maven-model-builder/src/test/java/org/apache/maven/model/building/FileToRawModelMergerTest.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.model.building;

import java.lang.reflect.Method;
import java.lang.reflect.ParameterizedType;
import java.lang.reflect.Type;
import java.util.List;
import java.util.stream.Collectors;
import java.util.stream.Stream;

import org.apache.maven.model.v4.MavenMerger;
import org.junit.jupiter.api.Test;

import static org.hamcrest.MatcherAssert.assertThat;
import static org.hamcrest.Matchers.hasItems;

class FileToRawModelMergerTest {

    /**
     * Ensures that all list-merge methods are overridden
     */
    @Test
    void testOverriddenMergeMethods() {
        List<String> methodNames = Stream.of(MavenMerger.class.getDeclaredMethods())
                .filter(m -> m.getName().startsWith("merge"))
                .filter(m -> {
                    String baseName = m.getName().substring(5 /* merge */);
                    String entity = baseName.substring(baseName.indexOf('_') + 1);
                    try {
                        Type returnType = m.getParameterTypes()[0]
                                .getMethod("get" + entity)
                                .getGenericReturnType();
                        if (returnType instanceof ParameterizedType) {
                            return !((ParameterizedType) returnType).getActualTypeArguments()[0].equals(String.class);
                        } else {
                            return false;
                        }
                    } catch (ReflectiveOperationException | SecurityException e) {
                        return false;
                    }
                })
                .map(Method::getName)
                .collect(Collectors.toList());

        List<String> overriddenMethods = Stream.of(FileToRawModelMerger.class.getDeclaredMethods())
                .map(Method::getName)
                .filter(m -> m.startsWith("merge"))
                .collect(Collectors.toList());

        assertThat(overriddenMethods, hasItems(methodNames.toArray(new String[0])));
    }
}