import org.apache.maven.api.annotations.Nullable;

import static org.apache.maven.api.services.BaseRequest.nonNull;

/**
 * A Source specific to load POMs.  The {@link #resolve(ModelLocator, String)} method
 * will be used to find POMs for children modules.
 *
 * @since 4.0.0
 */
public interface ModelSource extends Source {

    interface ModelLocator {
        /**

         * unique within a single POM. Upon multiple declarations, 2.x just kept the last one but retained the order of
         * the first occurrence. So when we're in lenient/compat mode, we have to deal with such broken POMs and mimic
         * the way 2.x works. When we're in strict mode, the removal of duplicates just saves other merging steps from
         * aftereffects and bogus error messages.
         */

    }

    // Some better conventions for the test poms needs to be created and each of these tests
    // that represent a verification of a specification item needs to be a couple lines at most.
    // The expressions help a lot, but we need a clean to pick up a directory of POMs, automatically load

        return project == null ? null : project.getModel().getDelegate();
    }

    //
    // Implementation
    //

    private File findArtifact(MavenProject project, Artifact artifact) {
        // POMs are always returned from the file system
        if ("pom".equals(artifact.getExtension())) {
            return project.getFile();
        }

        // First check in the project local repository

        }
    }

    /**
     * Gets the identifiers of all profiles that contributed to this project's effective model. This includes active
     * profiles from the project's POM and all its parent POMs as well as from external sources like the
     * {@code settings.xml}. The profile identifiers are grouped by the identifier of their source, e.g.

     * @param files List of POM files.
     * @param request The {@link MavenExecutionRequest}
     * @return A list of projects that have been found in the specified POM files.
     * @throws ProjectBuildingException In case the POMs are not used.
     */
    List<MavenProject> selectProjects(List<File> files, MavenExecutionRequest request) throws ProjectBuildingException;

            org.apache.maven.api.settings.InputLocation location) {
        if (location != null) {
            org.apache.maven.api.settings.InputSource source = location.getSource();
            Map<Object, InputLocation> locs = location.getLocations().entrySet().stream()
                    .collect(Collectors.toMap(Map.Entry::getKey, e -> toLocation(e.getValue())));
            return new org.apache.maven.api.model.InputLocation(

 * <p>
 * A note to the reader;
 * </p>
 * <p>
 * There are several issues/discussions regarding how "aggregator" plugins should be handled.
 * Read for instance http://docs.codehaus.org/display/MAVEN/Deterministic+Lifecycle+Planning
 * </p>
 * <p>
 * In their current implementation they are "bolted" onto the lifecycle by separating them

 *
 * @since 4.0.0
 */
@Experimental
@Immutable
public interface ModelBuilderRequest {

    /**
     * Denotes minimal validation of POMs. This validation level is meant for processing of POMs from repositories
     * during metadata retrieval.
     */
    int VALIDATION_LEVEL_MINIMAL = 0;

    /**

            node.getArtifact().setFile(artifact.getFile());
        }
    }

    /**
     * Check if the artifactScope needs to be updated. <a
     * href="http://docs.codehaus.org/x/IGU#DependencyMediationandConflictResolution-Scoperesolution">More info</a>.
     *
     * @param farthest farthest resolution node
     * @param nearest nearest resolution node
     * @param listeners