@Inject
    public DefaultToolchainSpec() {
        getVendor().convention(getConventionVendor());
        getImplementation().convention(getConventionImplementation());
    }
    @Override
    public JavaToolchainSpecInternal.Key toKey() {
        return new Key(getLanguageVersion().getOrNull(), getVendor().getOrNull(), getImplementation().getOrNull());
    }

    @Override
    public boolean isConfigured() {

// end::custom-dependencies-type[]

// tag::custom-dependencies-scopes[]
    /**
     * Dependency scope called "implementation"
     */
    DependencyCollector getImplementation();
// end::custom-dependencies-scopes[]

        ClassImplementationSnapshot currentImplementation = Cast.uncheckedNonnullCast(thisExecution.getImplementation());
        ClassImplementationSnapshot previousImplementation = Cast.uncheckedNonnullCast(lastExecution.getImplementation());
        ImmutableList<ImplementationSnapshot> currentAdditionalImplementations = Cast.uncheckedNonnullCast(thisExecution.getAdditionalImplementations());

// tag::wire-dependencies[]
        project.getConfigurations().dependencyScope("exampleImplementation", conf -> {
            conf.fromDependencyCollector(example.getDependencies().getImplementation());
        });
// end::wire-dependencies[]
    }

        def spec = TestUtil.objectFactory().newInstance(DefaultToolchainSpec)
        spec.getLanguageVersion().set(JavaLanguageVersion.of(javaVersion.getMajorVersion()))
        spec.getVendor().set(vendor)
        spec.getImplementation().set(implementation)

        then:
        new JvmInstallationMetadataMatcher(spec).test(metadata)

        where:

        this.jvmImplementation = jvmImplementation;
    }

    public JvmInstallationMetadataMatcher(JavaToolchainSpec spec) {
        this(spec.getLanguageVersion().get(), spec.getVendor().get(), spec.getImplementation().get());
    }

    @Override
    public boolean test(JvmInstallationMetadata metadata) {
        Predicate<JvmInstallationMetadata> predicate = languagePredicate().and(vendorPredicate()).and(this::implementationTest);

        Class<?> workType = workClass.get();
        TypeValidationContext workValidationContext = validationContext.forType(workType, true);
        validateImplementation(workValidationContext, beforeExecutionState.getImplementation(), "Implementation of ", work);
        beforeExecutionState.getAdditionalImplementations()