return createComponent([], [dependency])
    }

    def componentWithArtifact(def artifact) {
        return createComponent([artifact], [])
    }

    def createComponent(def artifacts, def dependencies) {
        return createComponent(artifacts, dependencies, 'runtime')
    }

        return createArtifact(artifactFile)
    }

    def componentWithDependency(ModuleDependency dependency) {
        return createComponent([], [dependency])
    }

    def componentWithArtifact(def artifact) {
        return createComponent([artifact], [])
    }

    def createComponent(def artifacts, def dependencies) {
        def variant = Stub(UsageContext) {
            getName() >> 'runtime'

        given:
        componentIdentifierFactory.createProjectComponentSelector(_) >> Mock(ProjectComponentSelector)
        def fromComponent = createComponent(from)
        def toComponent = createComponent(to)

        when:
        substitutions.substitute(fromComponent).using(toComponent)

        then:
        substitutions.rulesMayAddProjectDependency() == result

        }
    }

    def "plugin can create component"() {
        when:
        buildFile << """
        class SomeComponentPlugin extends RuleSource {
            @Mutate
            void createComponent(ComponentSpecContainer specs) {
                specs.create("someCustomComponent", CustomComponent)
            }
        }
        apply plugin: SomeComponentPlugin
        """
        then: