}
        }

        private void writeVariantConstraints(ImmutableList<? extends ComponentVariant.DependencyConstraint> constraints) throws IOException {
            encoder.writeSmallInt(constraints.size());
            for (ComponentVariant.DependencyConstraint constraint : constraints) {

        """
    }

    private static final String ERROR_MESSAGE_PROVIDER = "Providers of type 'java.lang.String' are not supported. Only Provider<Dependency> and Provider<DependencyConstraint> are supported. Try using the Provider#map method to convert to a supported type.";

    def "cannot add non-Dependency providers to the dependency collector (fails at runtime)"() {
        given:

import org.gradle.api.artifacts.ConfigurablePublishArtifact
import org.gradle.api.artifacts.ConfigurationContainer
import org.gradle.api.artifacts.Dependency
import org.gradle.api.artifacts.DependencyConstraint
import org.gradle.api.artifacts.ExternalModuleDependency
import org.gradle.api.artifacts.ModuleDependency
import org.gradle.api.artifacts.PublishArtifact
import org.gradle.api.artifacts.dsl.ArtifactHandler

                dependsOn('org:other:1.0')
            }
        }
        def bomDep = mavenHttpRepo.module('org', 'xml', '2.0')
        mavenHttpRepo.module('bom', 'bom', '1.0').dependencyConstraint(bomDep).hasPackaging('pom').publish()

        given:
        buildFile << """
            configurations {
                conf.resolutionStrategy.force 'org:other:1.0'
            }

    def 'can publish java library with a #config dependency on a published BOM platform"'() {
        given:
        javaLibrary(mavenRepo.module("org.test", "bom", "1.0")).hasPackaging('pom').dependencyConstraint(mavenRepo.module('org.test', 'bar', '1.1')).withModuleMetadata().publish()
        javaLibrary(mavenRepo.module("org.test", "bar", "1.0")).withModuleMetadata().publish()

     * @param dependencies The dependency constraints
     */
    public BuildScriptBuilder implementationDependencyConstraint(@Nullable String comment, BuildInitDependency... dependencies) {
        dependencies().dependencyConstraint("implementation", comment, dependencies);
        return this;
    }

    /**
     * Adds one or more external test implementation dependencies.
     *

        def fooModule = mavenRepo.module("org", "foo", "1.0")
        mavenRepo.module("org", "platform", "1.0")
            .asGradlePlatform()
            .dependencyConstraint(fooModule)
            .publish()

        createDirs("lib")
        settingsFile << """
            include 'lib'
        """

        file('lib/build.gradle') << """

        given:
        def leaf = mavenRepo.module("org", "leaf", "1.0").publish()
        def bom = mavenRepo.module('org', 'bom', '1.0')
        bom.packaging = 'pom'
        bom.dependencyConstraint(leaf)
        bom.publish()

        buildFile << """
            apply plugin: 'java-library'

            repositories {
               maven { url "${mavenRepo.uri}" }
            }

Class <org.gradle.api.publish.internal.metadata.ModuleMetadataSpec$DependencyConstraint> is not annotated (directly or via its package) with @org.gradle.api.NonNullApi in (ModuleMetadataSpec.java:0)