fun addSystemPropertyToFingerprint(key: String, value: Any?, consumer: String? = null) {
        if (isSystemPropertyMutated(key)) {
            // Mutated values of the system properties are not part of the fingerprint, as their value is
            // set at the configuration time. Everything that reads a mutated property value should be saved
            // as a fixed value.
            return
        }
        val propertyValue =

            }
        }
        registry.configure(ModelActionRole.Mutate) {
            it.path("b").descriptor("b-mutate").action { Bean b ->
                b.value = "b-mutate"
            }
        }
        registry.configure(ModelActionRole.Mutate) {
            it.path("a").descriptor("a-mutate").action { Bean a ->
                a.value = "a-mutate"
            }
        }

     */
    protected abstract FileSystemNode withIncompleteChildren();

    /**
     * Returns an updated node with an updated list of children.
     *
     * Caller must ensure the child list is not be mutated as the method
     * doesn't make a defensive copy.
     */
    protected abstract FileSystemNode withIncompleteChildren(ChildMap<? extends FileSystemNode> newChildren);

    /**

 * equals}, {@code hashCode} and {@code compareTo} because instances are expected to be mutated, and
 * so are not useful as collection keys.
 *
 * <p>jsr166e note: This class is targeted to be placed in java.util.concurrent.atomic.
 *
 * @since 1.8
 * @author Doug Lea
 */
@GwtCompatible(emulated = true)
@ElementTypesAreNonnullByDefault

// no data should be written to the directory, and so the path values of
// LocalDir, UploadDir, etc. must not matter.
//
// Default is a global for convenience and testing, but should not be mutated
// outside of tests.
//
// TODO(rfindley): it would be nice to completely eliminate this global state,
// or at least push it in the golang.org/x/telemetry package
var Default Dir

	if info == nil {
		info = new(Info)
	}

	// Note: clients may call NewChecker with the Unsafe package, which is
	// globally shared and must not be mutated. Therefore NewChecker must not
	// mutate *pkg.
	//
	// (previously, pkg.goVersion was mutated here: go.dev/issue/61212)

	return &Checker{
		conf:    conf,
		ctxt:    conf.Context,
		pkg:     pkg,
		Info:    info,

        )

        def fixture = spec.createFixtureFor(this, systemProp)
        fixture.setup()

        settingsFile << "System.setProperty('$systemProp', 'mutated value')\n"

        when:
        System.clearProperty(systemProp)
        configurationCacheRun fixture.task

        then:

 * equals}, {@code hashCode} and {@code compareTo} because instances are expected to be mutated, and
 * so are not useful as collection keys.
 *
 * <p>jsr166e note: This class is targeted to be placed in java.util.concurrent.atomic.
 *
 * @since 1.8
 * @author Doug Lea
 */
@GwtCompatible(emulated = true)
@ElementTypesAreNonnullByDefault

        when:
        configurationCacheRun()

        then:
        configurationCache.assertStateStored()
        outputContains("ValueSource result = Hello, world")
    }

    def "value source can read mutated system property inputs at configuration time"() {
        given:
        def configurationCache = newConfigurationCacheFixture()
        buildFile("""
        import org.gradle.api.provider.*

 * higher space consumption.
 *
 * <p>This class extends {@link Number}, but does not define methods such as {@code
 * equals}, {@code hashCode} and {@code compareTo} because instances are expected to be mutated, and
 * so are not useful as collection keys.
 *
 * <p>jsr166e note: This class is targeted to be placed in java.util.concurrent.atomic.
 *
 * @since 1.8
 * @author Doug Lea
 */