquals(2, executionPlan.size());

        phaseRecorder.observeExecution(mojoExecution1);

        assertTrue(ProjectDependencyGraphStub.A.hasLifecyclePhase(mojoExecution1.getLifecyclePhase()));
        assertFalse(ProjectDependencyGraphStub.A.hasLifecyclePhase(mojoExecution2.getLifecyclePhase()));

        assertFalse(phaseRecorder.isDifferentPhase(mojoExecution1));
        assertTrue(phaseRecorder.isDifferentPhase(mojoExecution2));
    }