src/main/java/org/apache/maven/shared/dependency/graph/internal/VerboseJavaScopeSelector.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
package org.apache.maven.shared.dependency.graph.internal;

import java.util.Arrays;
import java.util.Comparator;
import java.util.List;

import org.eclipse.aether.RepositoryException;
import org.eclipse.aether.util.graph.transformer.ConflictResolver.ConflictContext;
import org.eclipse.aether.util.graph.transformer.ConflictResolver.ScopeSelector;
import org.eclipse.aether.util.graph.transformer.JavaScopeSelector;

/**
 * A JavaScopeSelector that keeps track of reduced scopes.
 */
public class VerboseJavaScopeSelector extends ScopeSelector {
    public static final String REDUCED_SCOPE = "REDUCED_SCOPE";

    private final ScopeSelector scopeSelector = new JavaScopeSelector();

    @Override
    public void selectScope(ConflictContext context) throws RepositoryException {
        scopeSelector.selectScope(context);

        context.getItems().stream()
                .flatMap(i -> i.getScopes().stream())
                .distinct()
                .max(new ScopeComparator())
                .filter(s -> s != context.getScope())
                .ifPresent(s -> context.getWinner().getNode().setData(REDUCED_SCOPE, s));
    }

    static class ScopeComparator implements Comparator<String> {
        List<String> orderedScopes = Arrays.asList("compile", "runtime", "provided", "test");

        @Override
        public int compare(String lhs, String rhs) {
            return orderedScopes.indexOf(rhs) - orderedScopes.indexOf(lhs);
        }
    }
}