newComparable("0-x");
        newComparable("0.rc");
        newComparable("0-1");

        ComparableVersion version = new ComparableVersion("0.x");
        assertEquals("x", version.getCanonical());
        ComparableVersion version2 = new ComparableVersion("0.2");
        assertEquals("0.2", version2.getCanonical());
    }

    /**
     * Test <a href="https://issues.apache.org/jira/browse/MNG-5568">MNG-5568</a> edge case

                versioning.release(recessive.getVersioning().getRelease());
            }

            Collection<String> versions =
                    new LinkedHashSet<>(recessive.getVersioning().getVersions());
            versions.addAll(original.getVersions());
            versioning.versions(new ArrayList<>(versions));
        }

        metadata = metadata.withVersioning(versioning.build());

        // just carry-on as-is

                                        if (versions == null) {
                                            versions = source.retrieveAvailableVersions(metadataRequest);
                                            artifact.setAvailableVersions(versions);
                                        }

                                        Collections.sort(versions);

    public List<String> findVersions(Artifact artifact) {
        Collection<String> versions = new LinkedHashSet<>();

        if (buildReactor != null) {
            versions.addAll(buildReactor.findVersions(artifact));
        }

        if (ideWorkspace != null) {
            versions.addAll(ideWorkspace.findVersions(artifact));
        }

        versions.addAll(userLocalArtifactRepository.findVersions(artifact));

                () -> newModelResolver().resolveModel(parent.getDelegate(), new AtomicReference<>()),
                "Expected 'UnresolvableModelException' not thrown.");
        assertEquals("No versions matched the requested parent version range '[2.0,2.1)'", e.getMessage());
    }

    @Test
    void testResolveParentThrowsUnresolvableModelExceptionWhenUsingRangesWithoutUpperBound() throws Exception {

        }

        for (String key : versions.keySet()) {
            if (versions.get(key) == null && managedVersions.get(key) == null) {
                InputLocation location = plugins.get(key).getLocation("");
                problems.add(
                        Severity.WARNING,
                        ModelProblem.Version.V20,
                        "'build.plugins.plugin.version' for " + key + " is missing.",

import org.apache.maven.model.Plugin;
import org.apache.maven.model.PluginManagement;
import org.apache.maven.plugin.version.DefaultPluginVersionRequest;
import org.apache.maven.plugin.version.PluginVersionRequest;
import org.apache.maven.plugin.version.PluginVersionResolutionException;
import org.apache.maven.plugin.version.PluginVersionResolver;
import org.apache.maven.project.MavenProject;

/**

import org.eclipse.aether.artifact.Artifact;
import org.eclipse.aether.graph.Dependency;
import org.eclipse.aether.resolution.ArtifactDescriptorResult;

/**
 * Detects mixed Maven versions in plugins.
 *
 * @since 3.9.2
 */
@Singleton
@Named
class MavenMixedDependenciesValidator extends AbstractMavenPluginDependenciesValidator {

    @Inject

 */
@Named(VersionsMetadataGeneratorFactory.NAME)
@Singleton
public class VersionsMetadataGeneratorFactory implements MetadataGeneratorFactory {
    public static final String NAME = "versions";

    @Override
    public MetadataGenerator newInstance(RepositorySystemSession session, InstallRequest request) {
        return new VersionsMetadataGenerator(session, request);
    }

    @Override

import org.apache.maven.artifact.versioning.ArtifactVersion;
import org.apache.maven.repository.legacy.metadata.MetadataResolutionRequest;

/**
 * Provides some metadata operations, like querying the remote repository for a list of versions available for an
 * artifact - deprecated
 */
@Deprecated
public interface ArtifactMetadataSource extends org.apache.maven.repository.legacy.metadata.ArtifactMetadataSource {