buildB.rootProject.name == "buildB"
        buildB.projects.size() == 4
        buildB.includedBuilds.size() == 1

        def buildC = buildB.includedBuilds[0]
        buildC.buildIdentifier.rootDir == buildCDir
        buildC.rootProject.name == "buildC"
        buildC.projects.size() == 1
        buildC.includedBuilds.empty
    }

    @TargetGradleVersion(">=4.10")

### Build tree state

"Build tree" is another name for the build definition.
The "build tree state" holds the state for the entire build definition for a single build execution within a session.

The build tree state is managed by the `BuildTreeState` class.
An instance is created at the start of a build execution and discarded at the end of the execution.

### Build state

        task build1(type:BuildSrcTask) {
            doLast {
                ${server.callFromBuild('build1')}
            }
        }

        task build2(type:BuildSrcTask) {
            doLast {
                ${server.callFromBuild('build2')}
            }
        }
        """

        server.expectConcurrent("build1", "build2")

        when:

        // Block until second build has produced blue things
        def build2 = executer.withTasks("redThings", "blueThings", "block2").start()
        block2.waitForAllPendingCalls()

        // Finish up first build while second build is still running
        block1.releaseAll()
        def result1 = build1.waitForFinish()

        block2.releaseAll()
        def result2 = build2.waitForFinish()

        then:

        executer.withTasks("a", "b", "block2")
        def build2 = executer.start()
        block2.waitForAllPendingCalls()

        // Finish up build 1 and 2
        block1.releaseAll() // finish build 1 while build 2 is still running
        def result1 = build1.waitForFinish()
        block2.releaseAll()
        def result2 = build2.waitForFinish()

        then:

    @Shared
    def project = TestUtil.builder(temporaryFolder).withName("root").build()
    @Shared
    def child1 = ProjectBuilder.builder().withName("child1").withParent(project).build()
    @Shared
    def child2 = ProjectBuilder.builder().withName("child2").withParent(project).build()

    def "builds model"() {
        def builder = new GradleBuildBuilder(project.services.get(BuildStateRegistry))

        def build1 = executer.start()
        block1.waitForAllPendingCalls()

        // Start build 2 then wait until it has run both 'a' and 'b'.
        executer.withTasks("a", "b", "block2")
        executer.withArgument("--info")
        def build2 = executer.start()
        block2.waitForAllPendingCalls()

        // Finish up build 1 and 2
        block1.releaseAll() // finish build 1 while build 2 is still running

        // Finish up build 1 and 2
        block1.releaseAll() // finish build 1 while build 2 is still running
        build1.waitForFinish()
        block2.releaseAll()
        build2.waitForFinish()
    }

        failure.assertThatCause(Matchers.containsText("Multiple build operations failed"));
    }

    // This is the current behavior:
    // We need to make sure that the build operation ids of nested builds started by a GradleBuild task do not overlap.

                    commits: ['abcdef']
                ]
            ],
            totalTime: [
                [
                    label: 'build1',
                    data: [[0, 1]]
                ],
                [
                    label: 'build2',
                    data: [[0, 2]]
                ]
            ]
        ]
    }

    def 'can calculate background color'() {