name: Feature request
description: File a proposal for new feature, improvement
labels: ["enhancement"]

body:
  - type: markdown
    attributes:
      value: |
        Thanks for taking the time to fill out this new feature, improvement proposal.

  - type: textarea
    id: message
    attributes:
      label: New feature, improvement proposal
    validations:

 */
package org.apache.maven.api.feature;

import java.util.Map;
import java.util.Properties;

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

/**
 * Centralized class for Maven Core feature information.
 * Features configured are supposed to be final in a given maven session.
 *
 * @since 4.0.0
 */
public final class Features {

    private Features() {}

    testers.add(MultisetIteratorTester.class);
    testers.add(MultisetSerializationTester.class);
    return testers;
  }

  private static Set<Feature<?>> computeEntrySetFeatures(Set<Feature<?>> features) {
    Set<Feature<?>> derivedFeatures = new HashSet<>(features);
    derivedFeatures.remove(CollectionFeature.GENERAL_PURPOSE);
    derivedFeatures.remove(CollectionFeature.SUPPORTS_ADD);

import com.google.common.collect.testing.DerivedCollectionGenerators.MapValueCollectionGenerator;
import com.google.common.collect.testing.features.CollectionFeature;
import com.google.common.collect.testing.features.CollectionSize;
import com.google.common.collect.testing.features.Feature;
import com.google.common.collect.testing.features.MapFeature;
import com.google.common.collect.testing.testers.MapClearTester;

import com.google.common.collect.testing.TestSubjectGenerator;
import com.google.common.collect.testing.features.CollectionFeature;
import com.google.common.collect.testing.features.CollectionSize;
import com.google.common.collect.testing.features.Feature;
import com.google.common.collect.testing.features.ListFeature;
import com.google.common.collect.testing.features.MapFeature;
import com.google.common.testing.SerializableTester;
import java.util.ArrayList;

			if !ok {
				t.Errorf("package %s: missing feature %q", fi.Name(), feature)
			}
			delete(w.features, feature)
		}

		for _, feature := range w.Features() {
			t.Errorf("package %s: extra feature not in golden file: %q", fi.Name(), feature)
		}
	}
}

func TestCompareAPI(t *testing.T) {
	if *flagCheck {
		// not worth repeating in -check
		t.Skip("skipping with -check set")
	}

	tests := []struct {

    testers.add(MultisetIteratorTester.class);
    testers.add(MultisetSerializationTester.class);
    return testers;
  }

  private static Set<Feature<?>> computeEntrySetFeatures(Set<Feature<?>> features) {
    Set<Feature<?>> derivedFeatures = new HashSet<>(features);
    derivedFeatures.remove(CollectionFeature.GENERAL_PURPOSE);
    derivedFeatures.remove(CollectionFeature.SUPPORTS_ADD);

import com.google.common.collect.testing.TestListGenerator;
import com.google.common.collect.testing.features.CollectionFeature;
import com.google.common.collect.testing.features.CollectionSize;
import com.google.common.collect.testing.features.Feature;
import com.google.common.collect.testing.features.ListFeature;
import java.util.Collections;
import java.util.EnumSet;
import java.util.List;
import java.util.Map.Entry;

@GwtCompatible
public class ConflictingRequirementsException extends Exception {
  private final Set<Feature<?>> conflicts;
  private final Object source;

  public ConflictingRequirementsException(
      String message, Set<Feature<?>> conflicts, Object source) {
    super(message);
    this.conflicts = conflicts;
    this.source = source;
  }

  public Set<Feature<?>> getConflicts() {
    return conflicts;
  }

  public Object getSource() {

    // Copy this set, so we can modify it.
    Set<Feature<?>> features = copyToSet(getFeatures());
    @SuppressWarnings("rawtypes") // class literals
    List<Class<? extends AbstractTester>> testers = getTesters();

    logger.fine(" Testing: " + name);

    // Split out all the specified sizes.
    Set<Feature<?>> sizesToTest = Helpers.<Feature<?>>copyToSet(CollectionSize.values());
    sizesToTest.retainAll(features);